ALBERT

Notes: Ring-opening copolymerization studies were made on the systems cyclopentene (CPE)/ norbornene (NBE), cyclooctene (COE)/ norbornene, 1,5-cyclooctadiene (COD)/norbornene, cyclopentene/cycloheptene (CHP), and cyclopentene/ 1,5-cyclooctadiene using olefin metathesis catalysts.13C NMR spectra of the copolymers permit direct determination of the reactivity ratios in most cases, as well as the proportion of cis double bonds in each type of dyad. For CPE/NBE, COD/NBE and CPE/CHP the reactivity ratios vary widely with the catalyst system and sometimes with the catalyst/cocatalyst ratio and method of mixing. There is no correlation between composition of the copolymer and cis content. The copolymers show either a random or blocky distribution of monomeric units. The results are discussed in terms of a mechanism in which the metal carbenes formed in the propagation processes are initially coordinated to the polymer chain and can add further monomeric units stereospecifically while in this form. These propagation processes compete with a relaxation process leading to a metal carbene in which the polymer chain is no longer coordinated at the vacant site and which adds monomer in a less stereospecific fashion.

Notes: With the aid of D-glyceric acid as a template, an amino- and a boronic acid group, respectively, were introduced in a defined steric arrangement into polymers. For this, the monomer D-N-(4-vinylphenyl)carbamoylethylenedioxy(4-vinylphenyl)borane (1) was copolymerized into macroporous polymers under various conditions. The template D-glyceric acid was split off from the polymer with 20% HCl in methanol. The specificity of the polymers obtained with one amino- and one boronic acid group, respectively, per cavity was derived from their ability to resolve racemic glyceric acid. Racemic resolution was also observed on equilibration of the polymers with D,L-methyl glycerate and D,L-glyceraldehyde.

Notes: Sulfomethylated resins are prepared by polymer analogous reactions, starting from macroporous poly(styrene-co-divinylbenzene) matrices. Different reaction paths are discussed and used in the synthesis. Sulfomethylation can be achieved by reaction of a chloromethylated resin with dimethyl sulfide and sodium sulfonate or alternatively by oxidation of polymer-bound thiol groups. Both methods give high conversions as shown by IR spectra and titration of the sulfonic acid groups. Poly[1-(4-hydroxysulfomethylphenyl)ethylene] (3) is obtained by reaction of poly[1-(4-hydroxyphenyl)ethylene] (2) resin with formaldehyde/sodium sulfonate. The thermal stability, catalytic activity, and ion exchange equilibria of the sulfomethylated resin are investigated.

Notes: Radical copolymerizations of mono- and di-l-menthyl fumarate (1 and 2) with styrene (St) were carried out, and the copolymers were hydrolyzed with potassium hydroxide. The products show still optical activity even after the removal of the optically active side chain, because of an introduction of asymmetry into the main chain of the copolymer. The specific rotation per one of the diad sequences of hydrolyzed poly(1-co-St) was the same as that of hydrolyzed poly(2-co-St). The mechanism of asymmetric induction and the position of the new asymmetric center are discussed based on the measurements of UV spectra, optical rotation, and circular dichroism.

Notes: The synthesis of 6-vinylchrysene (1) starting from chrysene is described. The study of the polymerizability of 1 by conventional radical, cationic, and Ziegler-Natta procedures indicates the tendency of 1 of give head-to-tail polymeric products with a similar degree of polymerization independent of the catalytic system. Copolymers of 1 with optically active (-)-menthyl acrylate (2), (-)-menthyl methacrylate (3), and (S)-4-methyl-1-hexene (4), were also prepared. No apparent copolymerization of 1 with optically active alkyl vinyl ethers occurred by cationic initiation. Spectroscopic and chiroptical properties are presented to support the formation of copolymer macromolecules. Finally, the differential dichroic absorption measurements allow one to stress that in optically active vinylaromatic copolymers the extent of preferential asymmetry, induced by the dissymmetric field of units derived from the optically active nonaromatic comonomer, increases with increasing bulkiness and polarizability of the vinylaromatic comonomer.

Notes: The 13C NMR spectra of methylstyrenes and methoxystyrenes and their polymers prepared with radical initiators, a Ziegler catalyst, or a cationic catalyst were measured. The spectra of the polymers were assigned by the chemical shifts of the monomers and gated-decoupling method. The absorption of the aromatic C1 carbon of each polymer, which varied by the polymerization conditions, was assigned in terms of a pentad sequence assuming that the Bernoullian statistics holds for the polymerization of ring substituted styrenes. The stereoregularities calculated from C1 carbon absorptions were compared with those of polystyrenes obtained unter the same polymerization conditions. In the radical polymerization of ortho-derivatives, where the substituent locates near the polymer backbone, high syndiotactic polymers (Pr = 0,80 - 0,83) were prepared. The effect of the substituent in para-derivatives did not appear. On the other hand, random polymers were generally fromed by cationic polymerization regardless of the position and the type of the substituent.

Notes: The stereoregularity of the polymers of ortho-, meta-, and para-methylstyrenes prepared with various anionic catalysts was determined by means of 13C NMR spectroscopy. The substituent effect on the stereoregularity was discussed comparing with that of polystyrenes obtained under the same polymerization conditions. Syndiotactic-rich poly(methylstyrene)s were prepared with butyllithium in toluene and the syndiotacticity increased in the order of para-, meta-, and ortho-derivatives. Although the structure of the polymers prepared with sodium-naphthalene (Na-naph.) in THF did not change with the position of the substituent, in toluene, however, the methyl group at ortho-position influences the stereoregularity. The trend of the stereoregularity of the polymers produced by potassium-naphthalene was almost the same as that of poly(methylstyrene)s prepared by Na-naph. Nearly random polymers were obtained with the cesium ion as catalyst.

Notes: Polymerization of 1-(4-pyridyl)-1,3-butadiene (PyBu) initiated by 2,2′-azoisobutyronitrile (AIBN) or butyllithium (BuLi) was studied. Radical polymerization gave poly(PyBu) of low molecular weight, soluble in chloroform, tetrahydrofuran, or methanol. PyBu was polymerized by BuLi more rapidly than by AIBN, but the produced polyanion was not living. IR and 1H NMR spectra of poly(PyBu) indicate the presence of trans-1,4-and trans-3,4-units. The content of trans-1,4-units was found to be 75 mole-% (for radical polymerization) or 90 mole-% (for anionic polymerization). From radical copolymerization with styrene the following reactivity ratios resulted: r1 (PyBu) = 7,21, r2 (styrene) = 0,12; Q = 6, 1 and e = -0,42 (for PyBu). Reaction of PyBu with ethyl bromide in benzene at 30°C produced a polyelectrolyte, as observed in the case of 4-vinylpyridine.

Notes: The stereoregularity of poly(methoxystyrene)s was determined from the absorption of the aromatic C1 carbon assuming a first-order Markov statistics holds for the polymerization as well as polystyrenes. The stereoregularity of poly(p-methoxystyrene)s prepared by sodium, potassium, or rubidium cations as catalysts in THF hardly varied and syndiotactic-rich polymers were obtained, whereas a random polymer was formed with cesium-naphthalene. In the polymerization of p-methoxystyrene in toluene, syndiotactic-rich polymers were obtained with butyllithium and random polymers were prepared by sodium or potassium cations as catalysts. The stereoregularity of poly(o-methoxystyrene)s prepared by sodium or potassium cations in tetrahydrofuran changed with the polymerization temperatures, and highly syndiotactic polymers were formed at-78°C. The structure of poly(o-methoxystyrene)s obtained in toluene, markedly depended on the initiators; that is, with increasing the size of the ionic radius of the counterions, the isotacticity of the polymers decreased. The mechanism of the polymerization and the substituent effect of the stereoregularity are discussed.

Notes: α,ω-Dimethoxycarbonyl substituted polyenes were synthesized by co-metathesis between 1,5-cyclooctadiene (1) and dimethyl 3-hexenedioate (2) by use of the catalytic system WCl6/Sn(CH3)4. The ability of 2 for co-metathesis with 1 was proved by determination of the distribution of low molecular weight products in terms of reaction time and 2/1 mole ratio. For these studies, high values of 2/1 ratios (0,5-4) were chosen in order to obtain lowest molecular weight co-metathesis products (3b-3e). Metathesis involved preferentially the double bonds in the neighbourhood of the ester groups. At lower values of the 2/1 ratio (0,012-0,061) α,ω-difunctional prepolymers (3i) were synthesized.

Notes: The 1H NMR spectra of poly(methyl acrylate-d1) +CHD—CH(COOCH3)+n were measured in o-dichlorobenzene and CDCl3 in the temperature range between - 20 and 145°C. Trans and gauche coupling constant were determined from the temperature dependence of the geminal coupling constants, neglecting g' conformers. It was estimated that the proportion of trans conformer is 1,5 to 1,9 times that of the gauche conformer in this temperature range.

Notes: The intrinsic viscosities of a Gaussian chain with and without hydrodynamic interaction preaveraging and with the identification of the centre of gravity of the Gaussian coil with the chain center were calculated using Tsuda's theory. It appears that the value of the Flory constant is more affected by approximations used in the derivation of Tsuda's theory than by preaveraging of hydrodynamic interaction. Svetlov's theory was used in the calculation of the ratio of intrinsic flow birefringence to intrinsic viscosity. For unpreaveraged hydrodynamic interaction this quantity is lower by some 15-20% than for a free-draining coil.

Notes: Homopolymers of 2,3-epoxypropyl methacrylate with various molecular masses were prepared by solution polymerization with 2,2′-azoisobutyronitrile as initiator. The effect of polymerization conditions on the molecular parameters (weight- and number-average molecular masses MW and Mn intrinsic viscosity [η]) and the tacticity of the resulting poly (2,3-epoxypropyl methacrylate)s was investigated. For unfractionated polymers, the constants of the Mark-Houwink equation for 1,4-dioxane and tetrahydrofuran were determined. Gel permeation chromatography was tested as a tool for the determination of the Mw and Mn values.

Notes: The presence of the α-methyl group in the alternating methyl methacrylate-styrene copolymer produces a remarkable difference in its 13C NMR spectra as compared with the spectra of the alternating methyl acrylate-styrene copolymer; cotacticity-dependent splittings occur only in the former spectrum. A theoretical interpretation was attempted for this characteristic spectral variation in terms of the calculated time-averaged chemical shifts for carbons in the dyads constituting the alternating copolymers. Each (meso or racemic) dyad sequence is considered to exist in several conformational states which are mutually exchanging rapidly and the probabilities of which are determined by a statistical mechanical procedure. The calculation of cotacticity-dependent chemical shifts is conducted for the side chain carbonyl, aromatic C1 and methoxyl carbons as well as for some main chain carbons to give good agreement with the observed peak splittings, especially with respect to the side chain carbons. In accordance with the reported assignment, the calculated differences in shielding factors between meso and racemic dyads for the side chain carbons of poly(methyl methacrylate-alt-styrene) are positive, i.e. the meso or isotactic peak appears at higher field than the racemic or syndiotactic peak. Furthermore, the resulting values are relatively large (≈0,63 ppm) in conformity with the experiment. The calculation for the carbons in poly(methyl acrylate-alt-styrene) gives a very small shielding difference (-0,04 to 0,06 ppm) by the dyad cotacticity, being consistent with the observation, i. e. absence of peak splittings.

Notes: Tacticity-dependent splittings observed in 1H and 13C NMR spectra of poly(methyl methacrylate) are elucidated by a theoretical procedure which consists of conformational analysis of the polymer chain and shielding calculation. The conformation is analyzed by the statistical mechanical method combined with the force field energy calculation on the dyad sequence models. As significant shielding factors, diamagnetic, anisotropic, and electrostatic terms are taken into account for the chemical shifts of 1H NMR, while paramagnetic, diamagnetic, and anistropic terms are considered for 13C NMR. The calculation is used to assing the α-methyl proton, methoxyl proton, methylene proton, quaternary carbon, methylene carbon, α-methyl carbon, carbonyl carbon, and methoxyl carbon peaks split due to dyad and triad cotacticities. The results are generally consistent with the observed spectra. Especially, the calculated splitting widths are in quantitative agreement with the observed splittings of the methoxyl and α-methyl protons resonances as well as of the carbonyl and α-methyl carbons resonances. Effects of temperature and stereoregularity on the spectra are also discussed.

Notes: The crystal unit cell of a series of normal diamides, R—NHCO—(CH2)2n—CONH—R (1) with R=CH3—(CH2)5— and n varying from 0 up to 4, has been determined from X-ray diffraction patterns of oriented films. This work forms part of the study to investigate the relation between microstructure and physical properties, in particular diamagnetism. The unit cell is tricline for all members of the series having one chain molecule per unit cell. The structure of normal diamides consists of extended chains tilted 75° from the sheet edge allowing hydrogen-bond formation within the sheet. The long spacings obtained have been associated to oblique structures of hydrogen-bonded sheets, except for the diamide with n = 1. A. shear between adjacent hydrogen-bonded sheets of 3 repeating chain units offers the most probable explanation for the structure of 1 with n = 0,2,3 and 4.

Notes: Heteroaggregations of the pair of cyanine dyes pinacyanol and thiacarbocyanine induced by the polyanions poly(potassium styrenesulfonate) and poly(potassium vinyl sulfate), and of methylene blue and acridine orange induced by mercuric chloride are described. In each case the characteristic of heteroaggregation, namely the enhancement of the metachromatic band of the partner dye having λmax at relatively shorter wavelength at the expense of the absorbance at the metachromatic band of the other dye, is reflected in the difference spectra. The dependence of the shape of the metachromatic band of pinacyanol on the nature of the polyanion inducing metachromasia is also reflected in the heteroaggregation of this dye and thiacarbocyanine induced by the two different polyanions. Mercuric chloride, though not a polyanion, also induces strong heteroaggregation of methylene blue and acridine orange.

Notes: The extrapolated melting point of native 1,4-trans-isotactic-polypentadiene obtained by inclusion polymerization in pre-irradiated perhydrotriphenylene is 104°C, 10 K higher than that of a long-annealed conventional polymer. The WAXS spectrum corresponds to that of the already known paracrystalline structure; this notwithstanding, its heat of melting is 20-70% higher than that of polypentadiene crystallized from solution or from the melt. The native polymer shows noteworthy superheating phenomena and is not able to induce crystallization of high-melting crystals from the melt. This behaviour is consistent with that predicted for extended-chain polymeric crystals. This conclusion is supported by the absence of definite peaks in the SAXS spectrum of the native polymer.

Notes: Semi-interpenetrating polymer networks based on polystyrene and polystyrene-polyisoprene three-block copolymers (SIS) were prepared by anionic polymerization. Factors affecting synthesis, such as composition, molecular weight of either the unattached SIS or the polystyrene between crosslinks, elastomer content, have been varied. Their effect on network formation was examined by extraction experiments and swelling measurements. Their morphology was investigated by means of electron microscopy.

Notes: 2-(2-Hydroxy-5-vinylphenyl)-2H-benzotriazole (9) was prepared by a seven step synthesis in about a 25% overall yield starting from o-nitroaniline. Diazotization in aqueous HCl gave a diazonium salt which was coupled with p-ethylphenol to an azo-dye which was reduced with zinc powder in sodium hydroxide solution to 2-(2-hydroxy-5-ethylphenyl)-2H-benzotriazole (4). This compound was acetylated and then brominated with N-bromosuccinimide to 2-[2-acetoxy-5-(1-bromoethyl)phenyl]-2H-benzotriazole (6) which was dehydrobrominated with triethylamine in acetonitrile or tributylamine in dimethylacetamide to the vinyl compound which was hydrolyzed to 9. This monomer was readily homopolymerized and copolymerized with styrene and methyl methacrylate using 2,2′-azobis(2-methylpropionitrile) as initiator.

Notes: The photodecomposition of α-methoxydeoxybenzoin (1) and α,α-dimethoxydeoxybenzoin (2) was investigated both in the absence and in the presence of 1,1-diphenylethylene. The resulting products indicate that benzoyl radicals add to the olefinic double bond (initiation of polymerization), whereas the α-methoxybenzyl radicals generated from 1 do not add to the olefinic double bond (no initiation), but preferentially combine with other radicals (termination of polymerization). This reaction is largely suppressed in the case of α,α-dimethoxybenzyl radicals generated from 2 owing to sequential fragmentation into inactive methylbenzoate and highly reactive methyl radicals which add to the olefinic double bond and thus contribute to the initiation.

Notes: New poly[(amino)amide]s (4) deriving from 1,2,4,5-benzenetetraamine and terephthalic, isophathalic, or 2,5-furandicarboxylic acid (2a-c) were indirectly prepared by detosylation of the corresponding new poly[(tosylamino)amide]s 3, which were obtained by low-temperature solution polymerization of 4,6-ditosylamino-1, 3-phenylenediamine (1) with the dicarboxylic acid dichlorides 2a-c. In a subsequent step the poly[(amino)amide]s were converted by polydehydrocyclocondensation into the heat-resistant aromatic poly(imidazo[4,5-f]benzimidazole)s (5) by heating in a high vacuum. The results of elemental analysis, IR and UV spectroscopy, inherent viscosity measurements, molecular weight determination (osmometry), and thermal analysis (DSC, TG) of the prepared polymers are compared and discussed.

Notes: Butadiene polymerization with hydrogen peroxide resulted in the simultaneous formation of oligomers, polymers, and high polymers. Analyses of their microstructures showed that oligomers have a higher content of 1,2-structures (28%) than the polymers (22%). The nature of the chain ends was determined with low molecular weight compounds. The content of 1,2-units is distinctly higher in the oligomers, which shows that initiation takes place preferably in 1,2- and propagation in 1,4-position. Besides hydroxyl end groups, other functional groups were detected in small quantities in the low molecular weight products: aldehydes, ketones, acids, hydroperoxides, and epoxides. These functions result from secondary reactions such as transfer, initiation, or termination reactions with alcohol releasing radicals.

Notes: The addition of hydroxyl groups on double bonds during the synthesis of unsaturated polyesters is studied with the help of model molecules. These are diesters of unsaturated diacids (maleic and fumaric acids) or monoesters of unsaturated monoacids (crotonic, cinnamic and p-cyanocinnamic acids) with 1,2-propanediol. The addition reaction take place to appreciable extents only with bis(hydroxypropyl) maleate and fumarate. The reaction is catalyzed by strong acids such as p-toluenesulfonic acid; it is reversible and favoured by high temperatures. A mechanism is discussed.

Notes: By means of a Wittig condensation polymerization starting from 4,4′-azodibenzaldehyde (1) and bifunctional Wittig salts of the benzene and thiophene series (2a-c) poly(azo-1, 4-pheny-leneivnylenearylene)s (3a-c) were synthesized. Analogously the model compounds 6a-c, 8a-d, and 10a-c were prepared. The structures of the intensive red to brown polymers and the orange to red model compounds were proved by elemental analyses, IR- and electronic spectra, respectively mass spectral data for the model compounds. The thermooxidative degradation of the polymers and the electrical conductivity of the polymers and model compounds were studied.

Notes: Condensation of 4-aminoazobenzene (1), respectively 4, 4′-diaminoazobenzene (2), with mono- and dialdehydes of the benzene and thiophene series yields intensive coloured polymeric azomethines (polymeric Schiff bases) with azobenzene units, respectively model compounds. The structure of these polymers and model compounds were confirmed by elemental analyses, IR-and electronic spectra and  -  in the case of the model compounds  -  by MS and 1H NMR spectra. The electrical conductivities of the polymers and model compounds and the thermo oxidative degradations of the polymers were studied.

Notes: A few unsaturated polysters prepared by melt polycondensation of maleic anhydride, phthalic anhydride, and aliphatic glycols in different proportions have been characterized. The salient features of the 1H and 13C NMR spectra of the polyesters and of model compounds are compared. It appears that from 15 to 20% of maleic acid residues have reacted with excess glycol to yield branching points while the remaining free olefinic double bonds have undergone cis → trans isomerization almost quantitatively along the oligomeric chains.

Notes: The reaction of 6,6-dimethylfulvene (1) with small amounts of sodium cyclopentadienide (Na-CPD) gives a mixture of oligomeric products, from which 1-cyclopentadienyl-1,3,3,-trimethyltetrahydropentalene (7) was isolated with 67% yield. The structure of the main product 7 was proved by combination of spectrosopic methods as well as by NMR spectroscopy of its dianion. A reasonable reaction mechanism is presented and supported by isolation of other dimers 9 and 12 and trimers 10 as well as of side products 11 and 13. The product distribution is severely influenced by increasing the amount of Na-CPD (favouring oligomers of type 11 and 13) as well as by addition of crown ether.

Notes: Solution properties of poly(A) and poly(I) solution at a mole ratio of poly(A) to poly(I) of 1/2 were studied by means of calorimetry and a modified differential scanning calorimetry (DSC) with the help of circular dichroism (CD) and ultraviolet (UV) spectral methods. It was found that the heat of mixing, ΔHM, depends sharply on the ionic strength. At [NaCl] 〈 10-2 mol · dm-3 ΔHM is nearly zero. At higher ionic strength ΔHM decreases and reaches a minimum value at [NaCl] ≍ 2 · 10-2 mol - dm-3. Above this ionic strength ΔHM increases again. This behavior is explained on the basis of the formation of a triplex poly(A) · poly(2I) and the transition of poly(I) from a disordered to an ordered structure with increasing ionic strength. The heat of formation, ΔH, of the poly(A) · poly(21) triplex was estimated to be ca -41 kJ per mole of base triplet. Above an NaCl concentration of 2 · 10-1 mol · dm-3 the triplex formation may be represented by the following scheme: \documentclass{article}\pagestyle{empty}\begin{document} $$\begin{array}{*{20}c} {{\rm Poly}({\rm A}) + 2{\rm poly}({\rm I})\ ({\rm order})} \hfill \\ {{2\Delta {\rm H}_{\rm t}\atop{-\hskip-1.5pt-\hskip-1.5pt\longrightarrow}} \quad {\rm poly}({\rm A}) + 2{\rm poly}({\rm I})\ ({\rm disorder})} \hfill \\ {{\Delta {\rm H}\atop{-\hskip-1.5pt-\hskip-1.5pt\longrightarrow}} \quad {\rm poly}({\rm A}) \cdot {\rm poly}(2{\rm I}){\rm\ triplex}} \hfill \\ \end{array}$$\end{document}

Notes: Micelles of a block copoymer poly(styrene/butadiene/styrene) with cores consisting of polybutadiene blocks were stabilized in dilute solutions by UV radiation in the presence of a photo-initiator and also by fast electrons, and micelles of a block copolymer poly(styrene/ethene-co-1-butene/styrene) with cores formed by the aliphatic blocks were stabilized by fast electrons, in dilute solutions. Stabilization of micelles, i. e., crosslinking of the chains in micellar cores as well as the properties of stabilized micelles were studied by conventional light scattering, by light scattering photon correlation spectroscopy and by gel permeation chromatography.

Notes: The polymorphic behaviour of polymers \documentclass{article}\pagestyle{empty}\begin{document}$% MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabeikayaaqa % Gaae4taiaab+eacaqGdbGaeyOeI0IaaeikaiaaboeacaqGibWaaSba % aSqaaiaabkdaaeqaaOGaaeykamaaBaaaleaacaqGUbGaaeylaiaabk % daaeqaaOGaeyOeI0Iaae4qaiaab+eacaqGpbGaeyOeI0Iaae4qamaa % BaaaleaacaqG2aaabeaakiaabIeadaWgaaWcbaGaaeinaaqabaGccq % GHsislcaqGdbGaaeikaiaaboeacaqGibWaaSbaaSqaaiaabodaaeqa % aOGaaeykaiaab2dacaqGdbGaaeisaiabgkHiTiaaboeadaWgaaWcba % GaaeOnaaqabaGccaqGibWaaSbaaSqaaiaabsdaaeqaaOGabeykayaa % qaWaaSbaaSqaaiaabIfaaeqaaaaa!560E! {\rm \rlap{--} (OOC} - {\rm (CH}_{\rm 2} {\rm )}_{{\rm n - 2}} - {\rm COO} - {\rm C}_{\rm 6} {\rm H}_{\rm 4} - {\rm C(CH}_{\rm 3} {\rm ) = CH} - {\rm C}_{\rm 6} {\rm H}_{\rm 4} {\rm \rlap{--} )}_{\rm X} $\end{document}(n = 8, 10) has been investigated. They show thermotropic, mesophasic properties with a nematic structure. Both polymers exhibit a multiple solid state polymorphism which is a function of the temperature and of their thermal history.

Notes: As a part of studies on wholly aromatic polyamides containing bridged biphenylylene groups, poly(3,8-phenanthridinonediyl terephthalamide) (DAP-T) was prepared from 3,8-diaminophenanthridinone and terephthaloyl chloride. The solutions of DAP-T samples in high concentration sulfuric acid exhibited optically different phases, depending on temperature and concentration, like those of poly(1,4-phenylene terephthalamide) (PPD-T). The phase diagram of the DAP-T-99,0% H2SO4 system was established and compared with that of the PPD-T-99,0% H2SO4 system. Both were essentially similar. The flow of high concentration dopes of DAP-T and PPD-T through spinneret holes showed non-Newtonian characteristics. The liquid-crystalline solutions of DAP-T in 99,0% sulfuric acid were spun into fibers using water as a coagulant. The tensile strength and initial modulus increased with increasing degree of stretching between spinneret and collection roller. The annealing of fibers caused an increase in tenacity and modulus, and a tensile strength of 25 g/den and an initial modulus of 1 000 g/den could be reached. Both spun fibers and annealed fibers showed x-ray diffraction patterns displaying distinct layer line streaks, from which the fiber period was estimated to be 17,2 Å. This agreed with the repeat distance in the direction of molecular axis calculated on the basis of extended chains with trans-conformation.

Notes: A new method for the determination of the cmc using a dialysis technique which allows monomeric species to diffuse through but not micelles has been applied for determining the mixed micelle composition. The method is based on determining the amount of surfactant that diffuses through at two different times which allows for the calculation of the cmc by use of the appropriate equation. This method requires the preparation of only one concentration of solution and lends itself particularly well to the determination of the composition of mixed micelles.

Notes: A number of wholly aromatic copolyamides containing bridged biphenylylene groups were synthesized from a mixture of aromatic diamines and terephthaloyl chloride, on one hand, and from a mixture of aromatic diacid dichlorides and 1,4-phenylenediamine, on the other hand. Each mixture of diamines and of diacid dichlorides was constituted of a phenylene derivative and a bridged biphenylylene derivative. The copolyamides synthesized were dissolved in high concentration sulfuric acid and spun into fibers. The fibers spun showed fairly high tensile strengths and high initial moduli, but annealing caused further increase in strength and modulus. All the copolyamides studied had very high thermal resistances.

Notes: Practical hints for the application of the indirect Fourier transformation method are given. In detail there are discussed the problems of stabilization of the least squares routine, the estimation of the maximum dimension of the particles, the choice of an appropriate number of the spline functions, the combination of scattering functions measured with different primary beam geometry, standard deviation and error propagation of the solution functions, influence of the interparticle interference effect and background scattering on the results, determination of the radius of gyration and the scattering intensity at zero angle and finally the possibility of simulation of measuring curves starting with model bodies is described. It is attempted to demonstrate the advantages of indirect Fourier transformation on hand of several practical examples.

Notes: Systematic studies were performed on interpolymer complex formation between Poly(acrylic acid) (PAA) and poly(ethylene oxide) (PEO) in THF-water mixtures of different compositions. Viscosity behaviour during complex formation in mixed solvents was found to be entirely different from that observed by other workers in aqueous and in pure organic solvents. The result are interpreted in terms of, (a) preferential solvation of the polymer, (b) Probable change in conformation of the polyelectrolyte moleculer. (c) association of complex molecules in a medium of low dielectric constant, and (d) expected disordering of bound water molecules around PEO by THF. Irrespective of solvent composition, interpolymer complex of PAA and PEO was always found to have 1:1 unit mole ratio.

Notes: Non-Newtonian viscosity could be explained by the Graessely entanglement viscosity theory modified by a frictional viscosity for moderately concentrated solutions of polydimethyIsiloxanes over a range of shear rates from lower to upper-Newtonian flow. The expansion of a polymer molecule was kept under control by use of solvents with different dissolving powers of the polymer. The result shows that only the frictional viscosity is strongly related to the degree of expansion of a polymer molecule in solution and that Graessley's plots are independent of that. Extrapolation of the frictional viscosity versus concentration curves to 100wt.-% show a common value of 0,09 Pa·s in spite of different degrees of expansion of the polymer molecules in solution. This common value was equal to the viscosity value for melt polymer with the same molecular weight as a polymer segment. It is concluded that the frictional viscosity is caused by solvent-solvent, solvent-polymer segment, and segment-segment interactions.

Notes: A modified method for the determination of the number of isotactic sites C* and the overall propagation rate constant k̄p of propene polymerization catalysts with 14C-labelled carbon oxides is proposed: an excess of 14CO2 or 14CO is added in the abscence of propene and alkylaluminium to a non-deactivated polymer sample drawn from the polymerization slurry.The specific radioactivity of the polymer as a function of the time of contact with the radio-actively labelled inhibitor sharply increases within short times of contact (14CO2 ≤ 20 min, 14CO ≤ 5 min). This is followed by a slower further increase reaching a finite value after 5 to 7h. The initial and end values differ by a factor of 2 to 3. The results are explained in terms of sites with different reactivity assuming that the total number of isotactic sites is determined only after long times of contact with the inhibitor.So far c* was determined with 14CO2 or 14CO by adding the inhibitor during the polymerization in the presence of propene and alkylaluminium; c* was calculated after short times of contact with the inhibitor, whereas the further steady increase in specific radioactivity was exclusively attributed to side reactions caused by reaction with propene and alkylaluminium.By this modified method we obtained for TiCl3·(1/3)AlCl3 at 60°C k̄p = 13 dm3/(mol·s) and c* = 0,012 mol Ti*/mol Titotal. Addition of a free Lewis base to the polymerization mixture increases c* leaving k̄p unchanged. In contrast to this, if TiCl3·(1/3) AlCl3 is milled with a Lewis base k̄p can be increased by a factor of ≈ 2,5 with lower or equal c* -values. The higher activity of extracted TiCl3-catalyst is due to higher k̄p and c* -values as compared to those using TiCl3·(1/3) AlCl3.

Notes: Coordination polymers, \documentclass{article}\pagestyle{empty}\begin{document}$% MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabeikayaaqa % GaaeytaiaabshacaqGmbGabeykayaaqaWaaSbaaSqaaiaab6gaaeqa % aaaa!3B21! {\rm \rlap{--} (MtL\rlap{--} )}_{\rm n} $\end{document} were synthesized by condensation of bis(salicylaldehydo)-metal(II) (metal = Co, Ni, and Cu) with diamines (1, 4-diaminobenzene and 4,4′-diaminobiphenyl). Their composition, structure, thermal stability, and physical properties were investigated by analytical, magnetic, spectral (IR and DRS), the thermogravimetric studies. It was found that in the bis(salicylaldehydo)metal(II)-chelates, two salicylaldehyde molecules are linked to each metal ion through the oxygen atoms of the phenolic and aldehydic groups and in the polymeric complexes the nitrogen atoms of the amino groups replace the aldehyde oxygens. The diamine molecule is thus acting as a bridging unit between two salicylaldehydometal(II) units, forming structures 1 and 2. The polymers obtained from 4,4′-diaminobiphenyl (2a-c) are thermally more stable than those from 1, 4-diaminobenzene (1a-c), the order of thermal stability in both cases being Ni(II) 〉 Cu(II) 〉 Co(II). Co(II) and Cu(II)-complexes are paramagnetic, whereas Ni(II)-complexes are diamagnetic. The reflectance spectra along with the magnetic data suggest a square planar structure for Cu(II) and Ni(II)-complexes, and a tetrahedral one for the Co(II)-complexes.

Notes: The nature of alkali derivatives of acetone (ADA) and active centres (AC) in the anionic polymerization of isopropenyl methyl ket one (IMK) was studied by means of IR spectroscopy. Solutions of ADA and of the AC of IMK in tetrahydrofuran show a characteristic absorption at 1560 - 1610 cm-1, due to the stretching vibrations of the delocalized isopropenyl oxide group. Two kinds of equimolar complexes are formed between acetone and ADA, depending on the nature of the counterion (Li+, Na+, K+, Cs+). The same interaction is observed between the AC of oligo (IMK) and the carbonyl group of the last but one monomeric unit (penultimate effect).

Notes: Previous Kinetic studies of the emulsion polymerisation of the three component system acrylonitrile (A)  -  styrene (S)  -  methyl acrylate (M) have shown that S is much more reactive than A and M, which have practically the same reactivities. As a consequence, in batch process a large copolymer composition drift is observed versus conversion. To avoid this damageable drift, two techniques were investigated, to get homogeneous macromolecules. (1) Application of the well known “semi-continuous technique” which appeared not to be totally satisfactory, since the initial batch polymer fraction generally has a composition different from the further polymer when the monomer feed is added under starving conditions; a mixture of various macromolecules is the result. (2) The use of the composition controlled reactor, developed in this laboratory, which consists in a continuous monitored readjustment of monomer feed composition. However, due to the heterogeneous medium of an emulsion copolymerization, the copolymer exerts a small chemical heterogeneity which may be practically negligible at high monomer/water ratio. It is finally proposed that a thermodynamic approach might overcome such a behaviour and insure an actual control of the copolymer composition.

Notes: The interaction of Ni[P(OR)3]4 (R = C2H5 or C6H5) with chlorinated rubber (CR) of CCl4 is studied. The results of the polymerization of methyl methacrylate (MMA) initiated by the system CR or CCl4—Ni[P(OR)3]4 depend on the order in which the reagents are introduced. Trialkylphosphite, tetrakis(trialkylphosphite) nickel and the products resulting from the reaction of CCl4 or CR with Ni[P(OR)3]4 are characterized by 31P NMR. From this study, it appears that the initiation of polymerization by the system chlorinated compound-nickel derivative does not involve the formation of free phosphite, which is at variance with previously reported assumption. 1H NMR study supports these results.

Notes: The reaction of a diisocyanate and an asymmetric aliphatic-aromatic diacid containing a preformed imide group was studied in order to obtain polyamide-imides. It is shown in this paper that combined 1H and 13C NMR spectrometry will permit the quantitative evaluation of the proportions of head-tail, head-head, tail-tail additions, provided the content of urea in the polymer is low. In order to obtain unequivocal assignments and to thoroughly characterize the NMR spectra of the polymer, several model compounds resembling the polymer backbone were synthesized. A model polymer was synthesized with the same purpose, and its 1H and 13C NMR spectra fully assigned. Unexpected chemical functions in the polymer, like urea and carboxylic acid, can also be easily detected and quantified by NMR.

Notes: The polycondensation of 4,4′-methylenediphenylisocyanate and 6-(4-carboxyphthalimido)-hexanoic acid was studied under different conditions in order to establish the influence of factors such as temperature, catalyst, stoichiometric disbalance, and addition order of reactants on the molecular weight and the chemical composition of the final polyamide-imide. All these factors proved to influence the extent of possible side reactions that lead to undersirable functions, the main ones being urea functions that locate within the polymer backbone. Other side-reactions proposed to explain the formation of acylureas or biurets did not take place in appreciable extent since these functions could not be detected by NMR spectroscopy. Therefore, particular emphasis was made to prevent the formation of urea by changing the polycondensation conditions. A first attempt to clarify the regularity degree of the polymers (amounts of head to tail and head to head addition) by 1H NMR spectroscopy was also made.

Notes: The viscosity of dilute solutions of poly(ethyl methacrylate) in each of methyl acetate, ethyl acetate and isobutyl acetate was studied over the temperature range of 20-65°C. The intrinsic viscosity either remained approximately constant or slightly decreased over the temperature range because of conformational changes. The temperature ranges of conformational change were 40-50°C, 40-50°C, and 35-55°C for the polymer in methyl acetate, ethyl acetate, and isobutyl acetate, respectively. The Huggins constant was also influenced by the type of solvent and by temperature changes, especially over the temperature range in which conformational changes took place. Conformational changes of poly(ethyl methacrylate) in aliphatic organic esters as solvents are believed to be due to changes in the interaction between the polymer segments and the solvent.

Notes: Poly(pentamethylene sulfide)Structure-based name: poly(thiopentamethylene). (P5MS) [—S(CH2)5—]x was prepared by the condensation polymerization of nearly equimolar amounts of pentamethylene dibromide and the sodium salt of 1,5-pentanedithiol. Selective precipitations were used to obtain a fraction of the polymer, and dielectric constant measurements on solutions of it in benzene were used to obtain dipole moments over the range 20-60°C. Rotational isomeric state calculations based on conformational energies obtained from semiempirical potential energy functions gave results in fair agreement with experiment. Since extensive previous studies on a number of polyoxides have demonstrated the difficulty in calculating the energy of the O…CH2 interactions, the energy of the corresponding S…CH2 interactions in P5MS was adjusted to obtain better agreement between theory and experiment.

Notes: The copolymerization parameters of 2-acryloyoxybenzoic (AOB) and 2-methacryloyloxybenzoic (MOB) acids, methyl 2-methacryloyloxybenzoate (MMOB), and N-methyl-N-phenyl-2-aminoethyl methacrylate (MPAM) with styrene in benzene solution were determined and used in the calculation of the Alfrey-Price copolymerization constants e and Q for AOB, MOB, MMOB, and MPAM. Using e Q thus determined and the corresponding tabulated values for methacrylic acid (MAA), the copolymerization parameters of pairs AOB-MPAM, MOB-MPAM, MMOB-MPAM, and MAA-MPAM were calculated. They are compared with those determined by the copolymerization of these pairs in which the interaction of functional groups on comonomers plays a role.

Notes: Poly(vinyl chloride) of low molecular weight (the fraction extracted with a hexane/acetone mixture (vol.-ratio 3:2)) was substituted by hydroxyphenyl groups and then analyzed by 1H NMR spectroscopy. It was established that the 1H NMR spectra of hydroxyphenyl substituted poly(vinyl chloride) prepared by removal of HCl, allows to determine the number of unsaturated end groups and to distinguish between the structures —CHCl—CH2—CH=CH—CH2Cl and —CH2—CHCl—CH=CH—CH2Cl, and even between their trans and cis forms. In addition the 1H NMR spectra of hydroxyphenyl substituted poly(vinyl chloride) prepared without removal of HCl allow to determine the total number of unsaturated end groups.

Notes: The polymerization of 2-pyrrolidone (1) initiated with its potassium salt (2-oxo-1-pyrrolidinylpotassium) (2) and accelerated by the presence of CO2, was investigated. For the optimal concentration of 2 (≈5 mol-%) and 0,5 mol-% CO2, the most suitable polymerization temperature was found to the range between 45 and 55°C. The variation of CO2 concentration, 0,5 〈 [CO2] 〈 3 mol-%, does not affect the polymerization yield under the optimal conditions. The similarity of the course of polymerization in the presence of CO2 directly introduced into the reaction mixture with that in the presence of isolated carboxylate of 1, is considered as a proof that CO2 is transformed into the active potassium carboxylate of 1. The order of polymerization reaction with respect to initiator was found to be ≈0,8 indicating the complexity of the reaction mechanism.

Notes: The anionic polymerization of 1,3 and 1,4-diisopropenylbenzene (DIB) was found to be characterized by a rather low ceiling temperature and by rather strong differences in reactivity between the two double bonds. At low degrees of conversion the polymers formed are essentially linear and carry one pendant double bond per monomeric unit. Branching and crosslinking can occur only at higher conversion. 1,3-DIB can be copolymerized anionically with α-methylstyrene. Grafting reactions were carried out on polymer backbones with pendant unsaturated groups, using two different pathways. The occurence of coupling reaction can be avoided by a proper choice of experimental conditions.

Notes: From Witting-reactions of dithieno[3,2-b: 2′, 3′-d]thiophene-2, 6-dicarboxaldephyde (1) with “mono-and bis-Wittig-salts” of the benzene and thiophene series poly(dithieno[3,2-b: 2′,3′-d]-thiophene-2,6-diylvinylenearylenevinylene)s 3a - c and some model compounds 5a - c were obtained. Wittig-reactions of dithieno[3,2-b: 2′,3-d]thiophene-2-carboxaldehyde (6) with “mono-and bis-Wittig-salts” gave model compounds 7a - c and 8a, c. The structures of all compounds were confirmed by elements analyses, IR-and electronic spectra, those of the model compounds additionally by mass spectra, and in case of sufficient solubility by 1 H NMR spectra. The electrical conductivities of all compounds and the thermooxidactive degradation of the polymers 3a, c were investigated.

Notes: In contrast to conventional approaches to active centre determination in Ziegler-Natta polymerization, a method is proposed whereby the active catalyst rather than the polymerization system as a whole is studied. The method is based on the observation that addition of non-polymerizable olefins such as α-methylstyrene to catalyst systems promoted with Al(iBu)3 leads to displacement of isobutene from the active sites. Active site concentration are derived from quantitative determination of liberated isobutene or labelled cumene derived by quenching the treated catalyst with [O-3-H]-methanol. Values of active site concentration were found to be of the order of 0,3 mmol per mol of V and 2,6 mmol per mol of Ti for VCl3 and TiCl3. AA catalysts, respectively.

Notes: A series of polysters based on a triad aromatic ester mesogenic unit but containing different poly(alkylene oxide) flexible spacers in the main chain was prepared and its properties examined. The flexible spacers consisted of poly(alkylene oxide)s of varying lengths based on either oligomers of ethylene oxide or propylene oxide. The spacer types, lengths and distributions were found to strongly affect the mesophase and melting behaviors of the polymers. Polymers with spacers having more than 10 units were not liquid crystalline, whereas those of shorter length exhibited mesophase properties. The polymers containing spacers with two, three, or four oxyethylene units showed two mesophases, and the textures of their mesophases suggested that both smectic and nematic phases were formed.

Notes: In the reaction of methyl methacrylate (2) with methyl 2-sodioisobutrate (1) (a model of the active center in the anionic polymerization of 2) in a mole ratio of 2:1, the concentrations of all known initial compounds and reaction products were estimated. This reaction was studied in a flow reactor with reaction times between 0,02 and 1,4 s using GLC, LC and GPC as analytical methods. At the same time, a rise in temperature of the reaction mixture by 6°C was observed (for [2] = 0,2 mol/1); at a higher concentration of 2 (0,6 mol/1), this rise was 27°C and hence not negligible in the interpretation of the results. The concentration changes of the individual products were in accordance with the concept of a stepwise addition of 2, to the metalloesters. At the end of the reaction the mean molecular weight of the addition products corresponded roughly to the ratio 2/effective 1. The cyclization of Na-trimer 4a to a cyclic trimer 9 was shown to be an important side reaction. The Na-tetramer 5a and the higher Na-oligomers 6a probably undergo a similar cyclization. 2 added 1 very quickly; the following approximate order of reaction rates (Scheme 1) is proposed: R1 〉 R2, R3, R4, … 〉 Rc.

Notes: Linear poly(iminoethylene) was synthetised by cationic polymerization of 2-methyl-2-oxazoline using BF3—O(C2H5)2, SnCl4, and CH3COBF4 as initiators and in the presence or absence of CH3CN. The resulting product, poly(N-acetyliminoethylene), was then hydrolysed in basic medium. The resulting poly(iminoethylene) was identified and characterized by 1H NMR, 13C NMR, X-ray diffraction, and differential scanning calorimetry (DSC). The synthetised polymer will be used as a polymeric support in ionic-exchange resins as well as in macromolecular pesticides.

Notes: A new polyesterimide containg CC-double bonds was prepared by reacting an unsaturated diacid chloride containing a cyclic imido group with ethylene glycol at low temperature. The solubility, thermal, electrical and cross-linking properties of the polymer were studied. The polymer was found to be thermostable and soluble in highly polar solvents. X-ray diffraction data revealed that the polymer is crystalline. The unsaturation sites of the polymer chain could be exploited for crosslinking reactions. The swelling behavior of the crosslinked polymer was studied as well as the thermal and electrical properties. The overall thermal stability of the crosslinked polymer was found to be higher than that of the uncrosslinked polymer.

Notes: It was found that three polyconjugated polymers with anthrancene repeating units slow down the thermal and thermooxidative degradation of polystyrene. This effect is explained by charge transfer complex formation between the radicals formed during the degradation of polystyrene and the polyconjugated polymers as donors.

Notes: Preparation and characterization (by IR and 1H NMR spectroscopy) of isomeric methacrylic acid and acrylic acid derivatives of the herbicide 3-amino-1,2,4-traizole are described. Their radical polymerization and copolymerization with styrene or methyl methacrylate give polymers containing the herbicide moiety as pendant groups bound via acyl groups at the amino group or at the ring nitrogen. The reactivity ratios were determined for the isomeric methacrylic compounds.

Notes: Monofunctional telomers of vinyl chloride (1) were synthesized by two ways. In the first one, the telomers resulting from the reaction of 1 with carbon tetrachloride were used as telogenic agents to react with allyl acetate leading to a monoadduct. In the second one, monofunctional telogens were used in a redox catalyzed reaction with 1. Trichloroacetic acid and its esters (2b-d) were applied as telogens. The theoretical maximum yields and the number average degrees of polymerization at these yields were calculated and compared with the experimental results.

Notes: The nature of interactions between polyethylene and a non-wetting solute was analyzed to know if the interface can be characterized by the expression of the energy of wetting or if phenomena other than adhesion and wetting must be taken into account. In this way, the isotherms of sorption, the molar heats of interaction, the kinetic behaviour of the sorption, the permeation, and the changes of length during liquid immersion gave informations on the existence of a limited diffusion into the polymer. Two types of systems were investigated: polyethylene/water and polyethylene/methylene iodide. The formation of aggregates is discussed.

Notes: The kinetics of the thermal dehydrochlorination of PVC was investigated with respect to the initiation mechanism of the hydrogen chloride chain elimination. The constant rate of dehydrochlorination in the early stages of the dehydrochlorination process is explained by an intra-chain initiation mechanism which is a consequence of a constant amount of active sites (structural irregularities) incorporated in the chains. After an initial period, dehydrochlorination is occurring in a random way, and (or) by an inter-chain dehydrochlorination mechanism initiated by a “sudden polarization” effect between the postulated zwitterion and a meanwhile unreacted —CH2CHCl— group.

Notes: Semiflexible mesophasic polymers of the general formula \documentclass{article}\pagestyle{empty}\begin{document}$ % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabi4wayaaqa % Gaae4taiaab+eacaqGdbGaaeikaiaaboeacaqGibWaaSbaaSqaaiaa % bkdaaeqaaOGaaeykamaaBaaaleaacaWGUbGaeyOeI0IaaGOmaaqaba % GccqGHsislcaqGdbGaae4taiaab+eacqGHsislcaqGsbWaaWbaaSqa % beaacaaIXaaaaOGabiyxayaaqaWaaSbaaSqaaiaabIfaaeqaaOGaai % ilaiaad6gacqGH9aqpcaaI5aGaaiilaiaaigdacaaIXaGaaiilaiaa % igdacaaIZaGaaiilaiqacUfagaaeaiaab+eacaqGpbGaae4qaiaabI % cacaqGdbGaaeisamaaBaaaleaacaqGYaaabeaakiaacMcadaWgaaWc % baGaamOBaiabgkHiTiaaikdaaeqaaOGaaiylaiaaboeacaqGpbGaae % 4taiabgkHiTiaabkfadaahaaWcbeqaaiaaikdaaaGcceGGDbGbaaba % daWgaaWcbaGaaeiwaaqabaGccaGGSaGaamOBaiabg2da9iaaiMdaca % GGSaGaaGymaiaaigdacaGGSaGaaGymaiaaiodacaGGSaGaaGymaiaa % isdacaGGSaaaaa!6CDE! \rlap{--} [{\rm OOC(CH}_{\rm 2} {\rm )}_{n - 2} - {\rm COO} - {\rm R}^1 \rlap{--} ]_{\rm X} ,n = 9,11,13,\rlap{--} [{\rm OOC(CH}_{\rm 2} )_{n - 2} - {\rm COO} - {\rm R}^2 \rlap{--} ]_{\rm X} ,n = 9,11,13,14, $\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$ % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGabi4wayaaqa % Gaae4taiaab+eacaqGdbGaae4taiabgkHiTiaabIcacaqGdbGaaeis % amaaBaaaleaacaqGYaaabeaakiaabMcadaWgaaWcbaGaamOBaiabgk % HiTiaaisdaaeqaaOGaeyOeI0Iaae4taiaaboeacaqGpbGaae4taiab % gkHiTiaabkfadaahaaWcbeqaaiaaikdaaaGcceGGDbGbaabadaWgaa % WcbaGaaeiwaaqabaGccaGGSaGaamOBaiabg2da9iaaiMdacaGGSaGa % aGymaiaaigdacaGGSaGaaGymaiaaiodacaGGSaaaaa!5300! \rlap{--} [{\rm OOCO} - {\rm (CH}_{\rm 2} {\rm )}_{n - 4} - {\rm OCOO} - {\rm R}^2 \rlap{--} ]_{\rm X} ,n = 9,11,13, $\end{document} where \documentclass{article}\pagestyle{empty}\begin{document}$ % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeOuamaaCa % aaleqabaGaaeymaaaakiabg2da9iabgkHiTiaaboeadaWgaaWcbaGa % aeOnaaqabaGccaqGibWaaSbaaSqaaiaabwdaaeqaaOGaeyOeI0Iaae % 4qaiaacIcacaqGdbGaaeisamaaBaaaleaacaaIZaaabeaakiaacMca % cqGH9aqpcaqGdbGaaeisaiabgkHiTiaaboeadaWgaaWcbaGaaGOnaa % qabaGccaqGibWaaSbaaSqaaiaaiwdaaeqaaOGaeyOeI0caaa!4A87! {\rm R}^{\rm 1} = - {\rm C}_{\rm 6} {\rm H}_{\rm 5} - {\rm C}({\rm CH}_3 ) = {\rm CH} - {\rm C}_6 {\rm H}_5 - $\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$ % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeOuamaaCa % aaleqabaGaaeOmaaaakiabg2da9iaaboeadaWgaaWcbaGaaeOnaaqa % baGccaqGibWaaSbaaSqaaiaabwdaaeqaaOGaeyOeI0Iaae4qaiaacI % cacaqGdbGaaeisamaaBaaaleaacaaIZaaabeaakiaacMcacqGH9aqp % caqGobGaeyOeI0IaaeOtaiabg2da9iaacIcacaqGdbGaaeisamaaBa % aaleaacaaIZaaabeaakiaacMcacaqGdbGaeyOeI0Iaae4qamaaBaaa % leaacaaI2aaabeaakiaabIeadaWgaaWcbaGaaGynaaqabaGccqGHsi % slaaa!5042! {\rm R}^{\rm 2} = {\rm C}_{\rm 6} {\rm H}_{\rm 5} - {\rm C}({\rm CH}_3 ) = {\rm N} - {\rm N} = ({\rm CH}_3 ){\rm C} - {\rm C}_6 {\rm H}_5 - $\end{document} are prepared and their solid and liquid crystalline behaviour examined and compared to that of the corresponding homologues with n even. Evidence is given of relevant odd-even effects in the thermodynamic parameters of the clearing transition. The conclusion is drawn in favour of an anisotropic structuration also of the flexible parts of the polymer chain in the liquid crystal phase.

Notes: The thermal expansion coefficient of poly(oxy-2,6-dimethoxy-1,4-phenylene), PPOO, was measured from 150 to 500 K, using a thermomechanical analyzer connected to a computer for the data handling. Poly(oxy-2,6-dimethyl-1,4-phenylene), PPO, and some brominated poly(oxy-2,6-disubstituted-1,4-phenylene)s were studied as reference materials. The apparent glass transition temperatures of the high molar mass polymers were 456 K for PPOO and 487 K for PPO, and the changes in cubic thermal expansion coefficients at Tg were 6,01 · 10-4 K-1 for PPOO and 4,23 · 10-4 K-1 for PPO. The activation of the β-relaxation was found for PPOO at 260 K and attributed to the hindered torsional oscillations of the backbone phenylene groups. Another transition was found at 160 - 170 K and interpreted as the γ-relaxation due to the oscillatory motion of the methoxy groups. Reasons for the differences in the thermal expansion behaviour of PPOO and PPO are discussed.

Notes: The activation enthalpies for the structural relaxation of poly(oxy-2,6-dimethoxy-1,4-phenylene) and poly(oxy-2,6-dimethyl-1,4-phenylene) were determined by studying the dependence of the limiting fictive temperature on the cooling rate, using a differential scanning calorimeter (DSC) interfaced to a computer. The molar mass dependence of the activation enthalpies complied with the empirical equation, ΔH· = ΔH∞· - A/Mva, where ΔH∞· is the activation enthalpy of an infinite chain length polymer, Mv is the viscosity-average molar mass, a = 0,64, and A is a constant that depends on the free volume of the chain ends of the polymers. The values of ΔH∞· are 433 kJ/mol for poly(oxy-2,6-dimethoxy-1,4-phenylene) and 449 kJ/mol for poly(oxy-2,6-dimethyl-1,4-phenylene).

Notes: Relations between molar mass M and molar mass dependent properties E of polymers are mostly strictly valid only for monomolecular samples i: \documentclass{article}\pagestyle{empty}\begin{document}$ M_i = {\rm f (}E_i )\quad \quad \quad \quad \quad \quad (1{\rm a}) $\end{document} For polymolecular polymer samples the corresponding averages Mav and Eav must be applied: \documentclass{article}\pagestyle{empty}\begin{document}$ M_{{\rm av}} = {\rm f (}E_{{\rm av}} )\quad \quad \quad \quad \quad \quad (1{\rm b}) $\end{document} Provided the kind of average (number-, weight- or any general average) of e.g. Mav is known, the corresponding average Eav is given by. Eqs. (1a, b). This is demonstrated for the relationships of van't Hoff and Mark-Houwink, frequently used for the determination of molar masses of polymers. It is also shown that the four different relations for the expansion factor α by Flory-Stockmayer, Fixman, Ptitsyn, and by Yamakawa-Tanaka can be applied to polymolecular polymer samples (i.e. without fractionation), provided the corresponding averages[η]av and Mav from the Mark-Houwink relationship are taken for the evaluation of the parameters KΘ and B′.

Notes: Polymerization of ethylene oxide (EO)-catalyzed by a binary system consisting of triphenyl-antimony dibromide (TPAB) and triphenylphosphine (TPP) was carried out. TPAB itself could induce the polymerization, but the addition of TPP to TPAB greatly enhances the catalytic activity. A characteristic inflection point, which appeared clearly in the time-polymerization curves, divided the polymerization into two successive steps. The preceding process is a cationic step in which an intermediate antimony dialkoxide is produced and the following a coordinated polymerization. The mean consumption of EO per catalyst at the inflection point was calculated to be 45 and was independent of the mole ratio of [TPP]/[TPAB]. It is assumed that TPP coordinates to the central antimony atom to produce an active complex salt in the second step. The effect of p-substitution of TPAB in the polymerization was also investigated; the Hammett parameters p for the first and the second polymerization step were found to be +1,7 and +1,0, respectively.

Notes: The copolymerization of methyl acrylate (MA) and isobutylene (IB) in the presence of Lewis acids (EtAlCl2, Et2AlCl, Et3Al, AlCl3, and ZnCl2) at low Lewis acid/MA mole ratio was investigated. EtAlCl2 and Et2AlCl were found to initiate the spontaneous reaction. An alternating copolymer was produced in this reaction when an excess of IB in the initial monomer feed was used. The copolymerization in the presence of Et3Al, AlCl3, and ZnCl2 did not proceed spontaneously and was initiated by dibenzoyl peroxide (BPO). In this case MA-rich copolymers are formed even in systems containing a large excess of IB in the monomer feed. The addition of BPO to systems containing ethylaluminium chlorides strongly diminishes the tendency towards alternating propagation. It was concluded that the mode of initiation has a significant influence on the copolymer composition. The alternating copolymerization by EtAlCl2 was studied in detail in order to determine the influence of the catalyst concentration, monomer feed ratio, reaction temperature and time on the monomer conversion, copolymer composition, molecular weight and tacticity.

Notes: N-Vinylcarbazole (NVC) is polymerised in the presence of pyridine at 60°C by using azodiisobutyronitrile (AIBN) and benzoyl peroxide (Bz2O2) as initiators and the results are compared with those obtained when benzene is used as the solvent. In the AIBN-initiated system using pyridine as the solvent the rates of polymerisation follow an usual linear relationship with respect to monomer concentration and a square root dependence with respect to the initiator concentration. In the Bz2O2-initiated system, however, deviations from these ideal behaviours are observed when benzene and pyridine, respectively, are used as the solvent. Initiation occurs through the complexation of the monomer with Bz2O2 and degradative transfer is thought to be mainly responsible for this unusual kinetic behaviour.

Notes: Esters of diacids and oligo(carboxylic acid)s substituted in α-position with Li, Na, or K (models of the propagation site in the anionic polymerization of methyl methacrylate (MMA)) were prepared, and their IR spectra were recorded. In the range 1600 - 1800 cm-1, their absorption of the Mt+ group in benzene solution was reflected in a band between 1630 and 1645 cm-1, depending on the counterion. In the presence of THF or of tert-butoxide of the same alkali metal this band appears between 1626 and 1660 cm-1. Coordination of the more remote alkoxycarbonyl group (e.g., in γ-position) to the counterion is demonstrated by a band near 1712 cm-1; its absorbance is much lower in the presence of THF. In solution, the metalloesters undergo autocondensation, the rate of which increases dramatically with the number of monomeric units. Thus, in benzene at 25 °C ethyl 2-lithioisobutyrate is stable for more than a week, whereas the half life of dimethyl 2-lithio-2,4,4-trimethylglutarate (Li-dimer, 3b) is 〈24 h, and the Li-trimer (5a), Li-tetramer (5b), and Li-pentamer (5c) completely decompose in less than 4 min under these conditions. The decomposition may be slowed down by adding tert-butoxide of the same alkali metal. In THF the decomposition proceeds much more quickly. The properties of models used in this study are compared with those of the propagation site in the anionic polymerization of MMA.

Notes: The capability of chloroalkenes to undergo cometathesis with alkenes was investigated with the intention to check the possibility of applying the principle of the synthesis of α,omega;-difunctional polybutadienes to α,omega;-dichloropolybutadienes. The results obtained from the analysis of the reaction products resulting from 1,6-dichloro-3-hexene (1)/4-octene (2) systems and WCl6/EtAlCl2 were compared with those obtained from 1-chloro-3-hexene (8) alone, 1/1,5-cyclooctadiène (13), 5-chloro-1-pentene (6)/2, and 1,4-dichloro-2-butene (10)/2 systems in the presence of WCl6/EtAlCl2. It was found that it is possible to apply the synthetic principle to α,omega;-bis-(δ-chloroalkenyl)polybutadienes.

Notes: Potassium carboxylates and 18-crown-6 form initiator systems for the anionic polymerization of oxiranes to afford polyethers with an acyloxy group at one of the chain ends. Because of the slow initiation as compared to the propagation step, the resulting polymers have wide molecular weight distributions (Mw/Mn ≈ 4,0). The presence of a small amount of water in the catalysts accelerates the initiation to give polymers with narrow molecular weight distributions (Mw/Mn ≤ 1,2). The polymerization of methyloxirane is accompanied by a significant chain-transfer reaction to the monomer, especially at high temperatures. Hexamethylcyclotrisiloxane is also polymerized by the same initiators. Furthermore, potassium salts of carboxylic acids initiate the polymerizations in the presence of a crown ether.

Notes: Among numerous polymers with cyclic polyethers and non-cyclic ethers as anchor groups, the condensation resin with dibenzo-18-crown-6 as anchor group (℗-DB-18-C-6), which can be easily prepared, exhibits the best properties for phase-transfer catalysis. It catalyses substitution, dichlorocarbene and polymerisation reactions which do not take place at all or only in a low yield without the catalyst. For substitution reaction the highest yields are up to 95% in the liquid phase and up to 70% in the gaseous phase. For chlorocarbene reactions yields up to 76% are reached. For the polymerisation of 2-pyrrolidone, started by potassium 2-pyrrolidonate, the yield is at 80%.

Notes: The polyamides 3-5 were synthesized from α,ω-diamino-substituted oligo(oxyethylene)s (1) and bis-chlorides of dicarboxylic acids (2). As copolymers with defined sequences they contain up to five oxyethylene units per repeating unit. Hereby properties like solubility, thermal stability and complexing ability towards alkali metal cations are influenced.

Notes: p-Cresol and eight oligo[(hydroxyphenylene)methylene] compounds 1b-e and 4a-d could be esterified with good yields with acryloyl chloride or propionyl chloride, respectively, in the presence of triethylamine. The simple and multiple acrylates and propionates were characterized by determination of their molar masses, elemental analyses, hydrogenation of the CC double bonds in the acrylate groups, and by their IR- and UV-spectra. No steric hindrance could be ascertained. Acrylates with more than three phenolic units in their molecules were found to have a range of melting, whereas all the propionates possess sharp melting points. This can be explained by polymerization of the acrylates which proceeds at room temperature without changing the appearance of the sample. The decadic molar absorption coefficients from the UV-spectra of the different homologous series were found to be proportional to the number of the phenolic units in their molecules.

Notes: N-Ethylaziridine (1) was polymerized in water with HCl as initiator and copolymerized with N-(2-hydroxyethyl)aziridine (2). Rapid propagation and termination reactions were observed. The maximum yield increases with the initiator concentration, whereas the molecular weight decreases. This is due to the difference in basicity between the tertiary N-atoms of the two monomers and the tertiary and the terminal secondary N-atoms of the polymers, which causes tranfer and termination reactions. Macrocycles with a side chain on a quaternary N-atom are formed. During the copolymerization, the more basic 1 is preferentially incorporated into the copolymer chain. The copolymerization parameters can be estimated roughly on the basis of basicity considerations: r1 〉 1; r2 〈 1. The ratio of the rate constants (propagation to termination) is lower for 1 than for 2. This is due to the fact that the basicity difference between the monomer and the tertiary N-atoms of the polymer is higher for 1 than for 2. By reaction of thionyl chloride with the copolymers the desired hydrochlorides of the N-(2-chloroethyl) derivatives are obtained. The neutralisation with alkali did not result the free bases, since the products formed are rather due to side reactions.

Notes: Transfer constants were determined from the thermal polymerization of methyl, ethyl, and butyl acrylates for methyl, ethyl, propyl, and isopropyl alcohols at 80 °C, utilising “mixedsolvent” systems wherever necessary. It was observed that the chain transfer constant for alcohols is not much affected by lengthening of the ester group in the acrylates, and the reactivity of the solvent is enhanced by an increased substitution at the α-carbon atom in the alkyl group.

Notes: Bovine trypsin-kallikrein inhibitor (TKI) was bound on three different water-soluble hydrophilic carriers derived from poly[N-(2-hydroxyethyl)-D,L-aspartamide] and containing a binding group (aromatic amine) and an additional modifying group (anionic or hydrophobic). The binding was performed by coupling of diazonium salts formed on the carrier with tyrosines in TKI. The product was characterized by means of sedimentation measurement, viscometry, electrophoresis, amino acid analysis, GPC, and antiproteolytic activity. TKI was found to be attached to the carrier by one or two tyrosines, the latter case being more frequent than it would correspond to independent random reactivity of the accessible tyrosines and the carrier molecules are crosslinked by the attached TKI. This is due to a fraction of two point attached TKI, as estimated according to a tree-like model. All three samples preserved good activity toward trypsin and chymotrypsin.

Notes: 1,3,5-Trioxane and 1,3-Dioxolane were polymerized in the melt in presence of different polyethylene glycols using BF3-etherate as catalyst. Thereby the polyethers are incorporated as blocks via a chain transfer reaction with their terminal hydroxyl groups. The addition of the polyethers drastically reduces the rate of polymerization. An investigation of the morphology of the melt-crystallized block copolymer by visible light microscopy was carried out. It could be shown that, in contrast to homopolymers and blends, not only the normal spherulitic crystallization occurs but also spiral type spherulites are formed. The latter depends on the molar mass of the total polymer and on the amount and chain-length of the polyether blocks.

Notes: In view of the structural resemblance of α-methylene-γ-butyrolactone to methyl methacrylate, conformation and NMR chemical shifts of poly(α-methylene-γ-butyrolactone-alt-styrene). are calculated and compared with those of poly(methyl methacrylate-alt-styrene). The conformational energy surfaces for the dyad sequence models of the both copolymers are analogous to each other, as is expected from the similarity in the constituting monomeric units. Agreement of calculation with observation is satisfactory with respect to the cotacticity-dependent splittings in the 13C NMR spectra and is improved by the fixation of a substituent in poly(α-methylene-γ-butyrolactone-alt-styrene). Calculation of 1H chemical shifts gives an alignment of NMR signals which is in accordance with the observation.

Notes: The kinetics of the reaction between hexamethylenediamine (HMD) and dibasic acids (malonic, succinic, glutaric, and adipic acid) were studied in the temperature range 18-42°C using 1-propanol as solvent. The total order of the reaction is two, first order in HMD and first order in the dibasic acid. The stoichiometry of the reaction is 1:1 and NMR and IR spectral analyses show that the product is an organic salt with and groups present. A mechanism was proposed in which a proton is transferred from the acid molecule to the base through a solvent molecule which acts as a bifunctional catalyst (both as a proton-acceptor and proton donor). Values of the rate constants, Arrhenius activation energies, preexponential factors, and entropies of activation are consistent with the proposed mechanism. There is a very strong evidence to show that the “half-anion” produced in the first ionization of the dicarboxylic acids is the real reactive species.

Notes: Symmetric Markov first order mechanisms are defined by equal conditional probabilities for the homotriad formation and a heterotacticity independent of homotacticity. The model predicts linear relationships between homotriad and diad fractions, restricted diad ranges, and a characteristic dependence of the persistence length on the diad fraction. Data on the syndiospecific propylene polymerization are in accordance with this model which also seems to describe heterotactic polymerizations.

Notes: Sorption isotherms and heats of immersion of water in poly(2-hydroxyethyl methacrylate) (PHEMA) and in poly[2-(2-hydroxyethoxy)ethyl methacrylate] (PHEOEMA) were determined at 25°C and the Gibbs energy, enthalpy and entropy of mixing were calculated from the data. The results confirm that the physical state of the polymer plays a decisive role in the thermodynamics of sorption. At the temperature of measurement, pure PHEMA is in the glassy state and after sorption of a certain amount of water it passes into the viscoelastic state. Similar to other cases of mixing of a glassy polymer with a low-molecular weight liquid, the entropy and enthalpy changes are negative, with contributions due to the difference between the physical states of both pure components predominating in them. The thermodynamics of liquid mixtures can be used only for PHEOEMA which at 25°C is in the viscoelastic state. The mixing of water (especially of the first additions) with PHEOEMA is exothermal, being at the same time connected with a negative residual entropy, the effect of which predominates at 25°C. As a result, the affinity of water to the polymer, expressed through a change in the Gibbs energy, is comparatively weak. This is why in this system no strongly bound water is involved, even if the ΔH and ΔS values indicate some sort of increase in ordering during mixing.

Notes: A version of DSC technique is proposed which ensures good accuracy in comparing the melting behaviour of two apparently similar samples. The information is obtained in the form of comparative thermograms recorded during simulataneous melting of both samples. The method is applied to observe the influence of cooling conditions and annealing on melting behaviour of low-density polyethylene.

Notes: The cyclic acetals 1,3-dioxolane (4a), 1,3-dioxane (4b), and 1,3-dioxepane (4c) give in their reactions with the methoxymethyl cation (1) a mixture of two isomeric tertiary oxonium ions: the simple products of cationation 5a-c and the cationated rings 6, 7, 9, enlarged by two atoms. The equilibria for the studied monomers are shifted to the side of the oxonium ions as shown in the reaction schemes 2, 4, 5, and 6 (SbF-6 or SbCIF-5 being the corresponding anions). In the case of 4a the equilibrium is displaced almost completely to the enlarged ring 6, whereas for the other two cyclic acetals 4b and 4c the first cationated products 5b and 5c dominate. Application of the dynamic 1H NMR method allows the determination of the equilibrium constants of the reaction of 4a with 1.

Notes: D-N-(4-vinylphenyl)carbamoylethylenedioxy(4-vinylphenyl)borane (1) with D-glyceric acid as template was copolymerized with technical divinylbenzene by a radical mechanism in the presence of various amounts of acetonitrile as an inert solvent. The resulting differences in the structure and swellability of the polymers are discussed in relation to the specificity of the polymers for the racemic resolution of D,L-glyceric acid. Some of these polymers were found to be able to bind glyceric acid with high optical enrichment by a covalent amide bond. To prevent the formation of the covalent amide bond during the intake reaction, the amide bond in the monomer is replaced by an ion pair relation. For this intention, the synthesis of an appropriate monomer 4-vinyltrimethylanilinium 2-(4-vinylphenyl)-1,3,2-dioxaborolan-4-carboxylate (2) and the investigation of the resulting polymers are described.

Notes: A series of novel semi-ladder polymers containing 7H-benzimidazo[2,1-a]benzo[d,e]isoquinolin-7-on-3,11-diyl units in the chain was prepared by one-step high temperature solution polycondensation of 4,4′-oxy-,4,4′-carbonyl-, and 4,4′-sulfonyldi-1,8-naphthalenedicarboxylic anhydride (1a-c) with 2,2′-diamino-4,4′-oxydianiline (2) or 2,2′-diamino-4,4′-hexafluoroisopropylidenedianiline (4). The similarity of the IR and UV spectra of the polymers and the model compounds 7a-c confirms the presence of the benzimidazobenzoisoquinolinone rings in the polymer chain. All the resulting polymers have excellent thermal stability both in argon and in air. The polymers prepared from 4 are soluble in 1-methyl-2-pyrrolidone and phenol/1,1,2,2-tetrachloroethane.

Notes: The stereoregularity of poly(α-methylstyrene)s prepared by anionic initiators was determined from the peak area of α-methyl proton absorptions and aromatic C1 carbon absorptions. Highly syndiotactic polymers were obtained at 0°C in both toluene and tetrahydrofuran (THF). Sodium, potassium, and cesium naphthalenes gave polymers with the same syndiotacticity in THF. The syndiotacticity of polymers prepared by sodium and potassium naphthalenes as catalyst in both toluene and THF decreased at low temperatures. This behavior is similar to that of o-methylstyrene and m-methylstyrene in THF. The stereoregulation mechanism in the anionic polymerization of α-methylstyrene is discussed and compared with that of polystyrene and ring substituted polystyrenes.

Notes: Ring-opened polymers of racemic and optically active 5,5-dimethylbicyclo[2.2.1]hept-2-ene (6) (5,5-dimethylnorbornene), with cis double bond contents of 0-100%, were prepared using various Mo-, W-, Re-, Os-, Ru-, and Ir-based olefin metathesis catalysts. The 13C NMR spectra of these polymers are interpreted in terms of TH, TT, HH, HT structures (T = tail, H = head, referring to the orientation of the methyl groups), also tt, tc, ct, cc structures (t = trans, c = cis double bonds), and m, r dyads (m = meso, r = racemic, referring to the relative configuration of adjacent cyclopentane rings in the chains). m/r splitting is observed for both the olefinic carbon (C3) and the adjacent ring carbon (C4) in the HH structures of the all-trans polymer made from racemic monomer using RuCl3 as catalyst. All-cis polymers are fully syndiotactic while all-trans polymers have 58% isotactic (m) and 42% syndiotactic (r) dyads. A consistent set of substitution parameters is derived, the effect of two methyl substituents on the 13C chemical shifts being generally a little less than the sum of the effects of the individual substituents.

Notes: The polymerization of maleic anhydride initiated by triphenylphosphine was investigated in acetic anhydride as well as in dimethylformamide. It was found that the polymer conversion increases with the increase of the concentration of monomer and initiator and the reaction temperature. It was also found that the rate of polymerization is higher in dimethylformamide than in acetic anhydride under the same set of experimental conditions. The apparent overall activation energy was found to be about 26,4kJ · mol-1 and 39,8 kJ · mol-1 in acetic anhydride and dimethylformamide, respectively. The polymerization rate depends upon the basicity of the initiator as well as on the dielectric constant of the solvent.

Notes: Casein-g-poly(vinyl acetate) was synthesized using potassium persulfate as initiator. Changes in monomer concentration, initiator concentration, backbone concentration, and temperature were effected. The rate of total conversion of monomer, the rate of homopolymerization and graft copolymerization, the grafting efficiency and the percentage of grafting were calculated. The grafting results were discussed in the light of grafting efficiency and percentage of grafting. They were found to be lower in the case of casein-g-poly(vinyl acetate) when compared to those of casein-g-poly(butyl acrylate).

Notes: Photochemical processes occurring in polystyrene films containing dicumyl peroxide (DCP), in the presence of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (Irganox 1076) were investigated. It was found, that Irganox 1076 reduces the photo-oxidation and photo-degradation of polystyrene when DCP is used as an initiator of the processes and polymer samples are irradiated with light of λ = 313 nm in air.

Notes: Hexakis(2,2,2-trifluorethoxy)cyclotriphosphazene (1b) reacts with borontrichloride at elevated temperatures to give a mixture of polymeric phosphazenes containing imino dichloro and imino bis(trifluoroethoxy)phosphoranetriyle units. The reaction was investigated by 31P NMR. Separation of several fractions of polymers was achieved by hexane/benzene solvent extraction. Molecular weights have been determined by means of membrane and/or vapor pressure osmometry. A reaction mechanism is discussed.

Notes: Polymers containing 3,3′-dioxo-5,5′-biindol-2,2′-diyl units were synthesized by high temperature polycondensation of 4,4′-diaminobiphenyl-3,3′-dicarboxylic acid (1) with ethylene dichloride and dibromide, 4-chloromethylbenzyl chloride and bromide, 4-chloromethyl-2,5-dimethylbenzyl chloride and bis(4-chloromethylphenyl) ether under different experimental conditions. These resulting polymers 5a-d were characterized by viscometric and IR Spectral studies and by TG in air. Kinetic parameters of their thermal degradation were evaluated.

Notes: The copolymerizations of 4(5)-vinyl-1,2,3-triazole, 1-p-bromophenyl-4-vinyl-1,2,3-triazole and 2-methyl-5-vinyltetrazole with styrene, methyl methacrylate and vinyl acetate have been examined and the corresponding copolymerization parameters r1, r2 were evaluated. The reactivities Q of these monomers are lower than that of styrene contrarily to other C-vinylheterocyclic monomers; it is assumed that it results from a limited stabilization of the corresponding radicals. In the case of 4(5)-vinyl-1,2,3-triazole, copolymerizations carried out at different temperatures and varied monomer concentrations show that intermolecular monomer association (as evidenced by NMR and IR measurements) does neither affect the copolymer composition nor the internal monomer triad structure of the copolymer.

Notes: Three different azophenols were oxidized by both the system CuCl/O2 in pyridine and electrochemically (as coherent films) on Fe and Cu anodes in water/methanol mixtures. Products of the chemical and anodic oxidative coupling process are in any case very near each other. Poly(oxy-4-phenylazo-1,2-phenylene) and its 3-allyl derivative are obtained from 4-hydroxyazobenzene (1) and 3-allyl-4-hydroxyazobenzene (2), respectively. The polymerization of 4-hydroxy-3,5-dimethylazobenzene (3) mainly proceeds through elimination of the phenylazo group and formation of poly(oxy-2,6-dimethyl-1,4-phenylene). By oxidation of 2 at Cu anodes thin, adherent films having very good protective features are obtained in short electrolysis times.

Notes: Water-soluble polyacrylamide samples of various molecular weight, containing salicylaldehyde and lysine moieties, were prepared by copolymerization of (Nα-5-methacryloylamino-salicylidene-N∊-methacryloyl-(S)-lysinato) (pyridine)copper (II) (1) with acrylamide, followed by destruction of the copper complex by the disodium salt of EDTA. It is shown that at pH 〉 6 the formation of “internal” aldimine occurs in these samples. The degree of assembly of “internal” Schiff base is considerably higher than in the model low-molecular weight system and does not depend on: a) the molecular weight of the polyacrylamide sample; b) the polymer concentration in buffer solution; c) the presence of a cross-linking agent. On the basis of these data a conclusion is made that in the copolymerization of 1 with acrylamide, methacryloyl moieties, bonded with the amino groups of salicylaldehyde and lysine, form macrocycles, the cyclocopolymerization rate being much higher than the rate of cross-linked polymer formation. After the removal of copper ions from the polymer the lysine and salicylaldehyde moieties remain attached to the same polymer chain in the immediate vicinity of each other, thus favouring the formation of “internal” aldimine.

Notes: Some configuration-dependent properties of poly(dimethylsiloxane) are evaluated by taking into account the full rotational range around skeletal bounds (ars model). Allocation of fractional electronic charges to Si, O and C atoms and consequent coulombic interactions give an essential contribution to the interpretation of experimental data. A comparison is drawn with the rotational isomeric state (ris) model adopted by many authors. A substantial equivalence between the two models is detected in the study of long polymer chains while some detectable difference arises in the description of short sequences.

Notes: The di(cyanomethyl) methylsuccinate derivative of cytosine and di(p-nitrophenyl) methyl-succinate derivative of hypoxanthine were prepared and polycondensed with a variety of diamines to provide powdery polyamides with molecular weights in the range of 1000-3100. The polyamides are soluble in DMSO and formic acid, but insoluble in ordinary organic solvents.