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  • 1
    Electronic Resource
    Electronic Resource
    Viscoelastic properties of short fiber filled SBR composites (1988)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 160 (1988), S. 29-39 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: In der vorliegenden Arbeit wird der Einfluß der Verformungsamplitude, der Temperatur und der Frequenz auf die dynamischen Eigenschaften von SBR-Faserverbundstoffen untersucht. Der Einbau von Kurzfasern erhöht den Speichermodul bei beliebiger Verformungsamplitude. Je nach Fasertyp verringert sich die lineare Reaktionszone des Moduls auf die Verformung oder verschwindet vollkommen. Der Verlustfaktor tan δ ist größer bei Faserverbundstoffen, obwol die Signale größenmäßig sich nicht verändern, lediglich die entsprechende Verformung.Bei Temperaturanstieg verringert sich der Modulwert, jedoch ist dieser Abfall weniger stark ausgeprägt im Faser-SBR-Verbund. Die Relaxationsspektren zeigen eine maximale Dämpfung, die der Hauptrelaxation in der Elastomermatrix entspricht. Die Temperatur,bei der dieses Maximum auftritt, verlagert sich zu höheren Werten mitsteigender Anregungsfrequenz. Dadurch wird die Ermittlung der scheinbaren Relaxationsaktivierungsenergie möglich, die im Verbund Faser-Haftmittel-SBR höher ist (225-275 kJ/mol) als in dem faserfreien Stoff (194.6 kJ/mol) als Folge einer stärkeren Faser-Matrix-Wechselwirkung.
    Notes: This paper examines the effects of deformation amplitude, temperature and frequency on the dynamic properties of SBR-short fiber composites. The presence of the fiber increases the storage modulus at any deformation amplitude. Depending on the nature of the fiber, the linear response zone of the modulus versus deformation either diminishes or disappears. The loss factor tan δ is higher in fiber composites. Although the peaks do not vary in magnitude, they occur at different deformation amplitudes.Temperature increase causes the moduli to decrease, the gradient, however, being less pronounced for fiber composites. The relaxation spectra show a damping peak which correlates to the principal relaxation process in the elastomeric matrix. The temperature at which this peak appears is displaced towards higher values with increasing excitation frequency. This allows the determination of the apparent relaxation activation energy, which is higher in fiber plus adhesive composites (225 - 275 kJ/mol), as compared to the fiber-free composite (194 kJ/mol), as a consequence of stronger fiber-matrix interaction.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1988.051600103
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  • 2
    Electronic Resource
    Electronic Resource
    Liquid crystalline polymers containing heterocycloalkanediyl groups as mesogens, 1. Liquid crystalline polymethacrylates and polyacrylates containing 1,3-dioxane-2,5-diyl groups as mesogens in the side chain (1987)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 1017-1031 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Polymethacrylates and polyacrylates containing 4-[5-(4-methoxyphenyl)-1,3-dioxan-2-yl]-phenol moieties as mesogenic units and an aliphatic spacer containing eleven methylene units were synthesized. Their phase behavior was studied by differential scanning calorimetry and optical polarizing microscopy, and compared with the phase behavior of the corresponding polymethacrylates and polyacrylates containing 4′-methoxy-4-biphenylol as mesogens. All polymers present smectic mesomorphism. The substituted 2,5-diphenyl-1,3-dioxane mesogen resembles a terphenyl mesogen in which the internal phenyl ring is hydrogenated. Even so, when compared with polymers containing biphenyl moieties, the glass transition temperatures of the polymers containing 1,3-dioxane moieties are lower, although their isotropization occurs at higher temperatures.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1987.021880507
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  • 3
    Electronic Resource
    Electronic Resource
    The sequence length-distribution in eutectoid copolymers as obtained from an analysis of the melting processDedicated to Prof. Dr. H. J. Cantow on the occasion of his 65th birthday (1988)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 189 (1988), S. 2627-2645 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Thermodynamics of eutectoid copolymers is based on the assumption that the co-units are eutectic units. At low concentration of one of these units (non-crystallizable units, nc-units), crystallizable sequences (c-sequences) are formed. Segregation of the eutectic units leads to lamella-shaped extended c-sequence crystals, the thickness distribution of which is controlled by the c-sequence length-distribution (“structure-c-sequence length relationship”). According to thermodynamics the lamellar crystals have to melt selectively and consecutively with respect to their mean thickness. For eutectoid copolymers it is, therefore, possible to deduce the c-sequence length-distribution from a thermodynamic analysis of the whole melting process. A computer-aided method of analyzing differential scanning calorimetry measurements is applied to various semicrystalline copolymers (low-density polyethylene (LDPE), vicinal-chlorinated polyethylene, copolymers with —OCH2— units). Theoretical structure parameters (crystallinity, mean crystal thickness) and small-angle X-ray scattering (SAXS) -pattern computed from the c-sequence length-distribution are shown to be in good accord with the experimental data. The universal features of the crystallization behaviour of eutectoid copolymers are emphasized. The influence of topochemical reactions onto the distribution of the eutectic co-units of copolymers containing oxymethylene units is discussed.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1988.021891111
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  • 4
    Electronic Resource
    Electronic Resource
    Electron beam lithographic evaluation and chain scissioning yields of itaconate resistsThis paper is a revision of Paper 469-18 which was presented at the SPIE conference on Advances in Resist Technology, March 12-13, 1984 in Santa Clara, Ca. (1985)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 30 (1985), S. 4631-4641 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Copolymers of itaconic acid with methyl methacrylate, P(ItA-MMA), have been synthesized as promising positive working electron beam resists.1,2 However, attempts to obtain greater electron beam sensitivity by increasing the itaconic acid content and initial molecular weight of these copolymers have been hindered by difficulties in synthesizing itaconic acid copolymers with an ItA content greater than 50 mol% or with a molecular weight above 250,000. The usefulness of the MMA-ItA copolymers is also limited by their susceptibility to anhydride formation which makes this resist very sensitive to prebake conditions and aging times. To overcome these limitations and to develop resist materials with improved sensitivity, alkyl ester derivatives of itaconic acid have been synthesized, both as homopolymers and as copolymers with methyl methacrylate. The electron-beam chain scissioning yields, G(s), of these derivatives have been determined, and the most promising of these copolymers and homopolymers have been evaluated for lithographic performance. The G(s) values of the alkyl itaconate copolymers depend greatly on the structure of the alkyl group. The mono-alkyl itaconate copolymers exhibit G(s) values 2-3 times greater than the corresponding dialkyl itaconate copolymers. In particular, copolymers of monomethyl itaconate (MeI) with methyl methacrylate are found to be promising resist materials with high sensitivities and compatability with processing conditions. A trend in sensitivity is observed for a series of MMA-MeI copolymers ranging from 20 to 85 mol % MeI, with a maximum sensitivity observed for the 57 and 73% MeI compositions. These copolymers exhibit improved sensitivity over that of the itaconic acid copolymers. Anhydride is formed less readily from the MeI copolymers than from the ItA copolymers, improving the stability of the resist for process conditions. Areas exposed in P(MMA-73 mol % MeI) at 4 μC/cm2 (20 kV) were developed with less than 10% thinning of unexposed resist and with a contrast (γ) of 2. Vertical walls were observed for 1 μm wide lines using P(MMA μ73% MeI) at a dose of about 6 μC/cm2.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1985.070301210
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  • 5
    Electronic Resource
    Electronic Resource
    Thermal effects in polytetrafluoroethylene at high hydrostatic pressures (1986)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 32 (1986), S. 4049-4061 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The temperature changes as a result of rapid hydrostatic pressure applications are reported for polytetrafluroethylene (PTFE, Teflon) in the reference temperature range from 294° to 381°K and in the pressure range from 13.8 to 200 MN/m2. The thermal effects were found to be higher at the reference temperature approximating the transition temperatures of 19° and 30°C than at higher reference temperature. The data were analyzed by determining the predicted thermoelastic coefficients derived from the Thomson equation (∂T/∂P = αT/ρCp). A curvefitting analysis showed that the empirical curve, (∂T/∂P) = ab(ΔP)b-1, described the experimental thermoelastic coefficients obtained from the experiments. The fact that no agreement was found between the predicted and the experimental coefficients is due to the physical changes in PTFE at the transition temperatures. The relationship between the thermal effects and the chain molecular motion is discussed by including dynamic mechanical analysis and differential scanning calorimetry DSC measurements for the PTFE samples.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1986.070320321
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  • 6
    Electronic Resource
    Electronic Resource
    Thickening reaction of unsaturated polyester resins with inorganic oxides and the rubber elasticity theory (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 34 (1987), S. 881-886 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1987.070340237
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  • 7
    Electronic Resource
    Electronic Resource
    Measuring and modelling the transition layer during the dissolution of glassy polymer filmsThis paper was presented in part at the National Meeting of the American Institute of Chemical Engineers, Boston, August 24-27, 1986. (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 35 (1988), S. 641-651 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The technique of laser interferometry is now used routinely by the microelectronics industry for the measurement of the dissolution rates of thin polymer films. In addition to the rate of dissolution, laser interferometry can also provide quantitative information on the thickness of the transition layer between the dissolving glassy polymer and the liquid solvent. This paper describes how observed patterns of reflected light intensity may be analyzed to calculate the thickness of the transition layer for polymers that dissolve with little or no swelling. The technique requires knowledge of the shape of the concentration profile in the transition layer. However, by assuming various simple model profiles one may obtain a reasonable estimate. Experimental measurements of poly(methyl methacrylate) (PMMA) films dissolving in methylethyl ketone indicate transition layers of thicknesses 0 to 0.1 μm for PMMA of molecular weights Mw = 37,000 to 1,400,000.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070350307
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  • 8
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of liquid crystalline poly(N-acylethyleneimine)s (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 2269-2279 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of three cyclic imino ethers containing mesogenic groups attached to the heterocyclic unit through flexible spacers is described. Cationic ring-opening isomerization polymerization of two of them, i.e., 2-[4-(4-methoxy-4′-biphenyloxy)butyl]-2-oxazoline (MeOBiph-4-Oxz) and 2-[6-(4-methoxy-4′-biphenyloxy)hexyl]-2-oxazoline (MeOBiPh-6-Oxz) provided thermotropic liquid crystalline (LC) poly(N-acylethyleneimine)s, whereas the polymerization of 2-[4-(4-phenylphenoxy)butyl]-2-oxazoline (BiPh-4-Oxz) led to a crystalline polymer.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250823
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  • 9
    Electronic Resource
    Electronic Resource
    Interchain electron donor-acceptor complexes. Determination of equilibrium constant and thermodynamic parameters in the solid state (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 935-951 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interpolymeric electron donor-acceptor (EDA) complex of donor poly[(N-ethylcarbazol-3-yl)methyl methacrylate] (PHMCM-2) with acceptor poly-(2-[(3,5-dinitrobenzoyl)oxy]ethyl methacrylate) (PDNBM-2) presents a single glass transition temperature and a decomplexation endotherm on differential scanning calorimetric (DSC) thermograms. This system is considered a “polymer blend model” which exhibits a lower critical solution temperature (LCST). Phase separation of this blend is kinetically controlled and positive deviations of the glass transition temperatures from weight average values suggest that it behaves as a thermally reversible crosslinked network. Calorimetric methods to determine the heats of mixing of small molecule complexes in solution were adapted for this solid state blend to estimate the equilibrium constant (Keq) and other thermodynamic parameters. Applying a computer iterative procedure and assuming 1 : 1 stoichiometry, a least-squares fit was found for several different donor molecular weights with three different high molecular weight acceptors. At moderate molecular weights, Keq rises to represent saturation fractions near unity as found in biological systems. Keq decreases for higher molecular weights, possibly due to trapped chain entanglements. These results are supported by a composition-independent, “horizontal line” phase diagram, thus resembling the completely complexed/denaturation process in DNA.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260320
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  • 10
    Electronic Resource
    Electronic Resource
    A kinetic study of the copolymerization of maleic anhydride with ethyl vinyl ether using the rotating-sector techniquePaper presented before the Division of Polymer Chemistry, American Chemical Society Meeting, Toronto, Ontario, Canada, in June 1988. (1989)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 27 (1989), S. 2093-2108 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The results of polymerization and initiation experiments at 25°C show that the alternating copolymerization of maleic anhydride (monomer 1) and ethyl vinyl ether (monomer 2) is consistent with a theoretical mechanism defined by the usual rate constants (in L/mol s): Propagation: (kp)11 = 0.00; (kp)12 = 1.66 × 105, (kp)22 = 2.0 × 103; and (kp)21 = 2.04 × 105. Termination (kt)11 = 7.40 × 1010; (kt)12 = 52.8 × 1010; (kt)22 = 1.33 × 1010. The relative magnitudes of the two cross-propagation constants and the three termination constants are consistent with accepted theory with regard to polarity, resonance, and steric factors. The steady-state and rotating-sector experiments were carried out in a dilatometer using azobisdiisobutyronitrile as the initiator, acetone as the solvent, and UV light of 365 nm wave length.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1989.080270627
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