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  • glass transition temperature  (5)
  • Wiley-Blackwell  (5)
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  • Wiley-Blackwell  (5)
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  • 1
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 31 (1993), S. 183-191 
    ISSN: 0887-624X
    Keywords: smectic ; liquid crystal ; acrylate ; biphenol mesogen ; glass transition temperature ; density ; crosslinked ; photopolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Difunctional acrylates and methacrylate monomers have been made which are high order smectic liquid crystal (or crystalline) at room temperature. This report discusses materials with the following structure: F-S-M-S-F, where F is a functional group, acrylate or methacrylate (A or M); S is a spacer (CH2)n(n), and M is a mesogen - in this case 4,4′-dioxybiphenyl (B). They are codified as BnA or BnM where n is the number of methylenes in the spacer. High conversion with high Tg can be obtained when polymerizing in the smectic state because the reactive end groups are concentrated in a small volume and can react well with little or no diffusion. B2A, B3A, B6A, B11A, and B3M were polymerized in the smectic state and compared to polymers made at temperatures where the monomers were isotropic. High conversion was obtained below final Tg - even then, probably because the polymers were ordered. All the polymers were studied by WAXD and dynamic mechanical spectroscopy. Solid-state NMR on B3A showed that there was very high conversion of the double bonds at all temperatures. B3A photopolymerized in the smectic state (60-76°C) produced a crystalline polymer with Tg = 185°C (1 Hz). When photopolymerized at 85°C, above the isotropization temperature (Ti), a poorly organized polymer was obtained with a Tg of 155°C (1 Hz). Monomers with an odd number of methylene groups as spacers were crystalline after polymerization. With an even number of methylene groups, they lost most of their crystallinity on polymerization below Ti, but retained a low order smectic structure. Similar structures were obtained with all the monomers when they were polymerized above Ti. There was little effect of polymerization temperature on Tg when the spacers had an even number of methylene groups. © 1993 John Wiley & Sons, Inc.
    Additional Material: 14 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 793-801 
    ISSN: 0887-624X
    Keywords: poly(oxyethylene) ; thioether ; sulfoxide ; sulfone ; copolymer ; solubility ; glass transition temperature ; substitution ; oxidation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly[oxy(ethylthiomethyl)ethylene] (ETE) was prepared from poly[oxy (chloromethyl)ethylene] (CE) by reaction with sodium ethanethiolate. Sulfoxide and sulfone analogues were synthesized by oxidation of the poly[oxy(ethylthiomethyl)ethylene]. By changing the chloromethyl/sodium ethanethiolate ratio, poly[oxy (chloromethyl)ethylene-co-oxy(ethylthiomethyl)ethylene] (CE-ETEs) were easily made. Poly[oxy(ethylsulfinylmethyl)ethylene] (ESXE), poly[oxy(chloromethyl)ethylene-co-oxy(ethylsulfinylmethyl)ethylene] (CE-ESXEs), poly[oxy(ethylsulfonylmethyl)ethylene] (ESE), and poly[oxy(chloromethyl)ethylene-co-oxy(ethylsulfonylmethyl)ethylene] (CE-ESEs) were obtained by oxidation of ETE or CE-ETEs. There was little if any chain degradation. The (co)polymer structures were confirmed by FTIR and 1H-NMR spectroscopic studies. Their thermal properties were studied by DSC and TGA. Tgs of ETE, ESXE, and ESE were -57, 36, and 57°C, respectively, and Td,os (initial decomposition temperature, TGA) were 331, 198, and 308°C, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 793-801, 1998
    Additional Material: 7 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 495-504 
    ISSN: 0887-624X
    Keywords: copolymer ; glass transition temperature ; Fox equation ; sulfone ; thioether ; oxyethylene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New classes of copolymers, poly[oxy(chloromethyl)ethylene]/poly[oxy-((alkylthio)methyl)ethylene] copolymers (CE-ATEs), poly[oxy((alkylthio)methyl)-ethylene]s (ATEs), poly[oxy(chloromethyl)ethylene]/poly[oxy((alkylsulfonyl)meth-yl)ethylene] copolymers (CE-ASEs), and poly[oxy((alkylsulfonyl)methyl)ethylene]s (ASEs) have been made for the first time. The thioether-containing polymers (CE-ATEs and ATEs) were synthesized by reacting poly[oxy(chloromethyl)ethylene] (CE, poly(epichlorohydrin)) with different amounts of sodium alkanethiolates. The sulfone-containing polymers (CE-ASEs and ASEs) were synthesized by oxidizing the CE-ATEs and ATEs using m-chloroperoxybenzoic acid. The Fox equation, a linear relationship, fit the Tg/composition data for most CE-ATEs. The Tg's of the CE-ASEs showed positive deviations from those calculated using the Fox equation. The Johnston equation, in which steric and/or polar interactions between dissimilar monomeric units are considered by using TgAB (the Tg of the AB or BA dyad), fit the Tg/composition data for all copolymers in this study. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 495-504, 1998
    Additional Material: 6 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 32 (1994), S. 1531-1537 
    ISSN: 0887-624X
    Keywords: 1,3-bis(3 hydroxy propyl sulfonyl)propane ; 1,4-bis(3-hydroxypropyl sulfonyl)butane ; 1,3-propane dithiol ; 1,4-butane dithiol ; poly(urethane) ; poly sulfone ; methylene diphenyl diisocyanate (MDI) ; toluene diisocyanate (TDI) ; hexamethylene diisocyanate (HMDI) ; melt temperature ; glass transition temperature ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Eight poly(urethane-sulfone)s were synthesized from two sulfone-containing diols, 1,3-bis(3-hydroxypropylsulfonyl)propane (Diol-333) and 1,4-bis(3-hydroxypropylsulfonyl)butane (Diol-343), and three diisocyanates, 1,6-hexamethylene diisocyanate (HMDI), 4,4′-diphenylmethane diisocyanate (MDI), and tolylene diisocyanate (TDI, 2,4- 80%; 2,6-20%). As a comparison, eight polyurethanes were also synthesized from two alkanediols, 1,9-nonanediol and 1,10-decanediol, and three diisocyanates. Diol-333 and Diol-343 were prepared by the addition of 1,3-propanedithiol or 1,4-butanedithiol to allyl alcohol and subsequent oxidation of the resulting sulfide-containing diols. The homopoly(urethanesulfone)s from HMDI and MDI are semicrystalline, and are soluble in m-cresol and hot DMF, DMAC, and DMSO. The copoly(urethane-sulfone)s from a 1/1 molar ratio mixture of Diol-333 and Diol-343 with HMDI or MDI have lower crystallinity and better solubility than the corresponding homopoly(urethane-sulfone)s. The poly(urethane-sulfone)s from TDI are amorphous, and are readily soluble in m-cresol, DMF, DMAC, and DMSO at room temperature. Differential scanning calorimetry data showed that poly(urethane-sulfone)s have higher glass transition temperatures and melting points than the corresponding polyurethanes without sulfone groups. The rise in glass transition temperature is 20-25°C while the rise in melting temperature is 46-71°C. © 1994 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 36 (1998), S. 75-83 
    ISSN: 0887-6266
    Keywords: barrier polymer ; permeability coefficient ; glass transition temperature ; blend ; sulfone ; oxyethylene ; oxytrimethylene ; Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Gas barrier properties of alkylsulfonylmethyl-substituted poly(oxyalkylene)s are discussed. Oxygen permeability coefficients of three methylsulfonylmethyl-substituted poly(oxyalkylene)s, poly[oxy(methylsulfonylmethyl)ethylene] (MSE), poly[oxy(methylsulfonylmethyl)ethylene-co-oxyethylene] (MSEE), and poly[oxy-2,2-bis (methylsulfonylmethyl)trimethylene oxide] (MST) were measured. MSEE, which has the most flexible backbone of the three polymers, had an oxygen permeability coefficient at 30°C of 0.0036 × 10-13 cm3(STP)·cm/cm2·s·Pa higher than that of MSE, 0.0014 × 10-13 cm3(STP)·cm/cm2·s·Pa, because the former polymer's Tg was near room temperature. MST with two polar groups per repeat unit and the highest Tg showed the highest oxygen permeability, 0.013 × 10-13 cm3(STP) · cm/cm2·s·Pa, among the three polymers, probably because steric hindrance between the side chains made the chain packing inefficient. As the side chain length of poly[oxy(alkylsulfonylmethyl)ethylene] increased, Tg and density decreased and the oxygen permeability coefficients increased. The oxygen permeability coefficient of MSE at high humidity (84% relative humidity) was seven times higher than when it was dry because absorbed water lowered its Tg. At 100% relative humidity MSE equilibrated to a Tg of 15°C after 2 weeks. A 50/50 blend of MSE/MST had oxygen barrier properties better than the individual polymers (O2 permeability coefficient is 0.0007 × 10-13 cm3(STP)·cm/cm2 ·s·Pa), lower than most commercial high barrier polymers. At 100% relative humidity, it equilibrated to a Tg of 42°C, well above room temperature. These are polymer systems with high gas barrier properties under both dry and wet conditions. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 75-83, 1998
    Additional Material: 5 Ill.
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