ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The synthesis of telechellcs of poly(ether-ether-sulfones) (PEES) is controlled by high-resolution gel-permeation chromatography to optimize for low content of side products. Under optimum conditions the bifunctional polymer-homologous series is formed to 99,9%. These telechrcs were used to synthesize block copolymers with aromatic polyesters. The polyesters (PE) contain phenylhdroquinone and terephthalic acid (semicrystalline liquid-crystalline (LC) polyester), phenylterephthalic acid (amorphous LC polyester) or isophthalic acid (amorphous non-LC polyester). Block copolymers with amorphous polyesters show one glass transition temperature depending on the composition but blends of corresponding homopolymers are biphase. Block copolymers with semicrystalline LC polyesters are phase-separated. Incorporation of semicrystalline LC polyester segments into PEES increases their solvent resistance. The storage modulus of the block copolymer with 50 wt.-% of the semicrystalline polyester shows the same temperature dependence as PEES. Homogeneous block copolymers show anisotropy only if the weight fraction of polyester is larger than 0,5 whereas phase-separated systems show anisotropy at smaller fractions of polyester.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1994.021950417
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