SYNTHESIS OF MESOGENIC POLYESTERS WITH 2-DICHLOROMETHYLHYDROQUINONE MOIETIES

A series of novel mesogenic polyesters with 2-dich1oromethylhydroquinone moieties weresynthesized by polycondensation of the novel diacyl chloride monomer 2-dichloromethyl-1, 4-bis (4'-chloroformylbenzoyl) oxybenzene-(I) with α,ω-polymethylenediols including ethyleneglycol, 1, 4-butanediol, 1, 6-hexanediol and 1, 10-decanediol. The diacyl chloride monomerwas synthesized by simultaneous transformations of both the carboxy and formaldehydegroups of 2-formyl-1, 4-bis (4'-carboxybenzoyl) oxybenzene into acyl chloride anddichloromethyl groups respectively. The syntheses of the monomer (I) and the polymers werereported.     

SYNTHESIS OF A GROUP OF MESOGEN JACKETED LIQUID CRYSTAL POLYMERS

A group of the mesogen jacketed liquid crystal polymers based on the monomers 2,5-bis (4-substituted benzoyl)oxystyrenes are synthesized. The substituents include alkoxy, alkyl, and cyano groups. The synthesis and the primary characterization of the liquid crystal phase of the monomers and the polymers are described. While some of the monomers give smectic textures the polymers are found to be nematic above their melting or glass transition temperatures. Interestingly the unsubstituted monomer and its polymer poly 2,5-di( benzoyloxy ) styrene are also liquid crystalline. The single crystal structure of one of the monomers is also discussed.     

IUPAC 国际功能高分子分子设计讨论会在汉城召开

1989年6月26～28日在南朝鲜汉城召开了一次有来自南朝鲜以及中、美、苏、日等20个国家和地区的800余名代表参加的 IUPAC 功能高分子分子设计国际会议。出席会议的我国代表有中科院钱人元教授和高校系统的冯新德、沈家骢、卓仁禧三位教授以及作者5人。会议主席由南朝鲜高分子学会会长、国内汉城大学教授安泰玩博士担任。现任 IUPAC 高分子学会主席三枝武夫教授出席会议致词并作了大会报告。     

TRANSITIONS AND MODRPHOLOGY OF MAIN-CHAIN LIQUID CRYSTALLINE POLYMERS WITH X-SHAPED MESOGENS

The transitions and morphology of a series of main-chain liquid crystalline polymer with X-shaped mesogens were studied by means of DSC,SALS and polarizing microscopy techniques. Aneven-odd effect was observed for samples with different size of the substituents on the mesogenends. The isotropization process was similar to that of main-chain polymers with rod-likemesogens. No crystallization was detected for specimens cooling down from their isotropic meltstate. However two of the samples may crystallize in cooling process directly from the liquidcrystalline state.