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Synthesis and properties of polyimides derived from cis- and trans-1,2,3,4-cyclohexanetetracarboxylic dianhydrides

文献类型:期刊论文

作者Fang, XZ; Yang, ZH; Zhang, SB; Gao, LX; Ding, MX
刊名POLYMER
出版日期2004-04-13
卷号45期号:8页码:2539-2549
关键词Isomerization Aliphatic Polyimides Cis- And Trans-1 2 3 4-chdas
ISSN号0032-3861
DOI10.1016/j.polymer.2004.02.008
英文摘要Cis-1,2,3,4-cyclohexanetetracarboxylic dianhydride (cis-1,2,3,4-CHDA) was synthesized. It was found that under such conditions as heating or boiling in acetic anhydride, cis-1,2,3,4-CHDA could be converted to its trans-isomer. The process of thermal isomerization was monitored by H-1 NMR spectra and the mechanism of conversion was proposed. Their absolute structures of cis- and trans-1,2,3,4-CHDAs were elucidated by single crystal X-ray diffraction. The polycondensations of cis- and trans-1,2,3,4-CHDAs with aromatic diamines such as 4,4'-oxydianiline (ODA), 4,4'-methylenedianiline (MDA), 4,4'-diamino-3,3'-dimethyldiphenylmethane (DMMDA), 4,4'-bis(4-aminophenoxy)benzene (TPEQ), 2,2-bis[4-(4-aminophenoxy)phenyl] propane (BAPP) were studied. It is easy to obtain higher molecular weight polyimides from trans-1,2,3,4-CHDA using conventional one-step or two-step methods. However, higher molecular weight polyimides derived from cis-1,2,3,4-CHDA could not be prepared by the usual methods (solid content ca. 10%) owing to the trend of forming cyclic oligomers. Increasing the concentration of monomers could give higher molecular weight cis-polymers. All of the cis-polyimides were soluble at room temperature in aprotic polar solvents and phenolic solvents and some of them even soluble in chloroform and tetrahydrofuran, while the corresponding trans-polymers showed poor solubility as compared to cis-polymers. All of the polyimides showed good thermal stability with the 5% weight loss temperatures in air over 415 degreesC. Furthermore, polyimides derived from cis-1,2,3,4-CHDA have higher glass transition temperatures (T(g)s) than corresponding trans-polyimides. The flexible polyimide films possessed a tensile modulus range of 2.1-3.6 GPa, a tensile strength range of 42-116 MPa, an elongation at break of 4-18%. These polyimides exhibited cutoffs at wavelengths around 270 nm and were entirely colorless. All the polyimides showed amorphous pattern according to Wide angle X-ray diffraction measurements. The differences of polymerization and properties were explained by the structural changes resulted from isomerism. (C) 2004 Elsevier Ltd. All rights reserved.
语种英语
WOS记录号WOS:000220533500009
出版者ELSEVIER SCI LTD
源URL[http://ir.iccas.ac.cn/handle/121111/82227]  
专题中国科学院化学研究所
通讯作者Ding, MX
作者单位Chinese Acad Sci, Changchun Inst Appl Chem, State Key Lab Polymer Phys & Chem, Changchun 130022, Peoples R China
推荐引用方式
GB/T 7714
Fang, XZ,Yang, ZH,Zhang, SB,et al. Synthesis and properties of polyimides derived from cis- and trans-1,2,3,4-cyclohexanetetracarboxylic dianhydrides[J]. POLYMER,2004,45(8):2539-2549.
APA Fang, XZ,Yang, ZH,Zhang, SB,Gao, LX,&Ding, MX.(2004).Synthesis and properties of polyimides derived from cis- and trans-1,2,3,4-cyclohexanetetracarboxylic dianhydrides.POLYMER,45(8),2539-2549.
MLA Fang, XZ,et al."Synthesis and properties of polyimides derived from cis- and trans-1,2,3,4-cyclohexanetetracarboxylic dianhydrides".POLYMER 45.8(2004):2539-2549.

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来源:化学研究所

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