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 |
DOI | 10.1016/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. |
入库方式: OAI收割
来源:化学研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。