Investigation on cyclization process of co-polyimides containing 2-(4-aminophenyl)-5-aminobenzimidazole units
Investigation on cyclization process of co-polyimides containing 2-(4-aminophenyl)-5-aminobenzimidazole units
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含2-(4-氨基苯基)-5-氨基苯并咪唑单元的共聚酰亚胺环化过程的研究
DOI：
10.1177/0954008314520790
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发表时间：
2014-08
影响因子：
2.1
通讯作者：
Zhang Qinghua
中科院分区：
文献类型：
--
作者：
Dong Jie;Xu Yuan;Xia Qingming;Yin Chaoqing;Zhang Qinghua
聚酰亚胺作为一种高性能聚合物，在各个领域得到了广泛的应用。环化反应对聚合物的化学结构和物理性能的变化起着重要的作用。通过在均苯四甲酸二酐（PMDA）和4，4 ′-二氨基二苯醚（ODA）均聚酰亚胺主链上引入芳香杂环二胺单体（2-（4-氨基苯基）-5-氨基苯并咪唑（BIA）），合成了一系列无规共聚酰胺酸（PAA）。采用傅里叶变换红外光谱（FTIR）研究了180-300°C温度范围内的环化反应动力学。结果表明，BIA的加入降低了环化反应速率，这主要归因于BIA的刚性棒状结构。采用二维相关红外光谱法研究了固态共PAA的热亚胺化反应机理。异步光谱中交叉峰的符号表明，酰亚胺相关模式的变化先于酰胺模式，这表明环化发生在酰胺质子被夺取之前。结果表明，在PMDA-ODA链段中引入BIA单元后，PAA的间位链段进入相应聚酰亚胺的障碍明显增加，这是环化反应速率降低的根本原因。
As one type of high-performance polymers, polyimides have been extensively used in various fields. The cyclization reaction plays a significant role in the change of the polymeric chemical structure and physical properties. In this work, a series of random co-poly(amic acid)s (PAAs) were synthesized by introducing an aromatic heterocyclic diamine monomer (2-(4-aminophenyl)-5-aminobenzimidazole (BIA)) into the homopolyimide backbones of pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA). Fourier transform infrared (FTIR) spectroscopy was employed to study the cyclization kinetics in the temperature range of 180–300°C. The results indicate that the addition of BIA decreases the cyclization rates, which is mainly attributed to the rigid-rod structure of the BIA. The mechanism of thermal imidization of the solid state co-PAA was also studied by FTIR using two-dimensional correlation spectroscopy method. The signs of the cross peaks in asynchronous spectra suggested that the imide-related modes changed prior to the amide mode, which indicates that cyclization occurred before the amide proton was abstracted. The result illustrates the truth that the introduction of BIA units into PMDA-ODA segments obviously increases the barrier for the meta-segment of PAA into corresponding polyimide, which is the essential reason for the decreasing cyclization rate.
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DOI：
--
发表时间：
1993-03
期刊：
--
影响因子：
--
作者：
M. I. Bessonov;V. Zubkov
通讯作者：
M. I. Bessonov;V. Zubkov
DOI：
10.1002/polb.20655
发表时间：
2005-12
期刊：
Journal of Polymer Science Part B
影响因子：
--
作者：
Yun Lu;M. Zhan
通讯作者：
Yun Lu;M. Zhan
DOI：
10.1002/pola.1987.080250720
发表时间：
1987-07-01
影响因子：
--
作者：
BREKNER, MJ;FEGER, C
通讯作者：
FEGER, C
影响因子：
1.7
作者：
K. Yu;Yang Hyun Yoo;J. Rhee;Myong-Hoon Lee;Soo-chang Yu
通讯作者：
K. Yu;Yang Hyun Yoo;J. Rhee;Myong-Hoon Lee;Soo-chang Yu
影响因子：
4.6
作者：
Kotera, M;Nishino, T;Nakamae, K
通讯作者：
Nakamae, K