The dominant factor for mechanical property of polyimide films containing heterocyclic moieties: In-plane orientation, crystallization, or hydrogen bonding
The dominant factor for mechanical property of polyimide films containing heterocyclic moieties: In-plane orientation, crystallization, or hydrogen bonding
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含杂环部分的聚酰亚胺薄膜机械性能的主导因素：面内取向、结晶或氢键
DOI：
10.1002/app.44000
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发表时间：
2016-10-15
影响因子：
3
通讯作者：
Liu, Xiangyang
中科院分区：
文献类型：
--
作者：
Luo, Longbo;Zhang, Jing;Liu, Xiangyang
结晶、面内取向和氢键相互作用是提高聚酰亚胺（PI）薄膜力学性能的三个重要因素。然而，哪一个是主导因素？本研究选取三种含杂环结构的聚酰亚胺薄膜，聚苯并恶唑酰亚胺、聚苯并咪唑酰亚胺和聚嘧啶酰亚胺进行对比研究。聚（苯并恶唑-酰亚胺），聚（苯并咪唑-酰亚胺），和聚（嘧啶-酰亚胺）PI膜的结晶度分别为36%，24%和15%。小角X射线散射结果表明，聚苯并恶唑酰亚胺和聚苯并咪唑酰亚胺薄膜具有周期性层状结构，而聚嘧啶酰亚胺薄膜由于结晶度低，没有长周期结构。面内取向（P200）由偏振衰减全反射（ATR）-傅里叶变换红外和折射率计算。面内取向的顺序为聚（苯并咪唑-酰亚胺）<聚（苯并恶唑-酰亚胺）<聚（嘧啶-酰亚胺）。氢键相互作用，限制链运动和阻碍自发的面内取向，只形成在聚（苯并咪唑-酰亚胺）。讨论了三种影响因素与PI薄膜力学性能的关系，得出了氢键作用对PI薄膜力学性能影响程度的大小顺序为：氢键作用<结晶度<面内取向。提出了两种PI薄膜的结构模型，以进一步证实面内取向对力学性能的主导作用。© 2016 Wiley Periodicals，Inc. J.应用聚合物Sci. 2016，133，44000。
Crystallization, in-plane orientation, and hydrogen bonding interactions are three vital factors for enhancing mechanical properties of polyimide (PI) films. However, which is the dominant factor? In this study, three PI films containing heterocyclic moiety, poly(benzoxazole-imide), poly(benzimidazole-imide), and poly(pyrimidine-imide) were chosen to comparative study. The crystallinity of poly(benzoxazole-imide), poly(benzimidazole-imide), and poly(pyrimidine-imide) PI films are 36, 24, and 15%, respectively. The results of small angle X-ray scattering indicate poly(benzoxazole-imide) and poly(benzimidazole-imide) films show periodical lamellar structures, while poly(pyrimidine-imide) shows no long period due to low crystallinity. In-plane orientation (P200) is calculated from polarized attenuated total reflection (ATR)-Fourier transform infrared and refractive indices. The order of in-plane orientation is poly(benzimidazole-imide) < poly(benzoxazole-imide) < poly(pyrimidine-imide). Hydrogen bonding interactions, which restrict chain motion and hinder spontaneous in-plane orientation, are only formed in poly(benzimidazole-imide). The relationship between mechanical properties and three influence factors are discussed, and the order of influence extent for mechanical properties of PI films is hydrogen bonding interactions < degree of crystallization < in-plane orientation. Two structure models for PI films are proposed in order to further confirm the dominant effect of in-plane orientation on the mechanical properties. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44000.