可溶性聚酰亚胺的制备及其在液晶显示器上的潜在应用

以3,5-二硝基苯甲酰氯和4-羟基联苯为原料,合成了功能性二胺单体3,5-二氨基苯甲酸联苯酯(DABBE).用此单体与3,3′-二甲基-4,4′-二氨基二苯甲烷(DMMDA)、3,3′,4,4′-二苯醚四甲酸二酐(ODPA)共缩聚,采用低温缩聚-化学亚胺化的方法,通过调节共聚物组成制备了5种聚酰亚胺(PI).利用FT-IR、NMR、UV-Vis与DSC等手段对合成二胺单体及聚酰亚胺进行了结构表征和性能测试;研究了其溶解性能、透光性能、取向性能和耐热性能.结果表明,5种聚酰亚胺均可溶于NMP、DMF等极性溶剂;对液晶分子取向时的预倾角随DABBE的比例增加而增大,可达1.8°.但当DABBE的比例增加时,PI的分子量降低,将影响其成膜性能.此外,实验所得的PI透过率大于80%,玻璃化转变温度在220℃以上.     

基于3,5-二胺基-N（N′,N′-正二丁基甲酰胺基苯基）-苯甲酰胺的聚酰亚胺的溶解性、热稳定性和取向性能

用制得的大体积双侧基3,5-二胺基-N（N′,N′-正二丁基甲酰胺基苯基）-苯甲酰胺（DAPDM）,与3,3′-二甲基-4,4′-二氨基二苯甲烷（DMMDA）、3,3′,4,4′-二苯醚四甲酸二酐（ODPA）采用一步法共缩聚制得聚酰亚胺共聚物。采用核磁共振对该共聚物进行了表征,对其溶解性、热稳定性、预倾角进行了分析。结...     

聚合物太阳能电池研究进展

有机材料是近年来新型太阳能电池的研究热点,本文按太阳能电池材料的组成分类,对太阳能电池的原理及其材料的种类进行了详细地总结,重点介绍了导电聚合物基的太阳能电池的研究进展.     

侧链含邻苯二甲酰亚胺的聚酰亚胺液晶垂直取向剂的制备与表征

以邻苯二甲酰亚胺和溴代正辛烷为原料,合成了功能性二胺单体N-辛基-4(3,5-二氨基苯甲酰基)-氨基邻苯二甲酰亚胺(D8).用此单体与3,3’-二甲基-4,4’-二氨基二苯甲烷(DMMDA)、3,3’,4,4’-二苯醚四甲酸二酐(ODPA)共缩聚,采用低温缩聚-化学亚胺化方法,通过调节共聚物组成制备了5种聚酰亚胺(PI).利用FTIR、NMR、UV-Vis与DSC等手段对合成的二胺单体及聚酰亚胺进行了结构表征和性能测试;研究了其摩擦取向性能、透光性能、溶解性能和耐热性能.结果表明,5种聚酰亚胺均可溶于常见极性溶剂,如NMP、THF等;随着D8含量的增加,PI膜对液晶分子取向时的预倾角逐渐增大至垂直,当D8含量大于20%,且经过5次摩擦后,预倾角仍能保持在89°以上.此外实验所得PI透过率大于80%,玻璃化转变温度在260℃以上.     

Effects of Side Chains with Similar Lengths and Different Structures of Polyimides on Liquid Crystal Alignment Behavior

Polyimides（PI） with different side chains in structure were synthesized by copolycondensation of pyromelliticmdianhydride（PMDA） with 3,5-diamino-（4＇-methane acid hexyl ester） phenyl-benzamide（C6-PDA）,（4-butoxybiphenol）-3＇, 5＇-diaminobenzoate（C4-BBDA） and 3, 5-diamino-benzoic acid decyl ester（C10-DA） named PI-PDA, PI-C4, PI-DA, respectively. The lengths of side chains of PI-PDA and PI-DA are as similar as that of PI-C4. Through the pretilt angle tests it is demonstrated that neither the structure of side chains nor the rubbing process could make an obvious difference on vertical alignment property when the lengths of the side chains are similar, standing at around 1.6 nm. The measurement of surface energy of PI surfaces further proved this result. The result of the X-ray photo-electron spectroscope measurement indicated that the side chains of PIs stretched out from the polymer bulk phase and accumulated on the surface.     

多官能Iniferter制备聚合物分散液晶膜及其含量对电光性能的影响

采用可逆加成-断裂链转移(RAFT)、引发转移终止(Iniferter)活性自由基聚合法分步骤制备多官能Iniferter的大分子(RAFT-MI),并通过紫外光聚合诱导相分离法制备接枝共聚物为基体的聚合物分散液晶(PDLC)膜,研究了不同含量的RAFT-MI对PDLC膜的微观形貌、开态透光率、阈值电压(Vth)、饱和电压(Vsat)、对比度和记忆效应的影响.结果表明,当PDLC中的RAFT-MI含量从10%增加到30%时,开态透光率先增加,随后又逐渐降低,而Vth、Vsat逐渐降低,对比度先增加,然后又降低,记忆效应减弱.     

大分子引发剂分子量对接枝聚合物基体的PDLC电光性能的影响

以可逆加成-断裂链转移(RAFT)、引发转移终止(iniferter)活性自由基聚合相结合的方法,用一步法制备了不同分子量的大分子引发剂RAFT-PS-co-PCMSI(MI),并通过紫外光聚合诱导相分离法制备了以接枝聚合物为基体的聚合物分散液晶(PDLC)膜.研究了不同分子量的MI对PDLC的微观形貌,关闭状态透光率,阈值电压,饱和电压以及记忆效应等方面的影响.研究表明,降低PDLC中MI的分子量,会使得液晶微滴粒径增大,阈值电压(Vth)、饱和电压(Vsat)减小,记忆效应、关闭状态透光率升高.     

RHEOLOGICAL BEHAVIOR OF POLYPHENYLENE SULFIDE/POLYAMIDE-66 BLENDS

Blends of polyphenylene sulfide (PPS) containing trace amounts of branching and/orcross-linking in chain and Polyamide-66(PA-66) have been prepared by melt blending. Therheological behavior of PPS/PA-66 blends has been studied by means of capillary rheo-meter, and compared with PPS. The effects of shear rate, shear stress and temperature onthe flow of PPS/PA-66 blends and PPS are discussed. The non-Newtonian indexes andthe activation energies of viscous flow are obtained. The results show that the apparentviscosity of PPS/PA-66 blends is not sensitive to shear rate and stress, but decreases withthe elevation of temperature. On the contrary, the apparent viscosity of the PPS decreasesobviously with the increasing of shear rate and shear stress, but it is increased by theelevation of temperatue.