侧基取代对羟基芴Cardo结构聚酰亚胺性能的影响  

Effect of Side Group Substitution on the Properties of Cardo-Type Polyimides Containing Hydroxyl Groups

作　　者：刘述梅[1] 陈嘉骏 吴彦城 赵建青[1,2] LIU Shumei;CHEN Jiajun;WU Yancheng;ZHAO Jianqing(College of Materials Science and Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China;Guangdong Key Lab of High Property&Functional Polymer Materials,Guanzhou 510640,Guangdong,China)

机构地区：[1]华南理工大学材料科学与工程学院,广东广州510640 [2]广东省高性能与功能高分子材料重点实验室,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2021年第12期16-22,共7页Journal of South China University of Technology(Natural Science Edition)

基　　金：广东省基础与应用基础研究基金资助项目(2019B1515120073);广东省重点领域研发计划项目(2019B010940001)。

摘　　要：以含羟基芴Cardo结构的二胺和双酚A型二酐为基材,通过一步化学亚胺化法制备出羟基芴Cardo结构聚酰亚胺(PI-OH),再通过其侧羟基的酰氧化或硅醚化反应制备出低极性、大体积的丙酰氧侧基芴Cardo结构PI(PI-OA)和叔丁基二甲基硅醚侧基芴Cardo结构PI(PI-OSi),系统研究了侧基取代对PI-OH溶解性、光学性能和介电性能等的影响。结果表明:侧基的极性和体积较大程度影响了PI薄膜的各项性能,相较于PI-OH,PI-OA和PI-OSi表现出更好的溶解性能、更高的透光率和更低的介电常数,二者可溶于二氯甲烷、丙酮等低极性低沸点溶剂,在450 nm的透光率分别高达86.7%和85.2%,介电常数分别低至2.75和2.63(1 MHz);由于低极性、大体积取代基团的引入,PI-OA和PI-OSi的玻璃化转变温度下降、热膨胀系数增大。The cardo-type polyimides containing hydroxyl groups(PI-OH)were synthesized with one-step chemical imidzation method by taking hydroxyl-containing fluorene diamine and 44′-(44′-Isopropylidenediphenoxy)diphthalic anhydride as substrates.Then,cardo-type polyimides with low polarity and bulky size propionyloxy side groups(PI-OA)/tert-butyldimethylsiloxy side groups(PI-OSi)were prepared by acyl oxidation or silyl ether reaction of side hydroxyl groups.The effects of side group substitution on the solubility,optical and dielectric properties,etc.of PI-OH were systematically investigated.The results show that the polarity and size of side groups greatly impacts the performances of PI films.Compared with PI-OH,PI-OA and PI-OSi show better solubility,higher transmittances and lower dielectric constants.Both can dissolve in low polar solvents such as dichloromethane or acetone.Their transmittances at 450 nm can reach 86.7%and 85.2%,their dielectric constants are as low as 2.75 and 2.63(1 MHz).PI-OA and PI-OSi exhibit lower glass transition temperature and higher thermal expansion coefficients due to the introduction of low polarity and bulky size substituent groups.

关 键 词：侧基取代 羟基芴Cardo结构聚酰亚胺 酰氧化 硅醚化反应 溶解性 透光率 介电性能 

分 类 号：O631[理学—高分子化学]