【作者】 周慧琴；

【导师】 刘程；

【作者基本信息】 大连理工大学 ， 化学工程， 2012， 硕士

【摘要】 聚芳醚类聚合物由于具有高模量、强韧性、较高的耐热性、良好的热氧化稳定性和耐化学性等具有优异的物理性质,被认为是一类重要的热塑性工程塑料。本课题组研发出的新型聚芳醚砜酮(PPESK),具有扭曲非共平面结构,既耐高温又可溶解,是目前耐热等级最高的可溶性聚芳醚新品种,但其熔体粘度大,熔融加工性差,常规的注射挤出加工困难。本文从分子结构设计出发,以酚氧盐封端的PPESK齐聚物和联苯二酚(BP)酚氧盐及4,4’-二氟二苯甲酮(DFK)为原料,通过亲核取代的方法合成PPESK-b-PEBEK嵌段共聚物以改善PPESK的加工性能。设计PPESK齐聚物的数均分子量为10800,PEBEK齐聚物的分子量为3000。经过热性能测试结果表明：采用分步加料法(先加BP酚氧盐的方法)合成嵌段共聚物PPESK-b-PEBEK.合成了含不同PEBEK含量的PPESK5050(S：K=1：1)体系和PPESK8020(S:K=8:2)体系的两大系列嵌段共聚物,即PPESK5050-b-PEBEK和PPESK8020-b-PEBEK。研究结果表明：常温下,在PEBEK含量分别低于15%和20%时,PPESK5050-b-PEBEK可分别溶于氯仿和四氯乙烷中,在PEBEK含量低于25%时,PPESK8020-b-PEBEK可溶于四氯乙烷中；由红外谱图可知,-NH封端的PPESK齐聚物与PEBEK发生了进一步的反应；粘度测试结果表明,随着PEBEK链段含量的增加,共聚物的特性粘度越来越小；由DSC扫描结果可知,两种共聚物的Tg在260℃附近,Tm在330℃附近,随着PEBEK链段含量的增加,其玻璃化转变温度降低,熔点Tm无变化；TGA测试结果说明,5%热失重温度在500℃附近变化,10%热失重在520℃左右变化,嵌段共聚物的热稳定性没有显著变化；WAXD测试结果表明,嵌段共聚物PPESK-b-PEBEK表现了PEBEK的结晶性能；通过DMA测试表明,PPESK-b-PEBEK的储能模量为2.5GPa；通过哈克流变测试可知,与PPESK相比,PPESK-b-PEBEK的熔融粘度明显下降了,即PEBEK的引入改善了PPESK的流变性能。更多还原

【Abstract】 Poly(aryl ether)s are considered as an important class of high performance engineering thermoplatsics due to their excellent physical properties such as high modulus, toughness, high thermal, thermo oxidative stability and chemical resistance. Novel poly(phthalazinone ether sulfone ketone)s (PPESK) synthesized by our group, are a heat resistant poly(aryl ether)s with reasonable solubity containing phthalazinone moiety. However, their high melting viscosity make them hard to process by extruding molding and injection molding.In order to improve the melting processing of PPESK, PPESK-b-PEBEK is successfully synthesized via PPESK oligmer endcapped by phenoxide and PEBEK segment drived from the reaction of biphenyoxide and bis(4-fluorophenyl) ketone. The number-average molecular weight(Mn) of PPESK oligmer is10800and Mn of PEBEK oligmer is3000. Three synthetic routes were investigated. The results in DSC showed that addition of BP first into the reaction system named as step-by-step is selected to synthesize this kind of block copolymers.PPESK-b-PEBEKs were synthesized with different weight contents of PEBEK in PPESK5050series and PPESK8020series respectively. The copolymers obtained with PEBEK segments below to20wt%for PPESK5050-b-PEBEK and below to25wt%for PPESK8020-b-PEBEK, respectively, could be soluble in tetrachloroethane. According to the FTIR spectram, the reaction of PPESK oligmer with-NH chain-ends and PEBEK with the fluorine chain-ends took place. Viscosity measuring of PPESK-b-PEBEK showed that the inherent viscosity of block copolymer decreased with increasing content of PEBEK. PPESK-b-PEBEKs exhibited glass transition temperatures ranging from230℃to280℃and melting temperature around330℃in DSC. Tg increased with the raising content of PEBEK. There was no obvious change of Tm. These block copolymers showed very high thermal stability up to500℃around for5%weight loss and520℃around for10%weight loss under nitrogen in TGA. The crystal peaks of PEBEK in the copolymers were observed in WAXD. DMA results exhibit that the storage modulus of PPESK-b-PEBEK in PPESK8020series is2.5GPa. The HAKKE rheological property tests proved that PPESK-b-PEBEK led to a marked decrease in melt viscosities compared with PPESK indicating that the rheological behaviour of PPESK is improve with the addition of PEBEK.更多还原