聚(苯乙烯-b-异丁烯-b-苯乙烯)三嵌段共聚物的合成、表征以及表面形貌研究

摘要

以DiCumCl/TiCl4//DtBP为引发体系,正己烷和一氯甲烷为溶剂,在-80℃下,通过可控正离子聚合法成功合成聚(苯乙烯-b-异丁烯-b-苯乙烯)(SIBS)三嵌段共聚物.通过体积排斥色谱法/示差折光指数/多角激光光散射/紫外分光光度仪(SEC/RI/LS/UV)、热失重分析(TG)、差示量热扫描仪分析(DSC)和原子力显微镜(AFM)对产物进行表征.实验结果表明:SIBS三嵌段共聚物的相对分子质量随着苯乙烯投料量的增加不断提高,聚苯乙烯质量分数也增加,相对分子质量分布没有明显变化.SIBS的DSC测试发现明显的2个Tg(玻璃化转变温度),表明存在微相分离结构.通过AFM对SIBS表观形貌的研究,进一步表明SIBS存在微观相分离结构,退火后相分离结构更有序和更规整.%The synthesis of well-defined poly(styrene-b-isobutylene-b-styrene) (SIBS) triblock copolymers were accomplished by cationic sequential block copolymerization of isobutylene (IB) with styrene (St) with l,4-di(2-chloro-2-propyl)benzene (DiCumCl)/TiCl4/2, 6-di-tert-butylpyridine (DtBP) as initiating system in methyl chloride (CH3Cl)/cyclohexane (Chx) (50/50v/v) solvent mixture at -80 ℃. The SIBS triblock copolymers were characterized by SEC/RI/LS/UV, TG, DSC and AFM. The experimental results show that both the relative molecular mass of SIBS triblock copolymers and the content of PS increase with the increase of the styrene feed. DSC of the SIBS triblock copolymers indicates the microphases separation. AFM further verifies that SIBS shows microphases separation. After annealing, microphases separation structure was translated to more ordered structures.