中国塑料 ›› 2024, Vol. 38 ›› Issue (12): 1-7.DOI: 10.19491/j.issn.1001-9278.2024.12.001

• 材料与性能 •    下一篇

超分子助剂对间规聚苯乙烯构象和结晶行为的调控

沈赢洲, 刘磊, 种锦轩, 张凯(), 尹波()   

  1. 四川大学高分子科学与工程学院,高分子材料工程国家重点实验室,成都 610065
  • 收稿日期:2024-04-11 出版日期:2024-12-26 发布日期:2024-12-25
  • 通讯作者: 张凯,副研究员,主要从事高分子材料微纳结构制备与调控的研究,k.zhang@scu.edu.cn
    尹波,教授,主要从事聚合物共混及复合材料的结构与性能研究,yinbo@scu.edu.cn
    E-mail:k.zhang@scu.edu.cn;yinbo@scu.edu.cn
  • 基金资助:
    四川省科技厅2022年国际科技创新合作项目(2022YFH0085)

Regulation of supramolecular additives on conformation and crystallization behaviors of syndiotactic polystyrene

SHEN Yingzhou, LIU Lei, CHONG Jinxuan, ZHANG Kai(), YIN Bo()   

  1. College of Polymer Science and Engineering,State Key Laboratory of Polymer Materials Engineering,Sichuan University,Chengdu 610065,China
  • Received:2024-04-11 Online:2024-12-26 Published:2024-12-25
  • Contact: ZHANG Kai, YIN Bo E-mail:k.zhang@scu.edu.cn;yinbo@scu.edu.cn

摘要:

通过熔融共混法制备了间规聚苯乙烯(sPS)/N,N'⁃二苯基对苯二甲酰胺(DPHT)复合材料。利用sPS与DPHT之间的π⁃π相互作用,对sPS分子链的构象和结晶行为进行调控。结果表明,DPHT在sPS基体中存在自由分子和自组装体两种状态,DPHT的加入,提高了sPS的全反式构象(TTTT)含量,并在DPHT形成自组装体时达到最大值,且DPHT自组装结构还能有效提高sPS中β晶型的含量;当降温速率较小时(5 ℃/min或2 ℃/min),sPS/DPHT中sPS的β晶占比较α晶多,而当降温速率升高至10 ℃/min时,sPS中α晶含量更多;当DPHT以自由分子状态分散在sPS基体中时,DPHT与sPS之间的相互作用反而限制了sPS的结晶能力(结晶度由41%降低至35.9%);当DPHT处于自组装状态分散在sPS中时,DPHT的自组装体会在sPS结晶过程中作为晶核促进sPS的结晶(结晶度由36.1%提升至38.2%)。因此,基于DPHT与sPS之间的相互作用,成功实现了在熔融加工过程中对于sPS构象和结晶行为的调控。

关键词: 间规聚苯乙烯, 构象, 结晶行为, π?π相互作用

Abstract:

Syndiotactic polystyrene (sPS)/N,N'⁃diphenylterephthalamide (DPHT) blends were prepared through melt blending, and the conformation and crystallization behaviors of sPS were regulated by utilizing the π⁃π interactions between sPS and DPHT. The results indicated that there were two dispersion states for DPHT, i.e., free molecule or as self⁃assemblies, existing in the sPS matrix. The addition of DPHT increased the content of the all⁃trans conformation (TTTT) of sPS and reached a maximum when the self⁃assemblies were formed for DPHT. Moreover, the self⁃assembled structures of DPHT effectively increased the content of β⁃crystals in sPS. The proportion of the β⁃crystals was higher than that of the α⁃crystals in the sPS/DPHT blends at a slow cooling rate of 5 or 2 ℃/min. However, the α⁃crystal content in sPS was higher when the cooling rate was increased to 10 ℃/min. When DPHT was molecularly dispersed in the sPS matrix, the π⁃π interaction between DPHT and sPS restricted the crystallization ability of sPS, resulting in a decrease in the degree of crystallinity from 41 % to 35.9 %). When DPHT was in the self⁃assembly state, the self⁃assemblies of DPHT acted as a nucleating agent to promote the crystallization of sPS, leading to an increase in the degree of crystallinity from 36.1 % to 38.2 %. Therefore, the conformation and crystallization behaviors of sPS were successfully regulated during melt processing through the π⁃π interactions between DPHT and sPS.

Key words: syndiotactic polystyrene, conformation, crystallization behavior, π?π interaction

中图分类号: