在triblock共聚物中,结晶和微相分离之间的竞争和合.
Shichu Yang1, Zhihao Shen1, Xing-He Fan1
1Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.
Macromolecular rapid communications
|February 27, 2026
概括
块共聚合物与液晶和半晶块自组装成状和六角结构. 聚合物结晶显著影响纳米结构的形成,导致独特的相位过渡.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 块共聚合物 (BCP) 自组装成各种纳米结构.
- 结合液晶 (LC) 和半晶体聚合物修改了BCP的自组装.
- 半导体外套LC聚合物 (MJLCPs) 具有独特的特性.
研究的目的:
- 合成和描述含有聚甲基素 (PDMS),聚L-乳酸 (PLLA) 和PMVBPLC块的新型BCP.
- 研究PLLA结晶对BCP纳米结构形成的影响.
- 探索温度依赖的相位行为和过渡.
主要方法:
- 三阻抗共聚合物的合成 (PDMS-b-PLLA-b-PMVBP).
- 温度依赖的小角度X射线散射 (SAXS) 用于结构分析.
- 分析相位转换和纳米结构的演变.
主要成果:
- 双块共聚合物PLLA-b-PMVBP由于具有相似的可溶性参数,没有显示有序的纳米结构.
- 在环境温度下,triblock共聚合物PDMS-b-PLLA-b-PMVBP呈现出状 (LAM),在高温下呈现出六角形 (HEX).
- PLLA结晶显著影响了BCP自组装,可能与微相分离竞争或合.
- 观察到一种罕见的下层障碍 - 顺序过渡 (LDOT).
结论:
- 聚合物结晶和微相分离之间的相互作用支配了BCP纳米结构.
- 观察到温度诱导的结构转变 (LAM到HEX).
- 包括LDOT在内的新阶段行为突出显示了使用功能块自组装BCP的复杂性.
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