通过实时SAXS/WAXSS研究的板状半晶块共聚物单晶悬浮体的温度增强排序
Enyi Chi1, Haiying Huang1,2, Fajun Zhang3
1State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China.
Langmuir : the ACS journal of surfaces and colloids
|February 21, 2025
概括
血小板合体中的软相互作用会导致温度敏感的相位过渡. 加热增强了聚乙烯 - 块 - 聚 ((l-乳化物) 块共聚合物单晶的排序,揭示了不同的排序模式和记忆效应.
科学领域:
- 合体和表面科学科学
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
背景情况:
- 硬血小板合体通常由驱动自组成液晶相,表现出低温敏感性.
- 真实的体系统经常表现出柔软的相互作用,导致温度敏感的相位过渡.
- 了解温度依赖的相位行为和软相互作用的影响仍然有限.
研究的目的:
- 为了研究血小板合物与柔软相互作用的温度依赖相位行为.
- 探索软相互作用如何影响温度变化时的相位过渡.
- 在不同的热条件下分析聚乙烯-块-聚-乳酸) 块共聚合物单晶 (BCSC) 的排序动态.
主要方法:
- 利用小和广角X射线散射 (SAXS/WAXS) 和极化光学显微镜 (POM) 来研究BCSCs.
- 在p-xylen中分散的有效直径为500 nm (BCSC500) 和1000 nm (BCSC1000) 的研究BCSC.
- 在加热,火,自我播种和晶体生长周期期间监控订单行为.
主要成果:
- 对于两种BCSC大小,在化前加热过程中观察到增强的排序,特别是面对面的相关性.
- 在BCSC500的105°C时出现了订单,而BCSC1000在内马特阶段显示了增强的订单,直到第九个相关性峰值.
- 冷却导致BCSC500的订单消失,但BCSC1000的持续存在,表明记忆效应.
结论:
- 观察到温度增强的排序现象,归因于侧面相互作用,回火和记忆效应.
- 提出了三种不同的排序制度:大规模的阴性顺序,增强的短距离顺序和短距离集群.
- 软相互作用显著影响温度依赖的相位行为和合体系统的排序.
相关概念视频
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