选择性表面相互作用对聚合物相位分离的影响,在聚合过程中具有明确的聚分散性.
Hyeonmin Jeong1, Junsi Gu2, Paul Mwasame2
1Department of Chemical and Biomolecular Engineering, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA. cesing@illinois.edu.
Soft matter
|January 21, 2025
概括
表面相互作用在聚合过程中加速聚合物混合物的早期分离. 这项研究模拟了聚合分散性和表面对聚合物形态的潜在影响,揭示了基于聚合率的独特排序行为.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 聚合物-基板相互作用显著影响相位分离动力学和最终材料特性.
- 表面可以作为相位分离的额外驱动力,并与聚合.
研究的目的:
- 模拟聚合物混合物中相位分离在表面附近经过聚合.
- 调查表面电位和聚合率对形态学和异型排序的影响.
主要方法:
- 修改聚合Cahn-Hilliard (pCH) 方法以包括一个表面电位.
- 通过考虑不同的分子重量组件,显式建模多分散性.
- 模拟一种具有物种选择性表面潜力的二元聚合物混合物.
主要成果:
- 表面潜能在早期加速较小分子的相位分离.
- 在较低的聚合率下,较小的分子在表面积聚,从而促进了更重的聚合物生产.
- 在高的聚合率下,散装积累先于表面启动的异构相分离.
结论:
- 表面潜力在控制早期阶段分离和表面附近的聚合物分布方面发挥着至关重要的作用.
- 聚合率和表面相互作用强度决定了聚合物混合物中异性排序的程度.
- 开发的模型为设计具有特定形态和特性的聚合物材料提供了洞察力.
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