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双块共聚物和反应性单聚物的混合物中的反应诱导的形态转变:散射粒子动力学模拟

Yoshinori Tomiyoshi¹, Yutaka Oya², Toshihiro Kawakatsu³

¹Center for Soft Matter Physics, Ochanomizu University, Bunkyo-ku, Tokyo 112-8610, Japan. tomiyoshi.yoshinori@ocha.ac.jp.

|December 6, 2023

概括

散射粒子动力学模拟揭示了共聚物-单聚物混合物的交联反应如何驱动形态过渡. 交叉链接的速度决定了结构是否被保存或转变,从而影响域相关性.

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
计算化学的计算化学

背景情况:

在区块共聚物中微相分离对于先进材料至关重要.
了解反应条件下的形态转变是控制材料性质的关键.
同聚合物-单体混合物为动态形态控制提供了一个平台.

研究的目的:

通过消散粒子动力学 (DPD) 来研究AB-diblock共聚合物与反应性C-单体的形态转换.
阐明交联反应动力学对域形态学和空间相关性的影响.
为了将模拟结果与对形态变化的实验观测相关联.

主要方法:

利用散射粒子动力学 (DPD) 模拟来建模形态变化.
采用密度偏差的蒙特卡洛和自我一致的场理论来准备初始的模拟结构.
在C-单体中引入并改变交联反应速率,以研究它们的影响.

主要成果:

DPD模拟成功地重现了实验观察到的形态过渡.
快速交叉链接保留了圆柱形域,但增加了域间距.
缓慢的交叉链接导致域变形和过渡到较低曲率形态 (例如,圆柱形到状).
交叉连接速度影响了空间相关性,区分了核化生长和旋分解过程.

结论:

交叉连接反应的动力学显著控制了共聚合物-单体系统中微相分离域的形态演变.
域变形和网络形成之间的相互作用决定了最终的形态.
模拟结果为管理形态转换和域相关性的机制提供了洞察力.

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