在不同温度下制备的聚合物薄膜之间的接形成:从分子动力学模拟的见解
Mauro L Mugnai1, Jonathan E Seppala2, Peter D Olmsted1,3
1Institute for Soft Matter Synthesis and Metrology, Georgetown University, Washington, D.C. 20057, United States.
Macromolecules
|March 2, 2026
概括
分子动力学 (MD) 模拟显示,聚合物接发生在三个阶段:接触,调整和相互扩散. 热放松显著影响接强度,特别是在孤立的系统.
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
- 计算化学计算化学
背景情况:
- 化纤维制造 (FFF) 增材制造 (AM) 依赖于成功的聚合物接.
- 了解聚合物接形成的基本机制对于优化AM工艺至关重要.
研究的目的:
- 用分子动力学 (MD) 模拟来研究聚合物接形成的早期阶段.
- 分析初始温度差异对接过程和接强度的影响.
主要方法:
- 用分子动力学 (MD) 模拟来建模两个聚合物薄膜之间的相互作用.
- 模拟考虑了在玻璃过渡温度以上和以下的温度下制备的薄膜.
- 分析重点是表面相互作用,热传递和聚合物间扩散.
主要成果:
- 接通过三个不同的阶段进行:表面接近,表面调整和相互扩散.
- 最初的温度差异影响了界面温度和聚合物形状.
- 在接触时发生不对称的热传递;环境热交换在相互扩散之前减轻了温度效应.
- 隔离系统显示,当薄膜具有不同的初始温度时,相互扩散的开始较早.
结论:
- 跨界面的热放松对于聚合物接形成至关重要.
- 在接过程中控制热条件可以提高接强度.
- 模拟MD提供了宝贵的见解,有关AM的聚合物接机制.
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