粉碎改性的修改和老化机制 基于分子动力学模拟的改性
1School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China.
Materials (Basel, Switzerland)
|January 11, 2025
概括
在青改造中的碎 (CR) 通过减少组件移动来改善机械性能. 老化显著恶化了青-的兼容性和机械性能,为CR改性青再生提供了洞察力.
科学领域:
- 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.
- 环境科学 环境科学
背景情况:
- 从废旧轮胎中使用碎 (CR) 来修改青提供了环境效益和实际价值.
- 对于CR与青的精确纳米修饰机制仍然不完全理解.
- 研究CR改性青 (CRMA) 机制,老化效应和聚合物相互作用至关重要.
研究的目的:
- 为了阐明CR在青中的纳米修饰机制.
- 分析老化对CRMA性能和性能的影响.
- 检查CRMA和常见聚合物之间的界面相互作用.
主要方法:
- 构建和验证基本青,CRMA (原始和老化) 和聚合模型的分子模型.
- 对物理性能 (密度,兼容性,扩散系数) 和机械性能进行系统分析.
- 评估组件相互作用行为和总体界面粘附.
主要成果:
- 电阻降低了青的扩散系数31%,抑制了组件的运动,并提高了机械性能.
- 老化严重降低了青-CR兼容性,显著增加了溶解度参数差异.
- 老化降低了断力和青模块对于青和CRMA.
- 与二氧化 (SiO2) 相比,碳酸 (CaCO3) 与青的粘合力比二氧化 (SiO2) 大22.5%39.9%.
结论:
- 通过限制组件的移动性,CR修改提高了青的机械性能.
- 衰老对CRMA产生负面影响,降低了兼容性和机械强度,突出了再生挑战.
- 聚合物类型影响粘附性,CaCO3的相互作用比SiO2更强,为材料选择提供了数据.
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