统计型聚乙烯对高密度聚乙烯的热力学性能的影响
Mohamed H Darweesh1, Bernhard Stoll2, Safaa H El-Taweel3
1Engineering and Materials Science Department, German University in Cairo, New Cairo City, Egypt.
Scientific reports
|November 8, 2024
概括
这项研究研究了高密度聚乙烯 (HDPE) 和聚乙烯-联合乙烯 (VM) 的混合物. 混合改善了混合性和改变了机械性能,低VM含量增强了破裂时的延伸.
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:
- 高密度聚乙烯 (HDPE) 是一种广泛使用的热塑性塑料.
- 聚propylene-co-ethylene (VM) 是一种具有可调节性质的共聚物.
- 了解聚合物混合物的行为对于开发新材料至关重要.
研究的目的:
- 系统地研究HDPE/VM混合物的特性.
- 为了确定HDPE和VM的混合性和兼容性.
- 评估VM含量对HDPE机械和热性能的影响.
主要方法:
- 风病学测量以评估融流动行为.
- 差分扫描热量计 (DSC) 用于热分析.
- 极化光学显微镜 (POM) 用于形态研究.
- 拉力测试用于评估机械强度和柔性.
主要成果:
- 添加VM降低了融粘度,储存和损失模量.
- HDPE和VM在化状态下显示出20-60%的VM含量之间的混合性.
- VM在HDPE结晶上表现出轻微的核化效应.
- 拉力测试显示,随着VM含量的增加,延伸模和屈服应力下降.
- 含有<20%VM的混合物显示在断裂时增强的延长和细小的HDPE球状物.
结论:
- 在特定的组成范围内,HDPE和VM在化状态下可混合.
- VM的结合改变了HDPE的气质和机械性能.
- 该研究为潜在的应用提供了HDPE/VM混合物的结构-属性关系的见解.
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