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纳米纤维核剂和工艺条件对异性聚烯结晶行为和机械性能的影响
Gang Wang1,2, Mengyao Dong1, Xin Pan1
1Key Laboratory of Material Processing and Mold Technology, School of Mechanical Engineering, Chongqing Industry Polytechnic College, Chongqing 401120, China.
Nanomaterials (Basel, Switzerland)
|August 27, 2025
概括
将DMDBS等纳米纤维核化剂添加到异性聚烯 (iPP) 中,可以通过改善结晶来增强机械性能. 这项研究详细介绍了DMDBS含量,化温度和注射速度如何影响IPP.
科学领域:
- 聚合物科学与工程
- 材料科学
- 结晶工程
背景情况:
- 纳米纤维作为核化剂,影响聚合物结晶的动态.
- 调节晶体形态和结构可以提高材料的机械性能.
- 隔离性聚烯 (iPP) 是一种广泛使用的聚合物,其特性可以通过受控的结晶来改善.
研究的目的:
- 研究纳米纤维核化剂1,3,4-二甲基基醇 (DMDBS) 对iPP结晶和机械性能的影响.
- 确定DMDBS含量,化温度和注射速度对iPP结晶行为的影响.
- 阐明DMDBS增强iPP机械性能的机制.
主要方法:
- 对DMDBS含量,化温度和注射速度进行系统调查.
- 使用核和生长动态分析iPP结晶行为.
- 评估机械性能,包括拉伸强度,弹性模量和冲击强度.
- 晶体形态和结构的微观分析.
主要成果:
- 加入DMDBS显著增加了iPP核,减少了晶体大小,并将结晶温度提高了~11°C.
- iPP/DMDBS的拉力强度和弹性模量分别提高了15%和55%.
- 融化温度的提高降低了晶体性和机械性质;注入速度的提高提高了拉伸强度和弹性模量.
结论:
- 通过形成纳米纤维网络,DMDBS作为有效的核化剂降低了iPP核化的能量障碍.
- 由剪切力影响的纳米纤维网络促进了定向的晶体结构,增强了机械性能.
- 化温度和注射速度等处理参数对ipp中的dmdbs的有效性具有重要影响.
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