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Updated: Jan 30, 2026

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超声波辅助挤出加工,通过流动诱导结晶来增强高密度聚乙烯的物理性能
Mansoureh Jamalzadeh1, David O Kazmer1, Patrick Casey1
1Plastics Engineering Department, University of Massachusetts Lowell, Lowell, Massachusetts 01854, United States.
概括
聚合物融中的超声波剪切增强了流动诱导的结晶性,改善了高级包装应用的高密度聚乙烯薄膜的机械和气体屏障性能.
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
- 类风病学 类风病学 类风病学
背景情况:
- 流动诱导的结晶显著影响半结晶聚合物的特性.
- 了解剪切对炼加工的影响对于材料增强至关重要.
- 目前的包装通常依赖于多层结构来获得所需的特性.
研究的目的:
- 在聚合物融流中使用超声波场研究剪切诱导结晶.
- 探索超声波辅助挤出高密度聚乙烯 (HDPE) 薄膜的潜力.
- 开发具有增强性能的单材料薄膜,以取代多层包装.
主要方法:
- 使用定制的超声波模具来控制和温度在融流程.
- 应用常规和超声波切割速率到HDPE化物.
- 使用广角和小角X射线散射 (WAXS/SAXS),拉力测试和氧传导率 (OTR) 分析了聚合物结构和特性.
主要成果:
- 超声波切割速率显著影响了叶片间距和无形分数再分配.
- 传统和超声波切割影响了晶体域结构.
- 处理条件与机械和气体屏障性能直接相关.
结论:
- 超声波辅助加工可以加快晶度,并操纵HDPE薄膜的形态.
- 增强的结晶性导致更好的机械和气体屏障性能.
- 这项技术为包装中的单材料薄膜提供了潜力,减少了对复杂多层结构的依赖.
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