超高分子量聚乙烯的特征和风病学特性
Alexander Ya Malkin1, Tatyana A Ladygina2, Sergey S Gusarov2
1A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29, Leninskiy Prospect, 119991 Moscow, Russia.
Polymers
|January 8, 2025
概括
研究超高分子量聚乙烯 (UHMWPE) 发现分子量和质性质取决于方法. 在高温下,UHMWPE表现出弹性-塑性行为,而不是粘性流,随着时间的推移而发生降解.
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:
- 超高分子量聚乙烯 (UHMWPE) 是各种应用中的关键材料.
- 了解其分子特征和质性质对于加工和性能至关重要.
- 由于校准和溶解依赖,现有的表征方法可能会产生不一致的结果.
研究的目的:
- 调查三个UHMWPE样本的分子特征和质性质.
- 评估不同表征方法对分子量确定的影响.
- 了解UHMWPE的高温行为和流量特性.
主要方法:
- 高温凝浸透色谱 (GPC) 用于分子量分布 (MWD) 和平均分子量 (MW) 分析.
- 使用聚钢 (PS) 标准与线性和立体近似,以及线性聚乙烯 (PE) 数据进行校准.
- 在各种剪切应力和温度下 (高达210°C) 使用爬行和振荡测试测量风湿性质.
主要成果:
- 分子重量评估高度依赖于校准方法和溶解时间,立方PS近似值产生制造商一致的结果.
- 在210°C时,UHMWPE表现出弹性-塑性行为,不可逆转的变形归因于可塑性而不是流动性.
- 最终的塑性变形随着分子量增加而减少,长时间暴露在高温下会导致大分子降解,而不是粘性流.
结论:
- 准确地描述UHMWPE需要仔细选择GPC校准方法,并考虑溶解效应.
- 即使在高温下,UHMWPE也不能达到终端粘性流域;它表现为弹性-塑料材料.
- 高分子量和加工条件显著影响HMWPE的机械反应和稳定性,降解是关键问题.
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