聚烯混合物与选择性交联分散相混合,基于西兰基改性聚乙烯
Markus Gahleitner1, Tung Pham2, Doris Machl1
1Borealis Polyolefine GmbH, Innovation Headquarters, St. Peterstr. 25, 4021 Linz, Austria.
Polymers
|December 23, 2023
概括
这项研究探讨了使用西兰-交联聚乙烯 (PE) 修饰剂来增强聚烯 (PP) 的冲击强度. 较低密度的PE修饰剂,特别是含有烯酸盐的修饰剂,显著提高了性,尽管相位稳定不是主要的机制.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料科学 材料科学 材料科学
- 复合材料 复合材料 复合材料
背景情况:
- 聚烯 (PP) 多相组合物需要形态稳定,以保持一致的冲击强度.
- 现有的稳定PP形态的方法在性能和适用性方面存在局限性.
- 分离混合和交联过程为材料改造提供了一种新的方法.
研究的目的:
- 调查使用西兰交联聚乙烯 (PE) 同型和共聚合物作为PP的冲击修饰剂.
- 评估不同PE修饰剂对各种PP共聚合物的刚性冲击平衡的影响.
- 了解冲击强度改进背后的机制,并评估可处理性.
主要方法:
- 使用商业用烯共聚合低密度PE (LD-PEX) 和烯接种高密度PE (HD-PEX) 作为修饰剂.
- 与各种PP共聚合物配制的混合物,包括乙烯-随机共聚合物 (PPR),冲击 (PPI) 和随机冲击 (PPRI) 共聚合物.
- 评估了由此产生的组合物的冲击强度,刚度与冲击平衡,形态和融化流量.
主要成果:
- 使用LD-PEX和HD-PEX修饰剂的混合物在PPR,PPI和PPRI共聚合物中显示出更好的刚性影响平衡.
- 较低密度的PE修饰剂,特别是带有烯酸的LD-PEX (Tg ~ -40 °C),表现出优越的硬化效果.
- 观察到冲击强度的改善,但主要不是由于预期的相位稳定;混合过程中颗粒大小增加.
- 热塑性可加工性得到维持,但化流速的下降限制了实际应用.
结论:
- 可交叉链接的PE修饰剂提供了一个可行的途径来增强PP共聚物质的冲击性能.
- 修饰剂密度和特定的共因子 (如烯酸盐) 显著影响固效率.
- 虽然保留了可加工性,但对于工业用途,降低融流速需要仔细考虑.
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