用链条延长器升级和增强回收聚乙烯二甲:深入材料特性
Christian W Karl1, Bjørnar Arstad2, Madina Shamsuyeva3
1SINTEF Materials and Nanotechnology, Polymer and Composite Materials Group, P.O. Box 124 Blindern, 0314 Oslo, Norway.
概括
克是一种更有效的化学链延长剂 (CE),用于回收聚乙烯二甲 (PET),而不是甲 (PMDA). 这使得回收PET材料的风质性能得到改善,储存模量更高.
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:
- 回收的低分子量聚乙烯二甲 (PET) 往往需要财产恢复.
- 化学链延长剂 (CE) 用于提高回收聚合物的分子量和性能.
- 来自瓶子和托盘的工业PET废物对回收和再加工提出了独特的挑战.
研究的目的:
- 调查Joncryl和 pyromellitic dianhydride (PMDA) 作为CE对回收PET的影响.
- 评估CE类型和度对质性质,特别是粘度的影响.
- 为了比较Joncryl与PMDA在混合再生PET流中的链延伸的有效性.
主要方法:
- 使用差分扫描热度计,粘度计和圆板体质计进行表征.
- 通过热解气体染色学-质谱学和光谱学 (FTIR,13C SSNMR,1H NMR) 进行高级分析.
- 使用尺寸排除色谱测定分子重量.
主要成果:
- 与PMDA相比,Joncryl在回收PET中显示出更高的链延长效率.
- 用Joncryl扩展的PET样本显示出显著更高的储存模量值.
- 由于水的形成,PMDA的有效性可能受到阻碍,加速了PET的降解.
结论:
- 克是一种更适合的CE,用于增强回收PET的特性,特别是混合流.
- 选择CE显著影响回收PET的质性能和稳定性.
- 了解CE机制对于有效的PET回收和升级至关重要.
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