Crystal morphology of polyurea on rapid quenching
Crystal morphology of polyurea on rapid quenching
复制标题
聚脲快速淬火时的晶体形貌
DOI：
10.1016/j.polymer.2020.123201
复制
发表时间：
2021
期刊：
影响因子：
4.6
通讯作者：
Hu Wenbing
中科院分区：
文献类型：
--
作者：
Chonan Yuta;Matsuba Go;Nishida Koji;Hu Wenbing
脂肪族聚脲（普阿）是一种很有前途的生物工程塑料，可以由天然资源蓖麻油和二氧化碳制备。因此，普阿生产可用于螯合二氧化碳，同时生产环境友好的塑料。然而，普阿的结晶行为仍然是未知的。本文对普阿的结晶行为进行了详细的分析。最初，在从熔体快速淬火时，δ-形式的生长结晶。此外，100纳米尺度的密度波动和晶体生长过程中观察退火。密度起伏可归因于结核型结构。从熔体中结晶后的三个熔点，通过闪光差示扫描量热法测量观察。这三个熔融峰被分配到熔化的普阿结节，温度依赖的晶体增厚，和熔化的再结晶晶体从结节型结构。
Aliphatic polyurea (PUA) is a promising bioengineering plastic that can be prepared from natural resources: castor oil and carbon dioxide. Thus, PUA production could be used to sequester carbon dioxide while producing an environmentally friendly plastic. However, the crystallization behavior of PUA remains unknown. Herein, we reported the detailed analyses of crystallization behavior of PUA. Initially, upon rapid quenching from the melt, the growth of the δ-form crystallizes. Further, 100-nm scaled density fluctuations and the crystal growth process were observed during annealing. The density fluctuations can be assigned to a nodule-type structure. Three melting points after crystallization from the melt were observed by flash differential scanning calorimetry measurements. These three melting peaks were assigned to the melting of PUA nodules, temperature-dependent crystal thickening, and melting of recrystallization crystals from the nodule-type structure.