期刊
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
卷 146, 期 5, 页码 2115-2126出版社
SPRINGER
DOI: 10.1007/s10973-020-10446-y
关键词
Isotactic polypropylene (iPP); nano-zinc oxide (nano-ZnO); Heterogeneous nucleation; Self-nucleation; β -crystal
资金
- Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions
Nano-zinc oxide is an efficient beta-nucleating agent for isotactic polypropylene, promoting the formation of beta-crystal with certain concentration; The efficiency of nano-ZnO as a beta-nucleating agent is dependent on its concentration and dispersibility.
The influence of nano-zinc oxide (nano-ZnO) on the crystallization and melting behaviors of isotactic polypropylene (iPP) was investigated by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and polarized optical microscopy (POM). The results indicated that nano-ZnO is an efficient beta-nucleating agent for iPP. The relative content of beta-crystal rises at first and then goes down with increasing nano-ZnO concentration and can reach 95.2% while incorporating 3% nano-ZnO during isothermal crystallization at 132 degrees C. The beta-nucleating efficiency of nano-ZnO depends on its concentration and dispersibility in the iPP matrix. The lattice constants of nano-ZnO are a = b = 0.325 nm and c = 0.521 nm, and 0.325 nm is exactly half of the unit cell parameter in the c-direction of beta-iPP. This lattice matching facilitates the formation of beta-crystal. Moreover, the relationship between heterogeneous nucleation and self-nucleation of iPP with addition of nano-ZnO was also explored by adjusting the fusion temperature T-f. DSC measurements confirmed that the ordered structures of iPP inhibit beta-crystallization induced by nano-ZnO. Meanwhile, the introduction of nano-ZnO also reduces the alpha-nucleating activity of the ordered structures. A possible interaction mechanism was proposed.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据