Crystallization Kinetics of Maleated Polypropylene/Clay Hybrids
Crystallization Kinetics of Maleated Polypropylene/Clay Hybrids
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DOI：
10.1021/ie049825y
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发表时间：
2004-08
影响因子：
4.2
通讯作者：
Bae-Hwan Kim;Seung‐Heon Lee;Daewon Lee;Bongwoo Ha;J. Park;K. Char
中科院分区：
文献类型：
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作者：
Bae-Hwan Kim;Seung‐Heon Lee;Daewon Lee;Bongwoo Ha;J. Park;K. Char
采用时间分辨广角X射线散射（WAXS）和差示扫描量热法（DSC）研究了马来酸酐接枝聚丙烯（mPP）与未改性或有机改性蒙脱土（MMT）的混合物的等温结晶动力学。WAXS和透射电子显微镜（TEM）表明，mPP/未改性的MMT杂化物形成宏观相分离的混合物，而不是插层的纳米复合材料，而mPP/有机层状硅酸盐（OLS）杂化物形成剥离的纳米复合材料。mPP/未改性的硅酸盐杂化物的结晶速率变得更快的MMT除了，因为团聚的硅酸盐在mPP基体中作为成核剂。另一方面，随着OLS的加入，mPP/OLS杂化物的结晶速率减慢。这种mPP结晶的延迟可能是由于存在分散良好的片状硅酸盐作为扩散或置换基底。
The isothermal crystallization kinetics of maleic anhydride grafted polypropylene (mPP) in hybrids with unmodified or organically modified montmorillonite (MMT), which have been prepared by melt intercalation in a mixer, has been investigated by using time-resolved wide-angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC). WAXS and transmission electron microscopy (TEM) showed that the mPP/unmodified MMT hybrids formed macrophase-separated mixtures rather than intercalated nanocomposites, while mPP/organically layered silicate (OLS) hybrids formed exfoliated nanocomposites. The crystallization rate of mPP/unmodified silicate hybrids became faster with the MMT addition because agglomerated silicates in the mPP matrix act as nucleating agents. On the other hand, the crystallization rate of the mPP/OLS hybrids was slowed with the OLS addition. This retardation of the mPP crystallization is probably due to the presence of well-dispersed exfoliated silicates as diffusion or displacement ba...