Investigation of crystallization behavior of asymmetric PLLA/PDLA blend using Raman Imaging measurement
Investigation of crystallization behavior of asymmetric PLLA/PDLA blend using Raman Imaging measurement
复制标题
使用拉曼成像测量研究不对称 PLLA/PDLA 共混物的结晶行为
DOI：
10.1016/j.polymer.2019.03.049
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发表时间：
2019-05-20
期刊：
影响因子：
4.6
通讯作者：
Zhang, Jianming
中科院分区：
文献类型：
--
作者：
Hu, Jian;Wang, Jiping;Zhang, Jianming
采用原位时间分辨FTIR和拉曼成像技术研究了不对称PLLA/PDLA共混物（4/1）在100 ℃左右的等温结晶行为。FTIR结果表明，在等温过程中，由于形成了大量的立体络合物（SC），阻碍了均晶（HC）的结晶。通过偏光显微镜（POM）观察到一种独特的球晶形貌，并借助拉曼成像测量揭示了SC和HC在大球晶内外的分布。结果表明，SC晶体在非晶区和球晶区均分散均匀。而HC主要分布在大球晶区。提出了PLLA/PDLA不对称共混物的等温结晶过程。
In the present study, isothermal crystallization of asymmetric PLLA/PDLA blend (4/1) at around 100 degrees C was investigated by in-situ time-resolved FTIR and Raman Imaging measurement. FTIR result indicated that crystallization of homo-crystal (HC) was retarded due to the formation of large amount of stereocomplex (SC) in the isothermal process. A unique spherulite morphology was observed through polarized optical microscopy (POM) and the distribution of SC and HC in and out of the big spherulite was revealed under the assistance of Raman imaging measurement. These results demonstrated that the SC crystal dispersed homogeneously both in the amorphous and spherulite region. However, the HC mainly located in the big spherulite area. A possible isothermal crystallization process for the asymmetric PLLA/PDLA blend was proposed.