Influence of Interfacial Enantiomeric Grafting on Melt Rheology and Crystallization of Polylactide/Cellulose Nanocrystals Composites  

作　　者：Hua-Gao Fang Kang-Jie Yang Qi-Zheng Xie Xu Chen Sheng-Li Wu Yun-Sheng Ding 

机构地区：[1]Department of Polymer Science and Engineering,School of Chemistry and Chemical Engineering,Hefei University of Technology,Hefei 230009,China [2]Anhui Province Key Laboratory of Advanced Functional Materials and Devices,Hefei 230009,China [3]Anhui Institute for Food and Drug Control,Hefei230051,China

出　　处：《Chinese Journal of Polymer Science》2022年第1期93-106,共14页高分子科学（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(Nos.51503055 and 51673056);the Fundamental Research Funds for the Central Universities(No.PA2020GDKC0009)。

摘　　要：Incorporating the surface-grafted cellulose nanocrystals(CNCs)with enantiomeric polylactide(PLLA or PDLA)is an effective and sustainable way to modify PLLA,but their difference in promoting matrix crystallization is still unrevealed.In this study,the CNCs with identical content and length of PLLA and PDLA(CNC-g-L and CNC-g-D)were prepared and blended with PLLA.The rheological properties of PLLA/CNC-gD are greatly improved,indicating that the stereocomplexation can significantly improve the interfacial strength as compared with the conventional van der Waals force in PLLA/CNC-g-L.Surprisingly,the matrix crystallizes at a higher rate in PLLA/CNC-g-L than PLLA/CNC-g-D.PLLA/CNC-g-L15 reaches its half crystallinity in 8.26 min while a longer period of 13.41 min is required for PLLA/CNC-g-D15.POM observation reveals that the superior crystallization behavior in PLLA/CNC-g-L is originated from its higher nucleation efficiency and faster growth rate.The formation of low content of sc-PLA at the interface can restrict the diffusion of PLLA but contribute less to generate crystalline nuclei,which synergistically leads to the retarded crystallization kinetics in PLLA/CNC-g-D.Revealing the mechanism of different interfacial enantiomeric grafting on the melt rheology and crystallization of PLLA is of great significance for the development of high-performance polylactide materials.

关 键 词：Cellulose nanocrystal Polylactide nanocomposite Interfacial stereocomplexation CRYSTALLIZATION RHEOLOGY 

分 类 号：TB332[一般工业技术—材料科学与工程]