title: Effect of polymorphs of cellulose nanocrystal on the thermal properties of poly(lactic acid)/cellulose nanocrystal composites.
abstract: Cellulose nanocrystals (CNCs) with different polymorphs CNC I and II were fabricated from native and mercerized microcrystalline cellulose (MCC) by sulfuric acid hydrolysis. CNC I and II were successfully acetylated by a "green" method, which was performed in an ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4). X-ray diffraction (XRD) proved that the crystal structure of CNC I and II was maintained after acetylation. Transmission electron microscopy (TEM) showed the rod-like structure for acetylated CNC I and spherical crystal morphologies for acetylated CNC II. Thermogravimetric analysis (TGA) revealed that the thermal stability of CNC I and II was enhanced after acetylation. The effect of CNC polymorphs on the crystallization behavior and thermal stability of poly(lactic acid)/acetylated CNC (PLA/ACN) composites was investigated by differential scanning calorimetry (DSC) and TGA, respectively. It was found that compared to ACN I, ACN II was better able to promote the cold crystallization of PLA-based composites, and PLA/ ACN II possessed higher thermal stability.
authors.affiliation: School of Materials Science and Engineering, Shijiazhuang Tiedao University, 050043, Shijiazhuang, China. zhaojc@stdu.edu.cn.
authors.forename: Junchai
authors.initials: J
authors.lastname: Zhao
authors.affiliation: School of Materials Science and Engineering, Shijiazhuang Tiedao University, 050043, Shijiazhuang, China.
authors.forename: Yujing
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: School of Materials Science and Engineering, Shijiazhuang Tiedao University, 050043, Shijiazhuang, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Materials Science and Engineering, Shijiazhuang Tiedao University, 050043, Shijiazhuang, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Peng
mesh_terms: D000107:Acetylation; D002152:Calorimetry, Differential Scanning; D002482:Cellulose / Q000737:chemistry* / Q000648:ultrastructure; D003460:Crystallization; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D011091:Polyesters / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D013818:Thermogravimetry
chemical_list: C419324:1-butyl-3-methylimidazolium tetrafluoroborate; D007093:Imidazoles; D052578:Ionic Liquids; D011091:Polyesters; C033616:poly(lactide); D002482:Cellulose
keywords: Soft Matter: Polymers and Polyelectrolytes