Preparation of AKD‐coupled mica and research on the modification to poly(butylene adipate‐co‐terephthalate)/poly(propylene carbonate) composite films

Mica is a variety of filler material with excellent barrier properties. In the present study, mica-AKD was successfully prepared by treating sericite mica surface with alkyl ketene dimer (AKD). The distribution and content of AKD in mica, the mode of its binding with mica and its surface properties were characterized by thermogravimetry, Soxhlet extraction, Fourier infrared analysis, the scanning electron microscope with energy spectrum and contact angle analysis. The results show that AKD was combined with mica through physical adsorption and chemical grafting, with the content of AKD in mica-AKD exceeding 5 wt%. Due to AKD-coated mica surface, mica-AKD showed hydrophobicity. PCM and PCMa films were prepared by blending PBAT and PPC with mica and mica-AKD, respectively. Given the same content, mica-AKD has better compatibility with PBAT/PPC matrix, and PCMa films show better mechanical properties, lower water vapor permeability and oxygen permeability, and higher CDTR/OTR ratio, which has a good application prospect in fruit and vegetable preservation materials.