Poly(lactic acid)/poly(vinyl butyral) composites containing kaolin modified by acids and calcination

Abstract The compatibility between two distinct polymers in the blend is important to maximize various properties of the blends. This study investigated the effects of kaolin modifications through acid and calcination treatments on the compatibility, molecular weight, its distribution, and various properties of poly(lactic acid) (PLA)/poly(vinyl butyral) (PVB) blends. In addition, the incorporation of the modified kaolin as a compatibilizer into the blends enhanced their mechanical and thermal properties, addressing the challenges of immiscibility between distinct polymers. The experimental approach included the utilization of scanning electron microscopy, gel permeation chromatography, differential scanning calorimetry, x‐ray diffraction, Fourier transform infrared spectroscopy, rheometer, and melt flow index to examine the structural, molecular, and thermal, mechanical and rheological behaviors of the composites. The changes in various molecular weights were correlated with other properties. The incorporation of surface‐treated kaolin into the blend improved the compatibility between PLA and PVB, exhibiting a singular melting temperature peak and a less distinct interface between two different polymers. This research contributed to the development of sustainable material solutions by demonstrating the potential of modified inorganic fillers in improving the performance of biodegradable polymer blends.