Preparation and Characterization of Acetylated Nanocrystalline Cellulose-reinforced Polylactide Highly Regular Porous Films

Nanocrystalline cellulose was prepared from bleached softwood kraft pulp using acid hydrolysis. Acetylated nanocellulose (AcNCC) and polylactic acid (PLA) were mixed together at different proportions under certain humidity conditions using a miscible method to prepare highly regular porous AcNCC/PLA composite films. The composites were characterized using scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The PLA/Ac-NCC-4 showed a uniform pore diameter distribution with diameter of 1.0 mu m to 5.0 mu m. The mechanical properties and thermal stability of the PLA composites were improved with the addition of AcNCC. The pore structure was regular and well distributed. When the AcNCC loading was 4%, the tensile strength and Young's modulus of the composites were 2.07 and 2.41 times higher than that of the pure PLA, respectively. The composites also exhibited high visible light transmission.