Modification Research And Molecular Simulation Of Bacterial Cellulose And Its Ester Derivatives Reinforced Polylactide

Bacterial Cellulose(BC) was functionalized with several organic acids via esterification reaction, such as acetic acid, hexanoic acid, lauric acid. BC-Acetate(BC-C2), BC-hexanoate(BC-C6), BC-laurate(BC-C12) were synthesized. BC and these esterification products of BC were all used as reinforcement for polylactide (PLA) according to thermally induced phase separation (TIPS).The composite materials of BC or the esterificaton products of BC with PLA were prepared and tested by IR, SEM, DSC and TGA. The results showed that BC or the esterification products of BC were uniformly distributed in PLA, and they cut down the crystallinity degree, improved the thermal degradation and viscoelastic behaviour of PLLA in the composites. But they didn't show a great impact on mobility of PLA chain and its processability. Meanwhile, Td, young's modulus and tensile strength of PLA was improved with BC and their esteritificaton products introduced of the length of branched esterification chain.In this paper, the systems of polymer and their composites, including BC, PLA, BC and PLA, BC-C2 and PLA, BC-C6 and PLA, BC-C12 and PLA, were simulated by the 'Materials Studio' soft based on the COMPASS force field. Meanwhile the interactions among BC and other polymers were investigated. The existent states of molecules were studied. The results of molecular simulation not only hold the experimental conclusions, but also obtained a deep comprehension about relationships between molecular structure and macroscopical properties of blends. Conversely the simulation results had certain guiding effect on the experimental direction.