The Thermal and Crystallization Studies of Luffa Fiber Reinforced Poly Lactic Acid Composites

摘要

Poly lactic acid (PLA)—chemically treated fiber of Luffa cylindrica (LC) composites were fabricated by micro-compounding followed by injection molding method. Before reinforcement, LC fibers were exposed to chemical treatment like alkali treatment, bleaching and acid hydrolysis. The chemically treated LC fibers were then modified with Ca salts to explore their uses in bio medical industries. Thermal stability of chemically extracted cellulose fibers of LC and PLA composites reinforced with 2 wt%, 5 wt% and 10 wt% LC fibers were studied by thermo gravimetric analysis (TGA) in the temperature range from 30℃ to 700℃. Better interfacial bonding between fiber and matrix was evidenced by increased thermal stability of composites due to incorporation of fiber. Crystallization and melting behavior of PLA composites were studied in the temperature range from 30℃ to 170℃ at heating rate of 10°/minute. The crystallization temperature and crystallization enthalpy increased up to 2 wt% of LC fiber content and gradually decreased with further increase of fiber content in the composites. Double melting peaks were observed for all composite samples and possible explanations were suggested on the basis of different crystalline structure of PLA and melt crystallization phenomena.