1546 ポリ乳酸の合成条件とその機械的性質および成形性に関する研究(S11-4 バイオマス由来材料の成形加工と特性評価(4)生分解性プラスチックの成形性と機械的性質,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

抄録

Poly L-lactic acid was synthesized by ROP (ring opening polymerization). The effects of polymerization time, contents of Tin 2-ethylhexanoate as a catalyst, polymerization temperature on Molecular and mechanical properties weight were investigated. The Molecular weight was determined at 30 degrees with Ubelode viscometer. The optical purity of L-lactide, monomer, was measured by a polarimeter. The L-lactide was obtained through pyrolysis and purified. The maximum molecular weight reached 245000 at 160 degrees at polymerization temperature, 0.05 catalyst weight % and 6 hour polymerization time. Conversion rate of L-lactide to PLLA was increased after crystallization starting from 94% to 99.8%. Furthermore, the tensile strength and elongation in the PLLA were 27-47MPa, 2.5-3.5%. These results shows the hard and brittleness in PLLAs compared to other polymers.