Study on the Synthesis of Polylactic Acid through 2,4-Toluylene Diisocyanate Chain Extension
Youning Chen · Synthetic Materials Aging and Application · 2009
Polylactic acid with low molecular weight was prepared by the direct melt polycondensation,then 2,4-toluylene diisocyanate(TDI) was used as chain extender to improve the molecular weight.The influence of reaction temperature,time and the amounts of TDI on molecular weight were studied.The products were characterized by IR,DSC and GPC.The results indicates that the molecular weight of chain extension products could be 3.72 times higher than before under the condition of 170℃,0.09MPa,10%TDI as chain extender for 1.5h.