Synthesis of Star-Shaped PLA via Direct Melt Polycondensation: 2. Using <i>D,L</i>-LA as Starting Material

Abstract

Using 1,3,5-benzenetrioxyundecanol (mTU) as the core, and more cheaper D,L-lactic acid (D,L-LA) as starting material, a novel star-shaped poly(D,L-lactic acid) (SPDLLA) was synthesized via direct melt polycondensation with simple process and low-cost. The obtained biodegradable polymer SPDLLA was systematically characterized with the intrinsic viscosity [η], FTIR, 1H-NMR, GPC and XRD. The Tg and crystallinity of all SPDLLA were much lower than that of the linear poly(D,L-lactic acid). When n(D,L-LA) : n(mTU) was 120 : 1, the biggest Mw was 10800, which was bigger than that obtained from L-lactic acid (L-LA). All Mw meet the requirement for drug delivery application.