Lithium chloride as catalyst for the ring-opening polymerization of lactide in the presence of hydroxyl-containing compounds

Lithium chloride was found to be an effective and biocompatible catalyst fo r the ring-opening polymerization of lactide in the presence of hydroxyl-co ntaining compounds. Ethylene glycol (EG) and methyl alpha-D-glucopyranoside (MGlc) were used as multifunctional initiators. The polymerization was car ried out as 128 degrees C in bulk with 1% (w/w) of LiCl. Polylactide (PLA) of different molecular weights was obtained with varied molar ratios of mon omer/initiator ([M](0)/[I](0)). The LiCl-catalyzed ring-opening polymerizat ion was applied to the synthesis of a number of amphiphilic PLA copolymer w hen poly(ethylene glycol) (PEG), hydroxyethyl cellulose (HEC), and hydroxyp ropyl cellulose (HEC), and hydroxypropyl cellulose (HPC) were used as macro initiators. (C) 1999 John Wiley & Sons, Inc.