Composite film materials based on poly(D,L-Lactide) and acexamic acid

摘要

The influence of the hydrophilicity and molecular mass of poly(D,L-lactide) on the solubility of acexamic acid in the polylactide film and on the rate of its release from the polymer was studied. The release of acexamic acid from the polylactide film is described by a two-step model according to which the first step consists in dissolution of acexamic acid occurring in the intrinsic crystalline phase, and the second step, in the release of acexamic acid dissolved in the poly(D,L-lactide) phase. The results of conductometric measurements show that the limiting solubility of acexamic acid in poly(D,L-lactide) is higher in more hydrophilic films prepared using zinc lactate and amounts to 5-8. The rate of the acexamic acid release increases with a decrease in the molecular mass of poly(D,L-lactide).