Poly(L-lactic acid) Metal Organic Framework Composites. Mass Transport Properties

Biodegradable multifunctional polymeric membranes based on poly(L-lactic acid), PLLA, and metal organic framework compounds (MOFs) were developed. PLLA with and without the addition of 5 wt % MOF was melt compounded in a microextruder, and the solubility parameters, water sorption isotherm, and permeability coefficients to oxygen, carbon dioxide, water, ethyl acetate, hexane, and cyclohexane were determined. The sorption capacity of the PLLA MOF composite films increased up to 2-fold at each relative humidity to which it was exposed when compared with the PLLA films. The sorption and desorption curves of the PLLA MOF films show hysteresis. The presence of MOF in the composite films did not significantly modify the permeability coefficients of the PLLA MOF films.