Gas solubility of carbon dioxide in poly(lactic acid) at high pressures: Thermal treatment effect

摘要: The sorption of carbon dioxide in glassy Poly(lactic acid) (PLA) films was studied by quartz crystal microbalance (QCM) at high pressures. Two thermal treat- ments, melted and quenched, were performed PLA with two different L:D contents, 80:20 98:2, compared a third protocol, annealed, used previous work. results obtained show that for pressures higher than 2 MPa, the solubility is larger indicating plays dominant role on this property. treatments only affect gas 98:2. Sorption isotherms temperatures 303, 313, 323 K, below glass transition temperature polymer, up to 5 MPa measured analyzed three models, dual-mode sorp- tion model, Flory-Huggins equation, modified model where Henry's law term substituted equation. This last performs especially well CO2 80:20, due convex upward curvature system. V C 2007 Wiley Periodicals, Inc.