Synthesis and morphology of polyacrylate-poly(dimethyl siloxane) block copolymers for membrane application

Poly(methyl acrylate)-poly(dimethyl siloxane)-poly(methyl acrylate) (PMA-PDMS-PMA) and poly(methyl methacrylate)-poly(dimethyl siloxane)-poly(methyl methacrylate) (PMMA-PDMS-PMMA) triblock copolymers were synthesized with atom transfer radical polymerization technique. Thermodynamic properties of block copolymer solutions were investigated. Solubility parameter differences and Flory-Huggins interaction parameters of block copolymer-solvent systems were evaluated for the membrane application. Morphology study indicated cylindrical micelles of PDMS block copolymers. X-Ray analysis confirmed phase separated morphology of PDMS block copolymers in bulk. The effect of polyvinyl acetate (PVAc) on the morphology and its effect on the gas permeation behavior of PMA-PDMS-PMA triblock copolymer was studied. PMA-PDMS-PMA/PVAc blend membranes were shown a new fibrillar morphology. The gas permeation properties and selectivity of the blend membranes were also reported.