Lamellar Morphology in Block Copolymers of Polystyrene and Poly[methyl(3,3,3-trifluoropropyl)siloxane

Abstract

Well-defined polystyrene-block-poly[methyl(3,3,3-trifluoropropyl)siloxane] (PS-b-PMTFPS) diblock copolymers and polystyrene-block-poly[methyl(3,3,3-trifluoropropyl)siloxane]-block-polystyrene (PS-b-PMTFPS-b-PS) triblock copolymers with the volume fraction of PS between 0.46–0.61 were synthesized by anionic polymerization. The phase behavior and morphologies of the block copolymers were investigated via differential scanning calorimetry (DSC), rheological measurements, small-angle X-ray scattering (SAXS), and transmission electron microscopy (TEM). Equilibrium domain orientations of well-ordered lamellar microphase-separated structures were observed in the PS-b-PMTFPS diblock and PS-b-PMTFPS-b-PS triblock copolymer melts. The results showed that the synthesized block copolymers were desirable for achieving long-range order resulting from a high driving force between PS and PMTFPS blocks.