Design of poly(ester imide)/polysulfone multiblock copolymers and their property profiles

Abstract

New multiblock copolymers containing liquid crystalline poly(ester imide) blocks coupled with polysulfone segments have been synthesized by melt transesterification polycondensation. Connecting these segments with different molecular weights offers the opportunity to obtain both non-phase-separated and phase-separated polymers. Phase separation is detected by the occurrence of more than one glass transition as well as by transmission electron microscopy. The resulting properties depend strongly on the morphology. Non-phase-separated multiblock copolymers show synergistic effects with respect to the glass transition and the initial E modulus. The glass transition temperatures as well as the modulus of all multiblock copolymers are higher than those found of the parent homopolymers of the used blocks, which results additionally in a very high thermostability. The synthesized materials could be very interesting for both new membrane materials and barriers with controllable diffusion properties.