INFRARED DICHROISM STUDY OF SEGMENTED POLYURETHANEUREA WITH TRIBLOCK POLYETHER SOFT SEGMENTS

Infrared (IR) dichroism study of segmented polyurethaneurea (SEUU) with ABA type triblock copolymer as a soft segment was carried out, where A stands for poly(oxyethylene) (PEO) and B stands for poly(oxytetramethylene) (PTMO). IR dichroism analysis of SEUU films under elongation suggested that the introduction of PEO units to the ends of PTMO brought about more aggregation of the hard segments, i.e., the better microphase separation in SEUU than segmented polyurethaneurea (SPUU) prepared from PTMO. Under uniaxial extension, the crystalline hard segment domain oriented transverse to the stretch direction at early stage, the degree of orientation being larger with the increase of PEO content. The larger was the PEO content, the better the microphase separation in SEUU.