Synthesis and characterization of PEG-segmented polyurethane

PEG (Mn = 1000)-segmented polyurethanes, with hard segment percentage of 40%, 50% and 55% and named PU-H40, PU-H50 and PU-H55 respectively, were synthesized by bulk polymerization. The structure of PU was characterized by FTIR, DSC, and GPC. Mechanical properties, water contact angles and water vapor transmit rate(WVTR) were also tested. FTIR and DSC showed that the degree of microphase separation increased with the hard content. Mechanical test showed the tensile strength of PU-H50 to be 25 MPa, the highest tensile strength of the PU series. By the use of PEG as soft segment, the surface hydrophilicity of the materials increased dramatically. Owing to its high degree of microphase separation and the mobility of soft segment, the water contact angle of PU-H55 attained to 33 degrees. The WVTRs of PU-H40, PU-H50 and PU-H55 were 789 g/m2/24h, 705 g/m2/24h and 623g/m2/24h respectively. These data suggest that the materials are suitable for fabricating such biomedical articles as surgical gloves, wound dressing and medical protective coating.