Preparation, characterization and properties of waterborne polyurethane modified through copolymerization by hydroxy-terminated silicon oil

A series of waterborne polyurethane emulsions modified by copolymerization with WACKER IM 22, RHODORSIL OIL 1647 V60, KF-6001 and traditional hydroxy-terminated silicon oil respectively for leather finishing were synthesized, and characterized with GPC, DSC, TEM and TGA and their finishing properties on leathers were measured. The results showed that, the number average relative molecular weight decreased, while the thermal decomposability was similar to the unmodified waterborne polyurethane. The compatibility of soft and hard segments of waterborne polyurethane modified by WACKER IM 22 was good. The freezing resistance and leveling effect were good when the mass ratio of the WACKER IM 22 to polypropylene glycol was 20%. The binding power was good when the leathers were finished by waterborne polyurethane modified by hydroxyl based silicon oil. The hand feeling of said leather style was nice and soft and the water resistance property was increased.