Synthesis and properties of silicone-modified polyurethane

To obtain a PU film with good water-repellency,a series of silicone modified polyurethane(Si-PU) block polymers were synthesized from isophorone diisocyanate(IPDI),polyoxypropyleneglycol(PPG),hydroxy-terminated poly-dimethylsiloxane(DHPDMS),1,4-butanediol(BDO) and trihydroxymethylpropane(TMP).The influence of the mass percentage of DHPDMS on the properties of polymer solution and polymer film was explored.The FT-IR spectra showed that the silicone chain segments were incorporated into PU macromolecule.The water contact angle of the polymer film changed from 76.8°to 102.5°when the mass percentage of DHPDMS increased from 0 to 10%,indicating that the introduction of silicone into the film has made it possess good water repellency and thermal stability.Variation of the content of DHPDMS has little effect on the mechanical property of the film.The film has good water-repellent and adhesive properties,showing its excellent application.