Poly(urea-urethane) polymers with multi-functional properties

Polyurea-urethanes with multifunctional properties were synthesized by reac ting 4,4'-diphenylmethane disocyanate (MDI) with a two diol mixture of poly tetramethylene glycol (PTMG (1000, 2000) and biocidal quaternary ammonium m onomer ((N-benzyl-N-dodecyl-N-bis2-hydroxyethyl) ammonium chloride (BDAC)), and extended with N-(2-hydroxyethyl) ethylene diamine (HEDA) to form PU po lymers. The PU polymer was then grafted with a disperse dye via a coupling agent of epichlorohydrin to form a dye grafted polyurethane with biocidal a nd covalent bond dyeing properties. In consideration of the mechanical prop erties, it is found that both the modulus and the strength of the dye graft ed PU polymer films are lower than those of pure PU polymers due to the bul kiness of their dye molecules. For thermal properties, the dye grafted PU p olymers exhibit higher T(g)h than those without dye molecules. However,neit her the T(g)s nor the T(m)s vary in the presence of BDAC or dye molecules, but they are changed with various chain lengths of the soft segment. For dy eing properties, the effective dyeing efficiency of dye grafted PU is over 85%. Moreover, the dye grafted PU polymers exhibit lower dye migration (M-p %) than those of simple mixtures of PU and dyestuff, and they show a higher grade of color fastness when exposed to light. In the shake method of anti bacterial testing, the modified PU polymers exhibit a long lasting biocidal activity.