Synthesis and characterization of crystallized & cross-linked high water vapor permeable polyurethane

A polyurethane(PU) coating agent was synthesized from 4,4′-diphenylmethane diisocyanate(as soft segment),polytetramethylene ether glycol,polyethylene glycol and self-prepared polyoxyethylenetriol(as hard segment) with 1,4butanediol as chain extender.Several representative properties of the polyurethane,such as water vapor permeability,waterproofness,hydrophility,response to environmental temperature,etc.were studied.The results show that the fabric coated with the PU has water vapor transmission rate achieving over(3 500 g/(m~2·d),) resistance to static hydraulic pressure up to(5 kPa,) velocity of being wetted by water reaching about(11(°)/min,) and response to environment temperature ranging from 15 to(24 ℃.) Meanwhile,the probability of using the PU coating agent to produce intelligent waterproof and breathable fabric was analyzed.