Synthesis of a temperature-sensitive waterproof and breathable polyurethane and its application in woolen fabric processing

A novel hydrophilic polyether shape memory polyurethane was prepared from 4,4'- diphenylmethane diisocyanate (MDI), polytetramethylene ether glycol (PTMG), polyethylene glycol (PEG) and the polyoxyethylenetriol (PMG) prepared by us with 1,4-butanediol (BDO) as the chain extender. Several representative properties of the polyurethane such as moisture permeability, water repellent ability, bibulous ability and the responsibility of its properties to environmental temperature were studied. The studies show that the polymer has a better affinity for water, whose critical change temperature is about 23 degrees C. The water vapor transmission rate, WVT (38 degrees C) of the fabric coated with the polyurethane achieves 3 000g/(m(2) center dot 24h), water repellency approaches 7kPa, and the response range to environmental temperature is round about 20 similar to 30 degrees C.