| 摘要 |
PURPOSE:To provide a water-curable material having flexibility and exhibiting a curability upon absorption of water by using a specified block copolymer composed of an ethylene glycol polymer and a vinyl chloride polymer. CONSTITUTION:A polyvinyl chloride polymer wherein both terminals are reactive and an ethylene glycol polymer wherein one terminal is reactive are reacted together to prepare a block copolymer with a structure of A-B-A (wherein A is the ethylene glycol polymer; B is the vinyl chloride polymer wherein vinyl chloride monomer is a main component). A water-curable material consisting of the obtd. block copolymer exhibits flexibility without incorporating a plasticizer, is curable by immersing it in water without incorporating a curing agent and regains reversibly flexibility when water is removed and is therefore suitably used as a catheter, a guide wire, etc. In addition, it is pref. that the number-average MW of A in A-B-A is 1,000-10,000 and the amt. of A is 40-60wt.%. |
