Polyurethane Prepolymer Classification
Mar 31, 2021
Raws li cov tshuaj tiv thaiv cov yam ntxwv ntawm pawg davhlau ya nyob twg, polyurethane prepolymers tuaj yeem muab faib ua: isocyanate-terminated prepolymers, hydroxyl-terminated prepolymers, blocked group-muaj prepolymers, thiab lwm pab pawg xws li terminal silyl pawg thiab acrylate-terminated prepolymers. Polyurethane prepolymer ntawm ester.
Prepolymers nrog NCO kawg pab pawg qee zaum hu ua hloov pauv polyisocyanates, uas muaj cov yam ntxwv ntawm cov tshuaj tiv thaiv siab, yooj yim cuam tshuam los ntawm cov dej noo, thiab lwm yam, thiab muaj lub sijhawm cia luv luv; prepolymers nrog OH kawg pawg hu ua hydroxyl-terminated Prepolymers muaj kev ua haujlwm dav dav thiab lub sijhawm cia ntev dua.
Lawv feem ntau yog siv los ua tus neeg sawv cev tseem ceeb ntawm cov nplaum. Ib tus neeg sawv cev thaiv cov khoom siv hydrogen yog siv los cuam tshuam nrog NCO pab pawg los tiv thaiv cov pab pawg NCO dawb hauv prepolymer kom tau txais cov khoom thaiv polyurethane prepolymer. Cov txheej los yog nplaum npaj los ntawm hom prepolymer no yog rhuab thiab unsealed tom qab kev tsim kho, thiab NCO pab pawg neeg yog regenerated, thiab tom kawg koom nyob rau hauv crosslinking cov tshuaj tiv thaiv kom solidify lub system.
