Dab tsi yog qhov txawv ntawm polyether polyols thiab polyethers?
Polyester-type polyol feem ntau yog ua los ntawm cov organic ob lub ntsiab carboxylic acid (anhydride los yog ester) thiab diol (muaj diol) condensation (los yog ester pauv) los yog lactone thiab polyol polymerization, yog ib qho ntawm cov khoom siv tseem ceeb ntawm polyester-hom polyurethane, Yog li dab tsi yog qhov txawv ntawm polyester-type polyol thiab polyol-type polyol?
1. Polyether polyol thiab polyether polyol yog synthesized los ntawm cov khoom sib txawv.
Polyester polyol tau los ntawm condensation cov tshuaj tiv thaiv ntawm binary carboxylic acid thiab diol, thiab lwm yam. Vim muaj ntau yam sib txawv los yog cov txheej txheem kev npaj sib txawv, ntau hom polyester polyols muaj cov khoom sib txawv. Rau polyester polyols, qhov ntsuas tseem ceeb tshaj yog hydroxyl tus nqi, acid nqi, dej, viscosity, molecular hnyav, ntom, xim, thiab lwm yam.
Polyether polyols (polyethers luv luv) yog tsim los ntawm cov tshuaj tiv thaiv polymerization ntawm ethylene oxide, propylene oxide thiab epoxy butane nyob rau hauv ib qho catalyst. Cov txiaj ntsig loj tshaj plaws ntawm polyethers yog tsim los ntawm kev sib txawv ntawm qhov sib ntxiv ntawm PO thiab EO los tsim ntau yam ntawm cov hom phiaj polyether polyols, siv glycerol ua tus neeg sawv cev pib thiab epoxide.
2. Polyether polyols muaj ntau yam phom sij rau polyols.
Cov pa roj carbon steel. Aluminium. Stainless hlau, polyethylene lossis polypropylene, polyester polyols tsis suav hais tias muaj kev phom sij rau kev thauj mus los. Cov kua polyesters muaj qee zaus huab thaum khaws cia rau lub sijhawm ntev ntawm qhov kub thiab txias, nyob ib ncig ntawm 80 degree. Qhov no tuaj yeem raug tshem tawm nrog lub sijhawm luv luv ntawm cov cua sov thiab qhov zoo tsis cuam tshuam. Polyester polyols nyiam nqus dej noo thiab yuav tsum tau khaws cia kom tsis txhob muaj huab cua noo nkag mus.
Neutral polyether alcohols tuaj rau hauv qhov ncauj los yog nrog daim tawv nqaij. Qhov muag. Cov tshuaj toxicity rau mucous daim nyias nyias yog negligible thiab yog li tsis muaj kev tiv thaiv tus kheej thaum siv. Vim yog qhov ua rau alkaline, amine raws li polyether polyols tuaj yeem ua rau tawv nqaij thiab ob lub qhov muag, yog li tsom iav, hnab looj tes thiab lwm yam khoom siv tiv thaiv yuav tsum tau hnav thaum tuav. Thaum khaws cia, tiv thaiv tshav ntuj, los nag thiab hluav taws.
Dab tsi yog qhov sib txawv thiab kev sib txuas ntawm polyester polyols thiab polyether polyols?
Zoo sib xws:
Qhov kawg ntawm cov saw hlau molecular siv los cuam tshuam nrog isocyanates yog tag nrho hydroxyl-valued capped.
Qhov txawv:
Polymer polyol yog vinyl monomer thiab pib polymer raws li lub hom phiaj dav dav polyether polyol nrog acrylonitrile, styrene thiab lwm yam polymers. Feem ntau yog siv nyob rau hauv qhov muag ua npuas ncauj sector.
Polyether polyols feem ntau yog siv hauv cov foams, tawv foams thiab adhesives, feem ntau hauv polyether polyols, feem ntau hauv polyether polyols.
Polyester polyol feem ntau yog tsim los ntawm diacid thiab diol esterification cov tshuaj tiv thaiv, nrog siab hardness. Zoo adhesion, feem ntau yog siv los ua npuas ncauj tawv. Adhesives. Elastomers, thiab lwm yam.
