Helitaanka polyurethane [PU] waxay dib ugu noqotaa sanadka 1937 Otto Bayer iyo asxaabtiisa shaybaarada IG Farben ee Leverkusen, Jarmalka.Shaqooyinka bilowga ah waxay diiradda saarayaan alaabta PU ee laga helay aliphatic diisocyanate iyo diamine samaynta polyurea, ilaa sifooyinka xiisaha leh ee PU laga helay diisocyanate aliphatic iyo glycol, ayaa la xaqiiqsaday.Polyisocyanates waxay noqdeen ganacsi ahaan la heli karo sanadka 1952, wax yar ka dib wax soo saarka miisaanka ganacsiga ee PU ayaa la arkay (dagaalkii labaad ee aduunka ka dib) ee toluene diisocyanate (TDI) iyo polyester polyols.Sanadihii xigay (1952-1954), nidaamyada polyester-polyisocyanate ee kala duwan ayaa waxaa sameeyay Bayer.
Polyester polyols waxaa si tartiib tartiib ah loogu beddelay polyeter polyols iyadoo ay ugu wacan tahay faa'iidooyinkooda dhowr ah sida qiime jaban, sahlanaanta maaraynta, iyo xasilloonida hydrolytic ee hore.Poly (tetramethylene ether) glycol (PTMG), waxaa soo bandhigay DuPont 1956 iyadoo polymerizing tetrahydrofuran, oo ah kii ugu horreeyay ee polyether-ka ganacsi ahaan loo heli karo.Ka dib, 1957, BASF iyo Dow Chemical waxay soo saareen polyalkylene glycols.Iyada oo ku saleysan PTMG iyo 4,4'-diphenylmethane diisocyanate (MDI), iyo ethylene diamine, fiber Spandex ah oo la yiraahdo Lycra waxaa soo saaray Dupont.Tobankii sano ee la soo dhaafay, PU waxay ka qalin jabisay xumbo PU dabacsan (1960) ilaa xumbo PU adag (polyisocyanurate foams-1967) sida dhowr walax oo afuufaya, polyols polyeter, iyo polymeric isocyanate sida poly methylene diphenyl diisocyanate (PMDI) ayaa la helay.Xumboyada PU ee ku salaysan PMDI waxay muujiyeen iska caabin kulayl oo wanaagsan iyo dib u dhac olol.
Sannadkii 1969-kii, tignoolajiyada PU Reaction Injection Molding [PU RIM] ayaa la soo bandhigay taas oo u sii gudubtay Reinforced Reaction Injection Molding [RRIM] oo soo saartay wax qabad sare oo PU ah kaas oo 1983 keenay baabuurkii ugu horreeyay ee caag ah ee Maraykanka.Sannadihii 1990-aadkii, iyadoo ay ugu wacnayd kor u kaca wacyiga ku aaddan khataraha isticmaalka chloro-alkanes sidii wax-afuufiyeyaal (Montreal Protocol, 1987), dhawr jeer oo kale oo wax qarxin ah ayaa ku soo daatay suuqa (tusaale, carbon dioxide, pentane, 1,1,1,2- tetrafluoroethane, 1,1,1,3,3- pentafluoropropane).Isla mar ahaantaana, laba xidhmo oo PU ah, PU-polyurea tignoolajiyada buufinta ayaa soo galay horudhac, kaas oo dhaliyay faa'iidooyin la taaban karo oo ah qoyaan la'aanta dareen-celinta degdega ah.Dabadeed ubaxday xeeladda ka faa'iidaysiga polyols saliidda cuntada ku salaysan ee horumarinta PU.Maanta, adduunka PU wuxuu ka yimid waddo dheer oo ka timid isku-dhafka PU, PU composites, non-isocyanate PU, oo leh codsiyo badan oo kala duwan oo kala duwan.Xiisaha PU ayaa kacday sababtoo ah iskudarkooda fudud iyo borotokoolka codsiga, fudud (wax yar) falcelinta aasaasiga ah iyo sifooyinka sare ee alaabta kama dambaysta ah.Qaybaha dacwadu waxay bixiyaan sharaxaad kooban oo ku saabsan alaabta ceeriin ee looga baahan yahay isku dhafka PU iyo sidoo kale kiimikada guud ee ku lug leh wax soo saarka PU.
Baaq: Maqaalka waxaa laga soo xigtay © 2012 Sharmin iyo Zafar, shatiga InTech.Kaliya xiriirinta iyo barashada, ha sameynin ujeeddooyin kale oo ganacsi, ma matalo aragtida iyo fikradaha shirkadda, haddii aad u baahan tahay inaad dib u daabacdo, fadlan la xiriir qoraaga asalka ah, haddii ay jirto xad-gudub, fadlan nala soo xiriir isla markaaba si aad u tirtirto howsha.