Lebitso la Sehlahiswa:polyurethane

Sebopeho sa limolek'hule tsa sehlahisoa:

Lintho tsa Lik'hemik'hale:

Li-polyurethanes li ile tsa hlahisoa ka lekhetlo la pele 'me tsa batlisisoa ke Dr. Otto Bayer ka 1937. Polyurethane ke polymer eo karolo e pheta-phetoang e nang le karolo ea urethane. Li-urethane li tsoa ho li-carbamic acid tse teng feela ka sebopeho sa li-ester tsa tsona[15]. Monyetla o moholo oa PU ke hore ketane ha e entsoe feela ka liathomo tsa khabone empa e entsoe ka li-heteroatom, oksijene, khabone le nitrogen[4]. Bakeng sa lisebelisoa tsa indasteri, motsoako oa polyhydroxyl o ka sebelisoa. Ka mokhoa o ts'oanang, metsoako ea naetrojene ea poly-functional e ka sebelisoa likhokahanong tsa amide. Ka ho fetola le ho fetola metsoako ea polyhydroxyl le polyfunctional nitrogen, li-PU tse fapaneng li ka etsoa [15]. Li-resin tsa polyester kapa polyether tse nang le lihlopha tsa hydroxyl li sebelisoa ho hlahisa polyesteror polyether-PU, ka ho latellana[6]. Phapang ea palo ea li-substitutes le sebaka pakeng tsa liketane tsa makala le ka hare ho makala li hlahisa li-PU ho tloha ho linear ho ea ho branched le 9exible ho ea thata. Linear PUs e sebelisetsoa ho etsa likhoele le ho bopa[6]. Flexible PUs e sebelisoa tlhahisong ea li-agent tse tlamang le liphahlo[5]. Lipolasetiki tse tenyetsehang le tse thata, tse etsang boholo ba li-PU tse hlahisoang, li ka fumaneha ka mefuta e fapaneng indastering[7]. Ho sebelisa li-prepolymers tse tlase tsa molek'hule, li-copolymers tse fapaneng li ka hlahisoa. Sehlopha sa terminal sa hydroxyl se lumella li-blocks tse fapaneng, tse bitsoang likarolo, hore li kenngoe ketane ea PU. Ho fapana ha likarolo tsena ho etsa hore ho be le maemo a sa tšoaneng a matla le elasticity. Li-blocks tse fanang ka karolo e thata ea kristale le tse nang le ketane extender li bitsoa likarolo tse thata[7]. Tse fanang ka karolo ea rabara ea amorphous 'me e nang le polyester / polyether li bitsoa likarolo tse bonolo. Khoebong, li-polymer tsena tsa block li tsejoa e le Segmented Pus

Kopo:

Flexible polyurethane haholo-holo sebopeho se nang le thermoplasticity, se nang le botsitso bo betere, ho hanyetsa lik'hemik'hale, ho tiea le thepa ea mochine ho feta foam ea PVC, e nang le phapang e fokolang ea khatello. E na le mohatsela o motle oa mocheso, ho thibela molumo, ho hanyetsa ho tsitsipana le thepa e khahlanong le chefo. Ka hona, e sebelisoa e le ho paka, ho kenya molumo le lisebelisoa tsa ho sefa. Plastiki e thata ea polyurethane e bobebe, e kenya molumo, ho kenya mocheso o phahameng, ho hanyetsa lik'hemik'hale, thepa e ntle ea motlakase, ho sebetsa habonolo le ho monya metsi a tlase. E sebelisoa haholo-holo e le thepa ea mohaho bakeng sa kaho, koloi, indasteri ea lifofane, ho kenya mocheso le mocheso oa mocheso. Ts'ebetso ea polyurethane elastomer lipakeng tsa polasetiki le rabara, ho hanyetsa oli, ho hanyetsa ho roala, ho hanyetsa mocheso o tlase, ho hanyetsa botsofali, ho thatafala ho phahameng, elasticity. E sebelisoa haholo-holo indastering ea lieta le indastering ea bongaka. Polyurethane e ka boela ea etsoa li-adhesives, li-coatings, letlalo la maiketsetso, joalo-joalo.