Eminyakeni yamuva nje, imikhiqizo ye-polyurethane iye yanda kakhulu, njengamaphaneli okugcina abandayo akhiqizwa yi-Harbin Dong'an Building Sheets e-China, enziwe ngezinto ze-polyurethane.
Ngokuvamile, i-polyurethane ingahlukaniswa ibe i-thermosetting ne-thermoplastic, futhi ingenziwa ibe amapulasitiki e-polyurethane (ikakhulukazi amapulasitiki e-foam), imicu ye-polyurethane (spandex), nama-polyurethane elastomers. Izinto eziningi ze-polyurethane zibizwa nge-thermosetting, njengamagwebu e-polyurethane athambile, aqinile futhi aqinile.
Ukugaywa kabusha kwe-polyurethane kuvame ukusebenzisa izindlela zokugaywa kabusha ngokomzimba, njengoba le ndlela iphumelela futhi iyonga. Ikakhulukazi, ingahlukaniswa ngezindlela ezintathu zokugaywa kabusha:
Le ndlela iwubuchwepheshe bokugaywa kabusha obusetshenziswa kakhulu. Igwebu elithambile le-polyurethane lichotshozwa libe yizicucu zamasentimitha amaningana nge-grinder, futhi ingcina ye-polyurethane esebenzayo ifafazwa ku-mixer. Ingcina esetshenziswayo ngokuvamile inhlanganisela yegwebu le-polyurethane noma i-NCO enqanyuliwe i-prepolymer esekelwe ku-polyphenyl polymethylene polyisocyanate (PAPI). Uma usebenzisa ama-adhesive asekelwe e-PAPI ukuze kuhlanganiswe nokubunjwa, ukuxuba umusi kungabuye kwethulwe. Esikhathini sokuhlanganisa imfucuza ye-polyurethane, engeza u-90% wemfucuza ye-polyurethane kanye ne-adhesive engu-10%, uhlanganise ngokulinganayo, noma wengeze odayi abathile, bese ucindezela ingxube.
Ubuchwepheshe bokwakha isibopho abugcini nje ngokuguquguquka okukhulu, kodwa futhi bunokuhlukahluka okukhulu kwezakhiwo zemishini yomkhiqizo wokugcina. Indlela ephumelela kakhulu yokugaywa kabusha kwemikhiqizo ye-polyurethane ukukhiqiza igwebu le-polyurethane eligaywe kabusha ngokuhlanganisa igwebu lemfucuza elifana nezinsalela zegwebu elithambile, elisetshenziswa kakhulu njengokusekelwa kukakhaphethi, umata wezemidlalo, izinto zokuvala umsindo neminye imikhiqizo. Izinhlayiya ezithambile zegwebu nezinamatheliso zingabunjwa zibe yimikhiqizo efana namaphedi angaphansi kwemoto ezingeni lokushisa elithile nokucindezela; Ngokusebenzisa ingcindezi ephakeme kanye nezinga lokushisa, izingxenye eziqinile ezifana nezindlu zamaphampu zingabunjwa.
Igwebu le-polyurethane eliqinile kanye nokubumba komjovo wokusabela (RIM) i-polyurethane elastomer nakho kungagaywa kabusha ngendlela efanayo. Ukuxuba izinhlayiya zemfucuza nama-isocyanate prepolymers ukuze kubunjwe ngokucindezela okushisayo, njengokwenza abakaki bamapayipi amasistimu okushisa amapayipi. | 2,Ukucindezela okushisayo ukubumba Igwebu elithambile le-Thermosetting polyurethane kanye nemikhiqizo ye-RIM polyurethane inezinto ezithile zokuthambisa ezishisayo kanye nepulasitiki ebangeni lokushisa elingu-100-200 ℃. Ngaphansi kwezinga lokushisa eliphezulu nokucindezela, imfucumfucu ye-polyurethane ingahlanganiswa ngaphandle kokusebenzisa izinto zokunamathisela. Ukuze wenze imikhiqizo egaywe kabusha ifane, kuvame ukudingekile ukuchoboza imfucuza bese ushisa bese uyicindezela ukuze ibumbe.
Izimo zokwakha zincike ohlotsheni lwemfucuza ye-polyurethane kanye nomkhiqizo ogaywe kabusha. Isibonelo, imfucumfucu ye-polyurethane ethambile yegwebu ingashiswa imizuzu eminingana ngengcindezi ye-1-30MPa kanye nebanga lokushisa elingu-100-220 ° C ukuze kukhiqizwe izinto ezibamba ukushaqeka, abaqaphi bodaka, nezinye izakhi.
Le ndlela isetshenziswe ngempumelelo ekugayweni kabusha kwezingxenye zezimoto ze-RIM zohlobo lwe-polyurethane. Isibonelo, amaphaneli eminyango yemoto namaphaneli wezinsimbi angenziwa cishe nge-6% RIM polyurethane powder kanye ne-fiberglass engu-15%. | 3,Isetshenziswa njenge-filler Igwebu elithambile le-polyurethane lingashintshwa libe yizinhlayiya ezinhle ngokuchotshozwa kwezinga lokushisa eliphansi noma inqubo yokugaya, futhi ukuhlakazwa kwezinhlayiya ezinjalo zengezwa kuma-polyols okukhiqiza igwebu le-polyurethane noma eminye imikhiqizo, engagcini nje ngokubuyisela imfucumfucu ye-polyurethane, kodwa futhi inciphisa ngokuphumelelayo. izindleko zomkhiqizo. Okuqukethwe kwempushana ephukile kugwebu le-MDI elisekelwe emakhazeni elilashwe nge-polyurethane eliguquguqukayo kunomkhawulo ku-15%, futhi u-25% wempushana ephukile ungongeza ku-TDI esekelwe kugwebu elilashiwe elishisayo kakhulu.
Enye inqubo yokwengeza imfucumfucu yegwebu eqoshwe ngaphambili ku-polyether ethambile eyigwebu, bese emanzi uyigaye esigayweni esifanelekile ukuze kwakheke ingxube "ye-polyol egaywe kabusha" equkethe izinhlayiya ezinhle zokukhiqiza igwebu elithambile.
Imfucuza ye-RIM polyurethane ingachotshozwa ibe yimpushana, ixutshwe nezinto ezingavuthiwe, bese yenziwa ama-elastomers e-RIM. Ngemuva kokuthi imfucuza ye-polyurethane eqinile yegwebu kanye ne-polyisocyanurate (PIR) imfucumfucu yegwebu isichotshoziwe, ingasetshenziswa futhi ukwengeza u-5% wezinto ezigaywe kabusha ekuhlanganisweni ukuze kukhiqizwe igwebu eliqinile. |
Eminyakeni yamuva nje, kuye kwavela indlela entsha yokubuyisela amakhemikhali
Ithimba leNyuvesi yase-Illinois eliholwa uSolwazi Steven Zimmerman lenze indlela yokubola imfucuza ye-polyurethane bese iguqulwa ibe eminye imikhiqizo ewusizo.
Umfundi othweswe iziqu u-Ephraim Morado unethemba lokuthi uzophinda asebenzise ama-polymer ngezindlela zamakhemikhali ukuxazulula inkinga yemfucuza ye-polyurethane. Kodwa-ke, i-polyurethane inokuzinza okuphezulu kakhulu futhi yenziwe ngezingxenye ezimbili okunzima ukubola: ama-isocyanates nama-polyols.
Ama-Polyols angukhiye wenkinga, njengoba ekhishwa ku-petroleum futhi awawonakali kalula. Ukuze kugwenywe lobu bunzima, ithimba locwaningo lamukele iyunithi yamakhemikhali e-acetal eyonakala kalula futhi encibilika emanzini. Imikhiqizo yokucekela phansi eyenziwe ngokuncibilikisa ama-polymer ane-trichloroacetic acid ne-dichloromethane ekamelweni lokushisa ingasetshenziselwa ukukhiqizwa kwezinto ezintsha. Njengobufakazi bomqondo, iMorado ingaguqula ama-elastomers asetshenziswa kabanzi emaphaketheni nasezinxenyeni zezimoto abe izinto zokunamathisela.
Kodwa-ke, ukuhlehla okukhulu kwale ndlela entsha yokugaywa kabusha yizindleko kanye nobuthi bezinto ezingavuthiwe ezisetshenziselwa ukusabela. Ngakho-ke, abacwaningi okwamanje bazama ukuthola indlela engcono futhi eshibhile yokufeza inqubo efanayo ngokusebenzisa izincibilikisi ezithambile ezifana noviniga wokunciphisa.
Esikhathini esizayo, Harbin Dong'an isakhiwoishidis inkampaniizophinde futhi ilandele eduze ukuqanjwa kabusha kwale mboni futhi iqhubeke nokutshala imali kwezobuchwepheshe kanye nobuchwepheshe bokuvikela imvelo, iqhubeke nokusungula izinto ezintsha ukuze yenze amaphaneli e-Dong'an's polyurethane angabi nobungane futhi abe nempilo. Sikholelwa futhi ukuthi kuzoba nobuchwepheshe obuningi bokuvikela imvelo obuzozalwa esikhathini esizayo.
Isikhathi sokuthumela: Nov-09-2023