Ngenxa yenqubo yokukhiqiza i-urea formaldehyde resin, ukuthuthukiswa kwemboni ye-melamine kuhlangabezane nenqubo esheshayo.Umbhalo wocwaningo wabika okokuqala ngokwenziwa kwe-melamine resin ngo-1933. I-America Cyanamide Company yaqala ukukhiqiza nokudayisa ama-melamine powder laminates kanye nama-coatings njll ngo-1939. Ngawo-1950 nawo-1960, iJapane yabona ukusungulwa kwezimboni ngokugcwele.inhlanganisela ye-melamine.Ngawo-1960, i-China yaqala ukwethula ubuchwepheshe bokukhiqiza i-melamine.Ngemva kwamashumi eminyaka entuthuko, amandla okukhiqiza imikhiqizo ye-melamine manje asephezulu kakhulu emhlabeni, ebalwa ngaphezu kuka-80 9/6 wesabelo semakethe yomhlaba wonke.
Ukuze sazi okwengeziwe nge-melamine powder, ake sibheke inqubo yokukhiqiza i-melamine powder kuqala.
Impahla eyinhloko yemikhiqizo ye-melamine inhlanganisela yokubumba i-melamine, eyaziwa nangokuthi i-melamine formaldehyde resin powder noma i-melamine powder.Impahla eluhlaza eyinhloko ye-melamine powder i-melamine resin ene-reactivity ephezulu kanye nokuxhumanisa.I-melamine resin iyi-polymer ene-dandelion ephezulu ehlanganiswe ukusabela kwamakhemikhali e-melamine kanye nesisombululo esinamanzi se-formaldehyde ngaphansi kwezimo eziqinile.Ukusabela kuvamise ukwenziwa kureactor efakwe iyunithi enyakazayo, yokushisisa kanye ne-condensing, ngokuvamile ngezinyathelo ezimbili.
1. Isinyathelo sokuqala ukusabela kokwengeza.Okokuqala, engeza isixazululo esinamanzi se-formaldehyde esingu-37% emkhunjini wokusabela futhi ulungise i-pH ibe ngu-7-9 ukuze uthole i-alkaline engathathi hlangothi noma ebuthakathaka.Bese wengeza inani elifanele le-melamine ukwenza i-moore formaldehyde ne-melamine phakathi kuka-2 no-3. Izinga lokushisa le-reactor lalungiswa ukuze lishise kancane libe ngu-60-85 ° C. Ngalesi sikhathi, i-formaldehyde ne-melamine yayivinjwe ukusabela kwe-methylolation. , futhi i-oligomer eqondile ye-melamine equkethe i-1 kuya ku-6 amaqembu e-methylol yakhiwa.Ukusabela okungenhla kuwukusabela kwe-exothermic okungabonakali.Uma iphezulu ingxenye ye-formaldehyde, kuba lula ukwenza i-polymethylol melamine.
2. Isinyathelo sesibili ukusabela kwe-condensation.Ngaphansi kwezimo zokushisa eziphakeme, i-methylol melamine esebenza kakhulu iphinde ifakwe i-etherified noma i-polycondensed ukuze ikhiqize inhlanganisela ye-resin eqondile exhumene equkethe ibhondi ye-methylene noma ibhondi ye-dimethylene ether.ngezindlela ze-intramolecular noma zamangqamuzana endaweni ene-acidic medium.Uma inani leqembu le-methylol lincane, isibopho se-methylene ngokuvamile sibusa;ku-resin esekelwe ku-sorghum, isibopho se-dimethylene ether ngokuvamile siyakhiwa, futhi isibopho se-methylene siyakhiwa.Izinga elikhulu lokujiya kokusabela kwe-polycondensation, kunciphisa ukuncibilika kwamanzi kwesixazululo se-melamine formaldehyde resin kanye nokubonakala okukhulu kwe-viscosity.
Kule nqubo yokusabela engenhla, isisindo samangqamuzana omkhiqizo wokugcina sinqunywa izimo ezithile zokusabela, futhi ukuncibilika kwamanzi komkhiqizo nakho kushintsha kakhulu.Amafomu omkhiqizo atholakala kabanzi kusukela ezixazululweni ze-resin kuya ezintweni eziqinile ezingancibilikisiwe nezingancibiliki.Isixazululo se-resin sinokuzinza okubi futhi asihambisani nokulondolozwa.Ekukhiqizeni kwangempela, kuvame ukusetshenziswa njenge-substrate kanye nezinto ezingaphili ezifana ne-d-cellulose, i-wood pulp, i-silica, ama-colorants.Yenziwa ibe yimpuphu okuqinile okubizwa ngokuthi impushana ye-melamine ngesigayo sebhola esomisa isifutho.
I-Huafu Chemicals iyifekthri enjalo ekhiqizayoI-melamine resin powder.Uma unentshisekelo, sicela usithinteEmail : melamine@hfm-melamine.com
Isikhathi sokuthumela: Sep-20-2019