I-Melamine-formaldehyde resin (MFR) iyirensi ye-amino ebeka ukushisa enobulukhuni obuhle, ukuqina kokushisa, nokungafihli lutho. Uma kuqhathaniswa ne-urea-formaldehyde resin (UF), i-MF resin inokumelana kangcono namanzi kanye nokumelana nesimo sezulu. Ngakho-ke, isetshenziswa kabanzi ekugqokeni kwephaneli yangaphandle, izendlalelo zokuhlobisa phansi ngokhuni kanye nemikhiqizo ye-veneer. Kodwa-ke, ukushiyeka okunjengokuqina okuphezulu, ukuqhekeka kalula, nesikhathi esifushane sokugcina se-melamine formaldehyde resin kunciphisa ukusetshenziswa kwayo. I-MF resin ivame ukusetshenziselwa ukulungisa iphepha lefilimu elinamathelayo elifakiwe. I-Plywood kanye ne-blockboard ebhekene nephepha lefilimu elinamathelayo elihlanganisiwe libizwa ngokuthi amabhodi emvelo. Bathandwa ngabathengi ngenxa yokungagugi, ukungangeni kwamanzi, nemibala ehlukahlukene.
Kodwa-ke, lapho umswakama wemvelo ushintsha, isisekelo sebhodi lezinto eziphilayo sijwayele ukuvuvukala noma ukuncipha, okuholela ekucindezelekeni okungalingani kwangaphakathi. Ungqimba olungaphezulu lwe-MF resin luyaphuka futhi alukwazi ukuguquguquka kahle, futhi lujwayele ukuqhekeka ngaphansi kwengcindezi. Ngakho-ke, ukuthuthukisa ukuguquguquka kwe-MF resin kanye nokuthuthukisa inkinga yayo ye-brittleness yizihluthulelo zokuxazulula inkinga yokuqhekeka kwe-resin kanye nokwenza ngcono ikhwalithi yemikhiqizo yayo yokuhlobisa. Lesi sihloko sifingqa ngokuyinhloko inqubekelaphambili yocwaningo lokuguqulwa kokuqina kwe-MF resin, ngenhloso yokuhlinzeka ngesiqondiso sethiyori kanye nesisekelo sobuchwepheshe sokuxazulula inkinga ye-brittleness ye-MF resin.
1. Izici zesakhiwo se-MF
I-MF resin iyinhlanganisela ye-triazine ring polymer eyakhiwe yi-condensation ye-melamine ne-formaldehyde futhi ixhunywe yi-methylene noma i-ether bond. Inezici zamakhemikhali ezinzile kanye nesakhiwo esiqinile. Ukwakhiwa kwe-resin ye-MF kuhlukaniswe izigaba ezimbili: isigaba sokuqala ukusabela okwengeziwe kwe-melamine ne-formaldehyde. Ngaphansi kwezimo ezingathathi hlangothi noma ze-alkaline, i-melamine ithola i-hydroxymethylation ukuze ikhiqize ama-hydroxymethylmelamine ahlukene angu-9. Isigaba sesibili ukusabela kwe-condensation. I-Melamine isabela nge-methylolated melamine, noma i-methylolated melamine idlula ekuzibopheni ngokwayo ukuze ikhiqize ama-oligomer axhunywe i-methylene namabhondi e-ether. Endaweni enenani le-pH lika-7 kuya ku-8, ukuxhunywa kwebhuloho le-methylene kuyabusa; endaweni enenani le-pH elingaphezu kuka-9, ukuxhunywa kwebhondi ye-ether maningi amathuba okuthi kwakheke.
Ngemuva kokuxhumanisa nokuphulukiswa kwe-resin ye-MF, ukunamathela okusobala okungagugi, ukumelana ne-asidi ne-alkali kungatholakala. Nakuba i-coating ephulukisiwe inobunzima obukhulu, ibuye ibe brittle. Isizathu esiyinhloko ukuthi i-resin ye-MF iqukethe inani elikhulu lamasongo e-triazine axhunywe namaqembu e-methylene. Amaringi e-triazine azinzile ngokwedlulele ngaphansi kwezimo zomthelela futhi anzima ukuwohloka nokumunca amandla omthelela. Amabhondi e-methylene kuphela angakwazi ukumunca iningi lamandla, okwenza amabhondi e-methylene aphuke futhi abonise ukuqina. Ukwelashwa okungaphelele kwe-MF resin kuzodala ukuqhekeka kwe-resin. Njengoba ukuphulukiswa kwe-resin kwenzeka ikakhulukazi phakathi kwamaqembu e-hydroxyl, amanye amaqembu e-hydroxyl angazange abambe iqhaza ekuhlanganiseni azohlala kunhlaka ngemva kokwelashwa. Lawa maqembu e-hydroxyl ane-hygroscopicity ethile. Njengoba umswakama wemvelo ushintsha ngokuphindaphindiwe, amaqembu e-hydroxyl yamahhala azongena emijikelezweni ye-hygroscopic kanye ne-desorption futhi kancane kancane akhiqize ukucindezeleka, okubangela ukuqhekeka kwe-resin enamathelayo futhi kube nomthelela omkhulu ekubukekeni nokusebenza komkhiqizo.
Ukuvumelana nezimo kwe-MF resin kungathuthukiswa ngempumelelo ngokunciphisa ukuminyana kokuxhumanisa kwe-MF resin nokwelula ubude bayo beketango obuguquguqukayo. Kodwa-ke, ukuncishiswa kokuqina kokuxhumanisa kusho ukuthi ukwakheka okuqinile kweringi ye-triazine kunhlaka kuyahlakazeka. Ngakho-ke, ukuqina kwendawo kanye nokumelana nokugqoka kwe-MF resin kuzothinteka ngamazinga ahlukahlukene. Lapho wenza ukuguqulwa kokuqina, kufanele kuqashelwe ukugcina ubulukhuni be-MF resin futhi ungabhubhisi izakhiwo zayo ezinhle kakhulu. Ukukhetha indlela efanelekile yokuguqula ukuze kuthuthukiswe ukuguquguquka kwe-MF resin kubaluleke kakhulu ekwandiseni ububanzi bokufaka kwe-MF resin.
2. Indlela yokuguqula eqinile ye-MF resin
Ukuguqulwa okuqinile kuvame ukusetshenziselwa ukwandisa amandla ama-polymers aqinile axhumene ukuze kuthuthukiswe ukumelana nomthelela kanye nokumelana nokukhathala kwe-polymer ngaphandle kokucekela phansi ukuqina kwasekuqaleni nokuzinza kwe-polymer. Izindlela zokuguqula eziqinile ezifanele i-MF resin ngokuvamile zingahlukaniswa zibe izinhlobo ezimbili, okungukuthi ukuguqulwa kokuqina kwangaphandle kanye nokuguqulwa kokuqina kwangaphakathi. Ukuguqulwa kokuqina kwangaphandle kubhekisela ekwengezeni amaqembu esigaba sokuqinisa kunhlaka ye-MF ngokuhlanganisa ukwakha isakhiwo esixhumene ne-MF ukuvimbela izindandatho ze-triazine ukuthi zisondelane ukuze kufezwe injongo yokuqina. Izindlela ezivame ukusetshenziswa zangaphandle zokuqinisa i-MF resin zihlanganisa:
I-1) Engeza i-nano-SiO2, i-nano-cellulose namanye ama-nanoparticles;
I-2) Sebenzisa ama-polymer amaketanga amade aguquguqukayo afana ne-polyethylene glycol copolymers ukwakha amanethiwekhi e-polymer angena ngaphakathi (IPNS) ku-resin ye-MF;
3) Sebenzisa izinto ze-fiber ezifana ne-polyvinyl chloride ukuxhuma ama-resin e-MF ndawonye ukuze uthuthukise ukuqina kwesakhiwo se-resin.
Ukuguqulwa kokuqina kwangaphakathi kushintsha ukwakheka kwamangqamuzana eresin ye-MF ngokubamba iqhaza ekwelapheni kwenhlaka ye-MF, kunwebe ukuxhumana okuguquguqukayo phakathi kwamasongo e-triazine, nokunciphisa ukuminyana kokuxhumanisa ukuze kuzuzwe umphumela oqinisayo. Izindlela zokuqinisa ngaphakathi zihlanganisa:
1) Yethula ama-molecule amaketanga amade aguquguqukayo phakathi kwezakhiwo zeringi ye-triazine ye-MF resin ukuze kuhlakazwe isakhiwo esiqinile;
2) Sebenzisa abicah ukunweba uxhumano nezimo phakathi MF resins;
3) Vimba iqembu elisebenzayo le-hydroxyl le-MF resin futhi unciphise ukuminyana kokuxhumanisa kwe-resin. Izilungisi ezisetshenziswa kakhulu zangaphakathi eziqinisayo zifaka i-polyvinyl alcohol, i-polyurethane, i-caprolactam, njll.
3. Izidingo ezikhethekile ze-MF resin for impregnation
Kunezindlela eziningi eziqinisayo ze-MF resin, kodwa akuzona zonke ezilungele ukumithisa i-MF resin. Ukuguqulwa okuqinile kwe-resin ye-MF yokukhulelwa kumele kuhambisane nezimo zokukhiqiza zephepha lefilimu elinamathelayo, ngakho-ke linezidingo ezithile ezikhethekile. Uma sisebenzisa i-MF resin ekukhulelweni, akufanele sicabange kuphela ukumelana nokuqhekeka, ukumelana nokugqoka kanye nokuguquguquka ngemva kokuphulukiswa kwe-resin, kodwa futhi sinake uketshezi, ukuvuthwa kanye nezinga lokuphulukisa kwangaphambili le-resin eguquliwe ngaphambi kokuphulukiswa.
Ukungamanzi kahle kwe-MF resin kuzodala izimbali ezomile phezu kwe-veneer yephepha lefilimu elinamathelayo elifakwe emanzini, likhiqize amachashaza amhlophe afiphele ebusweni bomkhiqizo, enze ukonakala. Ukungangeneli kahle kwe-MF resin kuzodala ukungatheleleki okwanele, okuholela ekuntulekeni kweglue noma indawo engalingani endaweni yomkhiqizo. I-inorganic nano-wear-resistant materials ingakhuphula ukuqina kanye nezakhiwo ezingagugi ze-MF resin, kodwa ngasikhathi sinye zizokhuphula i-viscosity ye-MF resin futhi zinciphise ukugcwala kwe-resin, ngaleyo ndlela kuthinte ukusebenza kokufakwa kwe-MF resin. Sithole ukuthi i-viscosity ye-MF resin iyanda ngokunyuka kwenani le-nano-SiO2 (HTSi-03) yokugcwalisa ukumelana nokugqoka. I-viscosity yesistimu ye-resin ye-MF eguquliwe yayiyi-20.9 s (25 ° C), futhi i-engeli yokuxhumana phakathi kwe-resin ye-MF nephepha lokuhlobisa lenyuke lisuka ku-5 ° laya ku-30 °. Ngesikhathi esifanayo, ukumanzisa kunciphisa, ukuze i-resin ye-MF ingakwazi ukugcwalisa ngokuphelele izikhala ephepheni lokuhlobisa, futhi ukugqoka okungahambisani nokugqoka akukwazi ukukuvikela ngokugcwele, okuholela ekunciphiseni kokumelana nokugqoka.
Izinga eliphansi lokuphola langaphambi kokuphola le-MF resin lizodala ukuguquguquka okukhulu phakathi nenqubo ye-veneer, okubangele izimbali ezimanzi ezingaphezulu zibe nomthelela ekusebenzeni kwendawo. Izishintshi zotshwala ze-Polyhydroxyl zingakhuphula ngempumelelo ukuguquguquka kwenhlaka ye-MF, kodwa i-hydrophilicity ethile yezishintshi ze-polyhydroxyl ayihambisani nokomiswa kwephepha lefilimu elinamathelayo elifakwe ngaphakathi, ngaleyo ndlela kwehlise izinga lokuphulukiswa kwangaphambili kweresin ye-MF. Lokhu kubangela izinkinga ezifana nokumuncwa komswakama nokunamathela kwephepha lefilimu elinamathelayo elifakwe ngaphakathi kanye nobunzima bokufinyelela. Ngesikhathi esifanayo, iphepha lefilimu elinamathiselwe elihlanganisiwe elinezinga eliphansi lokuphulukisa ngaphambi kwesikhathi lizokhipha amanzi amaningi ngesikhathi sokucindezela okushisayo, okubangela izinkinga ezifana nokuncipha kwevolumu yengqimba yokunamathisela nokuqhekeka kwesendlalelo se-resin, okuthinta ukusebenza komkhiqizo.
Ngakho-ke, uma kucatshangelwa izinkinga zangempela zokukhiqiza, i-ejenti ye-MF resin toughening esetshenziselwa ukumiliselwa kufanele isebenzise isilungisi esinesisindo esiphansi samangqamuzana, okuqukethwe kwe-hydroxyl ephansi, nokusebenza kabusha okuphezulu ukuze kuncishiswe umthelela wesilungisi ku-fluidity nedigri yokuphulukisa ngaphambili kweresin ye-MF. Ngasikhathi sinye, i-ejenti eqinisayo iyadingeka ukuthi ivumelane nezimo zokuphulukisa ze-MF resin esetshenziselwa ukukhulelwa, futhi isalondoloze umphumela wokuguqula ngemuva kokuphulukiswa kokucindezela okushisayo.
Ukuguqulwa kwe-MF resin yokukhulelwa kudinga ukucabangela izici eziningi ngesikhathi esisodwa. Isilungisi esifanelekile sizothuthukisa ukuguquguquka kwe-MF resin ngaphandle kokuthikameze kabi ukumelana nokugqokwa kwendawo, uketshezi noma inqubo yokwelapha ngaphambilini. Ngakho-ke, kunconywa ukuthi ucwaningo lwesikhathi esizayo mayelana nokuguqulwa kwe-MF resin kufanele lwenziwe kusukela kulezi zici ezintathu ezilandelayo.
1) Ngokusekelwe esakhiweni se-MF resin, inkinga ye-brittleness ye-MF resin ingaxazululwa ngokulungisa ukuminyana kokuxhumanisa kwe-MF resin.
2) Ukuhlanganisa izindlela ezihlukene eziqinisayo, wethula ukwakheka kweketango eliguquguqukayo elinamaqembu anemisebenzi eminingi ku-resin ye-MF, futhi kwandise ukuguquguquka kwe-resin ye-MF ngokusebenzisa i-synergy yenhlanganisela yomzimba nokusabela kwamakhemikhali.
3) Ngokombono wokwenza lula inqubo yokukhiqiza kanye nezindleko zokonga, khetha izilungisi ezisebenza kahle kakhulu ezifanele ukukhiqizwa kwezimboni.
Ulwazi olwengeziwe mayelana ne-SINOYQX modified melamine formaldehyde resin, sicela usithinte nge-imeyili: [email protected] , noma usithumelele izwi ku: +86-28-8411-1861.
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