Kugira ngo bakemure ikibazo cy’uko irangi risanzwe rya polyurethane rishobora kwangirika kandi ridafite ubushobozi bwo kwivura, abashakashatsi bakoze irangi rya polyurethane rishobora kwivura rifite 5 wt% na 10 wt% by’imiti ivura binyuze mu buryo bwa Diels-Alder (DA) cycloaddition. Ibisubizo bigaragaza ko gushyiramo imiti ivura byongera ubukana bwa 3%–12% kandi bigatuma gukira neza kwa 85.6%–93.6% mu minota 30 kuri 120 °C, bikongera cyane igihe cyo gukora irangi. Ubu bushakashatsi butanga igisubizo gishya cyo kurinda ubuso bw’ibikoresho by’ubuhanga.
Mu rwego rw'ibikoresho by'ubuhanga, gusana ibyangiritse mu bikoresho byo gusiga byari imbogamizi ikomeye kuva kera. Nubwo irangi rya polyurethane risanzwe rigaragaza ubushobozi bwo guhangana n'ikirere no gufatana neza, imikorere yaryo yo kurinda iragabanuka vuba iyo habayeho gushwanyagurika cyangwa kwangirika. Bashingiye ku buryo bw'ibinyabuzima bwo kwivura, abahanga batangiye gushakisha ibikoresho byo kwivura bishingiye ku migozi ihindagurika, aho Diels-Alder (DA) yitabwaho cyane bitewe n'imiterere yayo yoroheje yo kwivura no gusubira inyuma. Ariko, ubushakashatsi buriho bwibanze cyane cyane kuri sisitemu ya polyurethane igororotse, isiga icyuho mu inyigo y'imiterere yo kwivura mu irangi rya polyurethane ivanze.
Kugira ngo bace iyi mbogamizi ya tekiniki, abashakashatsi bo mu gihugu bashyize mu buryo bushya imiti ibiri ivura indwara ya DA—furan-maleic anhydride na furan-bismaleimide—mu buryo bwa hydroxylated polyester resin, bakora irangi rya polyurethane powder rifite ubushobozi bwiza bwo kwivura. Ubushakashatsi bwakoresheje ¹H NMR kugira ngo bwemeze imiterere y’imiti ivura, differential scanning calorimetry (DSC) kugira ngo bemeze ko DA/retro-DA reactions zishobora gusubira inyuma, na nanoindentation tekiniki hamwe na surface profilometry kugira ngo basuzume neza imiterere ya mekanike n’imiterere y’ubuso bw’imiti.
Ku bijyanye n'ubuhanga bw'ingenzi bwo kugerageza, itsinda ry'abashakashatsi ryabanje gukora imiti ivura ya DA irimo hydroxyl hakoreshejwe uburyo bw'intambwe ebyiri. Nyuma yaho, ifu ya polyurethane irimo imiti ivura ya 5 wt% na 10 wt% yateguwe binyuze mu kuvanga ibintu bishongeshejwe, hanyuma ishyirwa ku byuma hakoreshejwe electrostatic spray. Mu kugereranya n'amatsinda yo kugenzura adafite imiti ivura, ingaruka z'ubwinshi bw'imiti ivura ku miterere y'ibikoresho zasuzumwe neza.
1.Isesengura rya NMR ryemeza imiterere y'ibikoresho bivura
1 H NMR spectra yagaragaje ko amine-inserted furan-maleic anhydride (HA-1) yagaragaje DA ring peaks kuri δ = 3.07 ppm na 5.78 ppm, mu gihe furan-bismaleimide adduct (HA-2) yagaragaje ikimenyetso gisanzwe cya DA bond proton kuri δ = 4.69 ppm, byemeza ko imiti ikiza yakozwe neza.
2.DSC yagaragaje imiterere ishobora guhinduka mu bushyuhe
Imirongo ya DSC yagaragaje ko ingero zirimo imiti ivura zagaragaje uburebure bwa endothermic bwa DA kuri 75 °C n'uburebure budasanzwe bwa retro-DA bwagaragaje hagati ya 110–160 °C. Agace k'uburebure kiyongereye bitewe n'ubwinshi bw'imiti ivura, bigaragaza ubushobozi bwiza bwo gusubira inyuma kw'ubushyuhe.
3.Ibizamini bya Nanoindentation byerekana ko ubukomere bwarushijeho kwiyongera
Ibizamini bya nanoindentation by’ubujyakuzimu byagaragaje ko kongeramo 5 wt% na 10 wt% by’imiti ivura byongereye ubukana bwo gutwikiraho ku kigero cya 3% na 12%, uko bikurikirana. Agaciro k’ubukana bwa 0.227 GPa kagumyeho ndetse no ku bujyakuzimu bwa 8500 nm, bitewe n’umuyoboro uhuza wakozwe hagati y’imiti ivura na polyurethane matrix.
4.Isesengura ry'imiterere y'ubuso
Ibizamini by’ubukana bw’ubuso byagaragaje ko irangi rya polyurethane ryihariye ryagabanyije agaciro ka Rz ku kigero cya 86%, mu gihe irangi rifite imiti ivura ryagaragaje ukwiyongera gato k’ubukana bitewe no kuba hari uduce duto. Amashusho ya FESEM agaragaza impinduka mu miterere y’ubuso zikomoka ku duce tw’imiti ivura.
5.Iterambere mu Gukoresha Imiti Ivura Gupfuka Umusatsi
Isuzuma rya mikorosikopi y'amaso ryagaragaje ko irangi ririmo 10 wt% by'umuti ukiza, nyuma yo kuvurwa ubushyuhe kuri 120 °C mu gihe cy'iminota 30, ryagaragaje kugabanuka k'ubugari bw'umukara kuva kuri 141 μm kugera kuri 9 μm, rigera ku bushobozi bwo gukira bwa 93.6%. Iyi mikorere iraruta cyane iyavuzwe mu nyandiko zisanzwe zikoreshwa kuri sisitemu ya polyurethane igororotse.
Iyi nyigo yasohotse muri Next Materials, itanga udushya twinshi: Ubwa mbere, irangi rya polyurethane ryahinduwe na DA rihuza imiterere myiza ya mekanike n'ubushobozi bwo kwivura, rigera ku kunoza ubukana bwa 12%. Icya kabiri, ikoreshwa ry'ikoranabuhanga ryo gutera imiti rituma habaho gukwirakwira kw'ibikoresho bivura mu buryo bumwe mu miyoboro ihuza, bigatsinda uburyo butari bwo bwo gushyira ibintu mu mwanya wabyo ku bushyuhe buri hasi (120 °C), bitanga ubushobozi bwo gukoresha mu nganda ugereranije n'ubushyuhe bwo kwivura bwa 145 °C buvugwa mu nyandiko zisanzwe. Ubu bushakashatsi ntibutanga gusa uburyo bushya bwo kongera igihe cyo gukora irangi ry'ubuhanga ariko bunashyiraho urwego rw'inyigisho ku miterere ya molekile y'irangi ry'imikorere binyuze mu isesengura ryayo ry'umubare w'isano "y'itsinda ry'ibikoresho bivura - imikorere". Guteza imbere hydroxyl mu bikoresho bivura mu gihe kizaza ndetse n'ikigereranyo cya uretdione cross-linkers byitezweho kuzamura imipaka y'irangi rivura mu buryo bwikora.
Igihe cyo kohereza ubutumwa: 15 Nzeri 2025