Yini engqondisa ukuba i-polyurethane iyagcinwa ngokuchemikhali? Ngokubaluleka kakhulu kuhlobene nale ndlela amaphakathi aqondakalayo. Ngokwezifiso, le nto yindlela ephakathi kwezinye izici ezibangelwa kanye nezinye ezikhangelwa, futhi le ndlela ithina ukuba yindlela elula futhi inamandla lapho kudingeka. Le ngxenzo ye-urethane esiyini ngaso sonke isigaba siyathatha indlela yamakhanda amakhulu angavikeli lapho ekhishwa kuma-chemicals amaningi. Abasebenzisa amagunya amathiphu wokwenza ukwenza ubudlelwane phakathi kwezi zici ezibangelwa kanye nezikhangelwa, lokhu kuvumela abasebenzisa ukwenza izinhlobo zika-polyurethane ezingathutha ngokulungile kuma-solvents futhi noma amakhemikhali amanye. Ngokuba yile ndlela ethulwana, izinkampani ezahlukahlukene ezifakwa kwezokweyisa amandla kanye nezokwenza izinto ezidinga ukuba zilungile kuma-chemicals amaningi ngeke zikhathaze ngemva kokuba zilahle.
Okunye ukwenzakalelo olunciphisa indlela embangela polyurethanes ikhokhise imikhawulo ngokuchaza ngokuthi yini enguqulwa ngokuphakathi. Ngokwesibonelo, lokhu kusho ukuthi kudale isihlanhla se-3D ngaso sonke isithwekisi, sokwenza kube ngemvunulo ngokwehlisa imikhawulo embi. Kunezindlela eziningi abasebenzisa kuzwa ukufikelela kule nkqubo yokuguqulwa ngokuphakathi. Abanye bavamele ukusebenzisa ukulinda ngenkqubo yemvula, abanye bongena ngemikhawulo yisicelo noma bavame ukusebenzisa izililo ngokulandela ukudalwa. Umnwe wokusebenzisa kunezinhlobo ezahlukene zokuphela kwezimkhawulo. Imicabango engamaqondana nezinhlobo ezahlukene zombuso ibonisa ngqo ukuthi izinto neziguquko eziphezulu ziphepha ngempela kwezimkhawulo eziphambene njengokulinda nezililo. Kwezinto ezithintekayo ngokuphelele kulezi zinto, ukuguqulwa okuphakathi kwenza umba ngokuphela kweyiphi indlela bayaqala ukulahla kakhulu kumaphakamiso embi.
Ukuphumelela kwezinkhamba zokwenza polyurethane kuthathwa isithupa lapho kuthiwa kumaqondo amanye amakhemikhali awuqukethe amakhethane, izibhakabhaka kanye nezinhlanhla. Izivivinywa ezigcwele kubonisa ukuthi lezi zinhlobo zokwenza ziyaphumelela kangakanani kuhlanganisa noma yikuphi ikhethane lapho kuthiwa kuye. Ngokwesibonelo, izinhlobo eziningi zokwenza polyurethane ziyaphumelela ngokujulile kanye nezikhethane nezinhlanhla ezithile kodwa zikhathaza kakhulu lapho zithiwa kumaqondo amakhemikhali amakhulu ngemva kalo. Lezi zinhlobo zokwenza ayaphakelwa lapho kuthiwa kumaqondo amakhemikhali amakhulu ngemva kalo. Ngakho ke kubaluleke ukuthi ukhethe uhlobo lwokwenza polyurethane olufanele lapho kuthiwa kumqondo wekhethane oludingekayo. Ukwenza oku kusikhokhe ukuthi kuthathe isithupa kanye nokuba izinkhamba zokwenza ziyasebenza ngokujulile kakhulu ngemva kalo.
Ukuguqula kwezinkelosi kanye nezimo zokudwelwa zinhloso kakhulu kanjani i-polyurethane isikwe engqikweni. Lapho izinkelo ziphezulu, le nto ihlanganisa kuhlanga lwesikwe, okungathi kuzokungcola kanjani ukuthi isikwe siyathola ngokwelapha lapho kuthiwa ngemikhawulo engqikweni ngokudlule kwesikhathi. Izimo zokudwelwa zinezinkimbinkimbi futhi. Izinhlobo zokugcina kanye nezinkimba zika-UV esibonelweni zokulwa zihlasela amagugu e-polyurethane kakhulu kunezidinga. Ukubheka ukuthini kusalela kwezemvelo kumaphakathi wokwenza izinto kubiningi bezindlela kuboniswe ukuthi ukugcina izinto kakhulu nezimo zokudwelwa kungaba yisici esisodwa sokuthi i-polyurethane iphumelele ngokude. Kumaqhamani owenziwa nezinto eziphathwe ngokweqile e-polyurethane, ukulawula lezi zimo zokudwelwa akuyona kuphela okungcono kodwa yimpiyeki yokuthola ukusebenza okuphezulu kwezinjani zabo.
Lokhu lasebenza nezinhlayiya zokuxhumana ne-acid, ukusebenza kwe-polyurethane kubaluleke kakhulu. Uma izinto zahamba awuqondile kule meko, izinhlangano ngokwengeza ukuphantsi okukhulu nokulungiswa okuvimba izindleko. Ngokwesimo esikhona sengingili yabaqaphela ngeminyaka, ukudala i-polyurethane kumathini apho kusetshenziselwa amakhemikhali amaningi kungenzeka ukuthi kwenze amaphethini aphila ngokude. Abaningi abasebenzini bokuthi uma usebenzisa izinhlobo eziphambene ne-polyurethane nezinhlayiya zokuxhumana nezakhemikhali ezintsha, ukusunguka kwezinhlayiya ngokuphelele kwezokuxhumana nezikhathazo kungcono. Lokhu kwenza ukusebenza kuhlale kuhlanganise ngokuzwakile ngaphandle kokulindela ukulungiswa ngokuyiminyaka.
Imi standadhi ye-ASTM kanye ne-ISO uyaphandle kweqo xa kuchazwa indlela abekeleke kahle izinto njenge-polyurethane ngokuxhuma neezimbanzi. Le standadhi zinikeza imidlalo ephambene ngokwesemantiko ukuze bonke bafumane imiphumela embalwa xa bahlola. Ngenkathi yehlolwa ngokwephakathi, izinto zokuhlola ziqoshelwa kwiizimbanzi ezahlukene kwiindlela zokuhlola ezingaphandle kwezinto ngokwengqondo. Xa ababhuyekelele bafollowa le mi standadhi yokuhlola, bafumana amanani amathathwa okunikezela inkqubo yabo kwaye enzeke abathengi bazi kahle ukuba yintoni iqhutywa lokusebenza kwezinto. Le hlolwa ngokupheleleyo ayiyiyo kuphela umsebenzi othandwayo kodwa yinto efunekayo ukuze kugcinwe ubunzima obuphakeme kwiindlela zokubhuyekelela zazo zonke izinto.
Ukucacisa izinombolo zokwenjiniwe kumaqondo we-ASTM nokwe-ISO kuyindlela ebalulekile ukuthola amagugu afanele ukuthi ayilinde isimo esikhundleni. Oku kuchaze ukuthini kumele kumele kuchazwe ngokuchasene nezindlela ezifanako nezinhlobo zokugcina (tensile strength), ukuthini kumele kube yilapho ukuthini kumele kube yilapho ukuthini kumele kube yilapho ukuthini kumele kube yilapho (elongation at break), futhi ukuthi kuyilapho oku kumele kube yilapho kumaqondo ethile. Abasebenzisa lezi zici kufanele bazi ukuthi lezi zici zingasimama kanjani. Isibonelo, amakhampani okwenza izilinda zokwenjini kumele aqondise lezi zici ngoba ahlule ukuthi lezi zilinda zingasebenza ngeminyaka engaphansi kwezimo ezithintekayo. Uma abasebenzisa azi ukuthini lezi zinombolo zingasembenza, kungasebenzelwa ukuthi lezi zici zingasebenza ngemva kwenyanga nekwehlo, noma emaphakathini apho izimo eziphambene nezimo zokusebenza ziyindlela ebalulekile yokusebenza.
Ukuphapha kunezindlela zokuthi ukuthambekile, kodwa xa kufika kokuqiniseka kwezilindelekile, ipoliuyithayeni yindlela enye iyavuma, ngakumbi emaphakamathini amakhanda. Izivivinyo ehlukanisa lezi zinhlobo zonke zibonisa ukuthi ipoliuyithayeni ingasebenzi ngokuholela kakhulu futhi ingasebenzi ngokuthululwa, lokhu kwenza yinto efanayo nezindlela zokulayela noma izilayela emaphakamathini aphakamayo lapho izindlela zokulayela zingasebenzi ngokuthululwa. Izinombolo zinezinye izindlela zokuthi amaphakamathi amaningi aqala ukusebenzisa ipoliuyithayeni ngenkathi ingasebenzi ngokudla futhi ingasebenzi ngokuthululwa. Futhi yekelani, akukho muntu othanda ukubuya izinto yonke iminyaka emibili. Izinkampani zilalela izindlela zokuthi zingasebenzisa izinto zokulayela ngokuthululwa noma zilalela izindlela zokuthi zingasebenzisa izinto ezifiswe ngokuthululwa.
Imali ephakathi kahle lula kancane xa kuthiwe ngemikhawulo ephunzeka ngokukhawuleza, kepha i-polyurethane iyahlaka ngempumelelo ngaphezulu kule meqo. Izifundo zibonisa ukuthi ukudala amagqabi apholile kankulu ngaphakathi kwamatanki noma kwemikhawulo etholakala ngemikhawulo ephunzeka kungakhathazisa ukuphila kwemali ekugcineni ngezinyaka, kubonisa iziphamela ukuthi kungakhethiwe ukulungiswa okuphakeme emuva. Abasebenzi bemjengo becomba ukuthi bawelwe imali ngezindawo zokudonsa polyurethane esingathi kutholakale ngokungodwa. I-metal iyahlala inqubo yamandla ngelokho i-polyurethane isebenza njengokugcisa okuphunzeka. Le kombisa isebenza kahle kumaqondo ezenzakalo apho izinhlelo zidinga ukutholakala kwezinyathelo eziningi nezikhathi eziningi.
Ukuthuthukiswa phakathi kwezimaterialu kufanele uqonde izidingo eziyinkimbinkimbi zalo noma yiliphi isebenza kanye nokukhetha umaterialo onemiphumo yekhono kanye nokhesho.
I-Polyurethane senziwe yinto ephumelelayo yokwenza izixhobo edinga ukulaywa kwiindawo ebonisa ukulawulwa kwegesini kunye nezinye izinto ezingaqhelekanga ngokuba yonke into enokuthula kakhulu ngokulawulwa kwegesini. Oku kuthiyla ngokuba kuthanda kakhulu xa kuchazwa indawo apho iistile okanye iingcawu zokulaywa zizakugqibela kakhulu, benze kube lula ukujonga ukuba zinzuzo ngokweNdawo. Ukuhlolwa kwasekatheni kwiindlela ezahlukeneyo zokusebenza kubonisa ngokuphindaphindayo ukuba iindlela ezinikiweyo i-Polyurethane zinzuzo kakhulu xa zilawulwa kwiigesini ezinhlekileyo kunye nezinye izinto. Ngokwezampi, kwiindawo apho kusebenzwa nezinto njengegesi yasulfuric okanye isodium hydroxide solution, oku kuthiyla ngokuba kuncinane ukubuyiselwa kufuneka kwenziwe kwaye ukusebenza kwezixhobo kubu kabanzi. Le nto iyahlula ukuba yinto echanekileyo ngokuba kuzo zonke iindlela, oko kuthiyla ngokuba abasebenzisi bencinane izindleko zokulungisa kwaye bafumane ngakumbi ukuphela okungase kungeniswa kwiintsimbi zokusebenza.
Abaprofeshonali bokhangeza bakhusebenzisa ipolyurethane engenelwa ngokuchemical ngokuba iyahlukana ngempumelelo kakhulu kunezinye izinhlelo zokulinda kwekhalasi nezinhlelo zokwehluleka. Izivivinyo zokusebenza kwangaphandle kubonisa ukuthi lezi zingcindelela ziyehlisa izinhlelo eziphambene nezindlela ezinhle ezithuthukisiwe kakhulu kwezinye izihlabathi nezinhlelo eziphathelene nezimo eziphakeme kwezintaba. Kumaqo amadoni aqoqwa ngokuphelele, lokhu kuyindlela kakhulu ngokuba ukulungisa ukugcinwa futhi ukugcinwa okukhishwa yizimo kuthatha izinkimbini eziningi kwaqoqwa ngamunye. Abasebenzisi babekiwe ukuthatha amabhajethi abalulekile emuva kokuguqula kwi-polyurethane linings ngokuba yilapho iyahlukana ngempumelelo ngaphansi kwezintaba eziphakeme. Imfanelo yokhangeza ibonile lokhu kuye futhi abakhulu bezihlabathi banele ukuchaza ipolyurethane njengokuthi kuyisisekelo esingcono kwezinye izindawo eziphathelene nokulinda kwezintaba nezinhlelo zokwehluleka.
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