Izithisi zopende we-latex kumele zivumelane kahle nama-compound e-latex polymer, ngaphandle kwalokho kuzoba khona inani elincane lokuthungwa efilimini yokumboza, futhi kuzokwenzeka ukuhlanganiswa kwezinhlayiya ezingenakuguqulwa, okuholela ekunciphiseni kwe-viscosity kanye nosayizi wezinhlayiya eziqinile. Izithisi zizoshintsha ukushaja kwe-emulsion. Isibonelo, izithisi ze-cationic zizoba nomthelela ongenakuguqulwa kuma-emulsifier e-anionic futhi zibangele i-demulsification. Isithisi sopende we-latex esifanele kumele sibe nezakhiwo ezilandelayo:
1. Isilinganiso esiphansi kanye nokuthamba okuhle
2. Ukuqina okuhle kwesitoreji, ngeke kunciphise i-viscosity ngenxa yesenzo sama-enzyme, futhi ngeke kunciphise i-viscosity ngenxa yezinguquko ekushiseni kanye nenani le-pH
3. Ukugcinwa kwamanzi okuhle, akukho amabhamuza omoya asobala
4. Akukho miphumela emibi ezimpahleni zefilimu yopende njengokumelana nokukhuhla, ukucwebezela, amandla okufihla kanye nokumelana namanzi
5. Akukho ukugoqana kwezinhlayiya
Ubuchwepheshe bokujiya kopende we-latex buyindlela ebalulekile yokuthuthukisa ikhwalithi ye-latex nokunciphisa izindleko. I-Hydroxyethyl cellulose iyisithako esifanelekile, esinemiphumela eminingi ekusebenzeni kokuqina, ukuzinza kanye nokulungiswa kwe-rheological kopende we-latex.
Enqubweni yokukhiqiza upende we-latex, i-hydroxyethyl cellulose (HEC) isetshenziswa njenge-dispersant, thickener kanye ne-pigment suspension agent ukuze kuqiniswe i-viscosity yomkhiqizo, kuncishiswe i-agglomeration, kwenziwe ifilimu yopende ibe bushelelezi futhi ibushelelezi, futhi kwenziwe upende we-latex uhlale isikhathi eside. I-rheology enhle, ingamelana namandla aphezulu okucheba, futhi inganikeza ukuleveli okuhle, ukumelana nokuklwebheka kanye nokufana kombala. Ngesikhathi esifanayo, i-HEC inamandla okusebenza kahle kakhulu, kanti upende we-latex oqiniswe nge-HEC unama-pseudoplasticity, ngakho-ke ukuxubha, ukugoqa, ukugcwalisa, ukufutha kanye nezinye izindlela zokwakha kunezinzuzo zokonga abasebenzi, akulula ukuwususa, ukugoba, kanye nokuchaphaza okuncane. I-HEC inokuthuthukiswa kombala okuhle kakhulu. Inokuguquguquka okuhle kakhulu kwezinhlobo eziningi zombala kanye nezihlanganisi, okwenza upende we-latex ube nokuvumelana okuhle kombala kanye nokuzinza. Ukuguquguquka kokusetshenziswa ekwakhiweni, kuyi-ether engeyona i-ionic. Ngakho-ke, ingasetshenziswa ebangeni elibanzi le-pH (2 ~ 12), futhi ingaxutshwa nezingxenye ezipendwe ngopende we-latex ojwayelekile njengemibala ephendulayo, izithasiselo, usawoti oncibilikayo noma ama-electrolyte.
Akukho mphumela omubi efilimini yokumboza, ngoba isixazululo samanzi se-HEC sinezici ezicacile zokuxineka kwamanzi, akulula ukusenza sibe negwebu ngesikhathi sokukhiqiza nokwakha, futhi ukuthambekela kwemigodi yentaba-mlilo kanye nemigodi emincane kuncane.
Ukuqina okuhle kokugcina. Ngesikhathi sokugcina isikhathi eside, ukuhlakazeka nokumiswa kombala kungagcinwa, futhi akukho nkinga yombala ontantayo nokuqhakaza. Kukhona ungqimba lwamanzi oluncane ebusweni bopende, futhi lapho izinga lokushisa lokugcina lishintsha kakhulu. Ukuqina kwawo kusazinzile.
I-HEC ingakhuphula inani le-PVC (ukuhlushwa kwevolumu ye-pigment) ukwakheka okuqinile kufikela ku-50-60%. Ngaphezu kwalokho, isithambisi sokugqoka ubuso sopende osekelwe emanzini singasebenzisa ne-HEC.
Njengamanje, izithisi ezisetshenziswa kupende we-latex wasekhaya ophakathi nendawo kanye nowezinga eliphezulu zingeniswa yi-HEC kanye ne-acrylic polymer (kufaka phakathi izithisisi ze-polyacrylate, i-homopolymer noma i-copolymer emulsion ze-acrylic acid kanye ne-methacrylic acid).
I-Hydroxyethyl cellulose ingasetshenziswa
1. Njenge-dispersant noma i-glue evikelayo
Ngokuvamile, kusetshenziswa i-HEC ene-viscosity engu-10-30mPaS. I-HEC engasetshenziswa kufika ku-300mPa·S izoba nomphumela wokusabalala ongcono uma isetshenziswa kanye nama-surfactants e-anionic noma e-cationic. Isilinganiso sokubhekisela ngokuvamile siyi-0.05% yesisindo se-monomer.
2. Njengesithambisi
Sebenzisa i-15000mPa. Isilinganiso sokubhekisela se-HEC ene-viscosity ephezulu ngaphezu kwe-s singu-0.5-1% wesisindo esiphelele sopende we-latex, kanti inani le-PVC lingafinyelela cishe ku-60%. Sebenzisa i-HEC engaba ngu-20Pa,s kupende we-latex, futhi ukusebenza kopende we-latex kungcono kakhulu. Izindleko zokusebenzisa nje i-HEC engaphezu kwama-30O00Pa.s ziphansi. Kodwa-ke, izakhiwo zokulinganisa zopende we-latex azilungile. Ngokombono wezidingo zekhwalithi kanye nokunciphisa izindleko, kungcono ukusebenzisa i-HEC ene-viscosity ephakathi nephezulu ndawonye.
3. Indlela yokuxuba upende we-latex
I-HEC ehlungiwe ngaphezulu ingafakwa ngempuphu eyomile noma ngesimo sokunamathisela. Impuphu eyomile ifakwa ngqo ku-pigment grind. I-pH endaweni yokudla kufanele ibe ngu-7 noma ngaphansi. Izingxenye ze-alkaline ezifana ne-Yanbian dispersant zingafakwa ngemva kokuba i-HEC imanzisiwe futhi ihlakazeke ngokuphelele. Ama-slurry enziwe nge-HEC kufanele ahlanganiswe ne-slurry ngaphambi kokuba i-HEC ibe nesikhathi esanele sokumanzisa futhi ivumele ukuthi iqine ibe sesimweni esingasetshenziswa. Kungenzeka futhi ukulungiselela i-pulp ye-HEC ngama-ethylene glycol coalescing agents.
4. Upende we-latex omelene nokubumba
I-HEC encibilika emanzini izobola uma ithintana nezikhunta ezinemiphumela ekhethekile ku-cellulose kanye nezinto eziphuma kuyo. Akwanele ukwengeza izithasiselo kupende kuphela, zonke izingxenye kumele zingabi nama-enzyme. Isithuthi sokukhiqiza upende we-latex kumele sigcinwe sihlanzekile, futhi yonke imishini kumele ihlanzwe njalo ngesisombululo se-0.5% formalin noma i-O.1% mercury
Isikhathi sokuthunyelwe: Disemba-26-2022