Lub thickener rau cov xim latex yuav tsum muaj kev sib raug zoo nrog cov emulsion polymer compound, txwv tsis pub cov zaj duab xis txheej yuav muaj me me ntawm reticulate, thiab yuav tsim irreversible particle agglomeration, uas yuav txo tau cov viscosity thiab coarsen particle loj. Lub thickener yuav hloov tus nqi ntawm emulsion. Piv txwv li, cationic thickener yuav muaj qhov cuam tshuam tsis zoo ntawm anionic emulsifier kom tawg emulsion. Lub thickener zoo tagnrho rau cov xim latex yuav tsum muaj cov khoom nram qab no:
1. Tsawg npaum li cas thiab zoo viscosity
2. Zoo cia ruaj khov, tsis muaj viscosity txo vim qhov kev ua ntawm cov enzymes, thiab tsis muaj viscosity txo vim qhov kev hloov ntawm kub thiab PH nqi
3, dej tuav tau zoo, tsis muaj qhov tshwm sim pom tseeb npuas
4. Tsis muaj kev phiv los ntawm cov khoom siv hauv zaj duab xis xws li txhuam tsis kam, gloss, zais lub zog thiab dej tsis kam
5. Tsis muaj xim flocculation
Lub tshuab thickening ntawm latex xim yog ib qho tseem ceeb ntsuas los txhim kho cov latex zoo thiab txo tus nqi. Hydroxyethyl cellulose yog ib qho zoo tagnrho thickener, uas muaj ntau yam teebmeem ntawm thickening, stabilization thiab rheological hloov ntawm latex xim.
Hauv kev tsim cov xim latex,Hydroxyethyl Cellulose (HEC)yog siv los ua dispersant, thickener thiab pigment suspending tus neeg saib xyuas kom stabilize lub viscosity ntawm cov khoom, txo agglomeration, ua rau cov xim zaj duab xis du thiab du, thiab kuj ua rau cov xim latex ntau check. Zoo rheology, tuaj yeem tiv taus siab shear zog, thiab tuaj yeem muab cov qib zoo, khawb tsis kam thiab xim xim sib xws. Nyob rau tib lub sijhawm, HEC muaj kev ua haujlwm zoo, thiab cov xim latex thickened nrog HEC muaj pseudoplasticity, yog li cov kev tsim kho xws li txhuam, dov, sau, thiab tshuaj tsuag muaj qhov zoo ntawm kev ua haujlwm-txuag, tsis yooj yim los ntxuav thiab sag, thiab tsis tshua muaj txaws. HEC muaj kev tsim kho xim zoo heev. Nws muaj cov miscibility zoo heev nrog rau feem ntau cov xim thiab cov binders, ua rau nws muaj peev xwm tsim cov xim latex nrog cov xim zoo sib xws thiab ruaj khov. Lub versatility thov nyob rau hauv lub formulation, nws yog ib tug non-ionic ether. Yog li ntawd, nws tuaj yeem siv dav hauv pH ntau yam (2 ~ 12), thiab tuaj yeem sib xyaw nrog cov khoom siv ntawm cov xim latex xws li cov xim reactive, additives, soluble salts los yog electrolytes.
Tsis muaj kev cuam tshuam rau cov yeeb yaj kiab txheej. Vim hais tias HEC aqueous tov muaj cov yam ntxwv ntawm cov dej nro, nws tsis yooj yim rau ua npuas ncauj thaum lub sij hawm tsim khoom thiab kev tsim kho, thiab qhov nyiam ntawm volcanic qhov thiab pinholes tsawg dua.
Zoo ruaj khov. Nyob rau hauv lub sij hawm ntev cia txheej txheem, lub dispersibility thiab ncua kev kawm ntawv ntawm cov xim yuav khaws cia, thiab tsis muaj teeb meem ntawm floating xim thiab blooming. Thaum muaj cov dej me me ntawm cov xim pleev xim thiab qhov chaw cia kub hloov pauv zoo heev. Nws cov viscosity tseem nyob ruaj khov.
HEC tuaj yeem nce tus nqi PVC (pigment ntim concentration) cov khoom muaj pes tsawg leeg mus txog 50-60%. Tsis tas li ntawd, topcoat thickener ntawm cov xim pleev xim dej kuj tuaj yeem siv HEC.
Tam sim no, cov thickeners siv nyob rau hauv domestic high-qib latex xim yog mas HEC thiab acrylic polymers (xws li polyacrylates, homopolymer los yog copolymer emulsion thickeners ntawm acrylic acid thiab methacrylic acid) thickeners.
Hydroxyethyl cellulose tuaj yeem siv rau
1. Raws li cov khoom tawg los yog cov kua nplaum tiv thaiv
Feem ntau, HEC nrog viscosity ntawm 10 mus rau 30 mPaS yog siv. HEC txog li 300mPa·S tuaj yeem siv ua ke nrog anionic lossis cationic surfactants, thiab cov nyhuv dispersion zoo dua. Tus nqi siv feem ntau yog 0.05% ntawm qhov loj ntawm cov monomer.
2, raws li lub thickener
Siv 15000mPa. Kev siv ntau npaum li cas ntawm high-viscosity HEC saum toj no yog 0.5 mus rau 1% ntawm tag nrho cov huab hwm coj ntawm cov latex txheej, thiab PVC tus nqi tuaj yeem ncav cuag li 60%. Hauv cov xim latex, HEC ntawm 20Pa, s yog siv, thiab ntau yam khoom ntawm cov xim latex yog qhov zoo tshaj plaws. Tus nqi tsuas yog siv HEC siab dua 30O00Pa.s qis dua. Txawm li cas los xij, cov qib thiab lwm yam ntxwv ntawm cov xim latex tsis zoo. Los ntawm qhov kev xav ntawm kev xav tau zoo thiab txo tus nqi, nws yog qhov zoo tshaj plaws los siv nruab nrab thiab siab viscosity HEC ua ke.
3. Txoj kev sib xyaw ua ke hauv cov xim latex
Nto kho HEC tuaj yeem muab ntxiv rau hauv cov hmoov qhuav lossis slurry daim ntawv. Cov hmoov qhuav yog ncaj qha ntxiv rau cov xim sib tsoo. Qhov pH ntawm qhov sib ntxiv yuav tsum yog 7 lossis qis dua. Alkaline Cheebtsam xws li dispersants tuaj yeem ntxiv tom qab lubHECtau wetted thiab tag nrho dispersed. Slurry ua nrog HEC yuav tsum tau muab sib xyaw rau hauv slurry ua ntej HEC tau muaj sijhawm txaus los hydrate thiab thickened mus rau ib qho kev siv tsis tau. HEC slurries kuj tuaj yeem npaj nrog glycol-based coalescing agents.
4. Anti-mildew ntawm latex xim
Dej-soluble HEC biodegrades thaum raug pwm uas tshwj xeeb rau cellulose thiab nws cov derivatives. Ntxiv preservatives rau xim ib leeg tsis txaus, tag nrho cov khoom yuav tsum tsis muaj enzyme. Cov tsheb tsim cov xim latex yuav tsum tau ua kom huv si thiab huv si, thiab txhua yam khoom siv yuav tsum tau ua kom tsis tu ncua nrog chav 0.5% formalin lossis 0.1% mercury tov.
Lub sij hawm xa tuaj: Plaub Hlis-25-2024