Thickeners rau cov xim latex yuav tsum muaj kev sib raug zoo nrog cov latex polymer tebchaw, txwv tsis pub yuav muaj me me ntawm kev ntxhib los mos hauv cov zaj duab xis txheej, thiab qhov tsis tuaj yeem sib sau ua ke yuav tshwm sim, ua rau txo qis viscosity thiab coarser particle loj.Thickeners yuav hloov tus nqi ntawm emulsion.Piv txwv li, cationic thickeners yuav muaj cov nyhuv irreversible ntawm anionic emulsifiers thiab ua rau demulsification.Ib qho zoo tagnrho latex xim thickener yuav tsum muaj cov khoom nram qab no:
1. Tsawg npaum li cas thiab zoo viscosity
2. Zoo cia ruaj khov, yuav tsis txo cov viscosity vim qhov kev ua ntawm cov enzymes, thiab yuav tsis txo cov viscosity vim qhov kev hloov ntawm kub thiab pH nqi.
3. Cov dej tuav tau zoo, tsis muaj qhov pom tseeb ntawm huab cua npuas
4. Tsis muaj kev phiv rau cov xim zaj duab xis xws li txhuam tsis kam, gloss, zais lub zog thiab dej tsis kam
5. Tsis muaj flocculation ntawm pigments
Lub tshuab thickening ntawm latex xim yog ib qho tseem ceeb ntsuas los txhim kho cov latex zoo thiab txo cov nqi.Hydroxyethyl cellulose yog ib qho zoo tagnrho thickener, uas muaj ntau yam teebmeem ntawm thickening, stabilization thiab rheological hloov ntawm latex xim.
Nyob rau hauv cov txheej txheem ntawm 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 ua rau cov xim latex ntau ruaj. .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 txhuam, dov, sau, txau thiab lwm yam kev tsim kho muaj qhov zoo ntawm kev ua haujlwm txuag, tsis yooj yim kom tshem tawm, sag, thiab tsis tshua muaj txaws.HEC muaj kev txhim kho xim zoo heev.Nws muaj cov miscibility zoo heev rau feem ntau cov xim thiab cov binders, uas ua rau cov xim latex muaj xim zoo sib xws thiab ruaj khov.Versatility rau daim ntawv thov nyob rau hauv formulations, nws yog ib tug non-ionic ether.Yog li ntawd, nws tuaj yeem siv dav hauv pH ntau (2 ~ 12), thiab tuaj yeem sib xyaw nrog cov khoom siv hauv cov xim pleev xim xws li cov xim reactive, additives, soluble salts lossis electrolytes.
Tsis muaj qhov cuam tshuam tsis zoo ntawm txheej yeeb yaj kiab, vim hais tias cov tsiaj aqueque muaj qhov yooj yim rau ua npuas ncauj, thiab qhov nyiam ntawm roob hluav taws xob thiab pinholes yog tsawg dua.
Zoo ruaj khov.Thaum lub sij hawm ntev cia, qhov dispersibility thiab ncua ntawm cov xim tuaj yeem khaws cia, thiab tsis muaj teeb meem ntawm ntab xim thiab tawg paj.Muaj cov txheej dej me me ntawm cov xim pleev xim, thiab thaum khaws 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 txog li 50-60%.Tsis tas li ntawd, cov txheej txheej txheej thickener ntawm cov xim dej tuaj yeem siv HEC.
Tam sim no, cov thickeners siv nyob rau hauv domestic nruab nrab thiab qib high-qib latex xim yog imported HEC thiab acrylic polymer (xws li polyacrylate, 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 10-30mPaS yog siv.HEC uas tuaj yeem siv tau txog li 300mPa·S yuav muaj qhov cuam tshuam zoo dua yog tias nws siv nrog anionic lossis cationic surfactants.Kev siv ntau npaum li cas feem ntau yog 0.05% ntawm monomer loj.
2. Raws li lub thickener
Siv 15000mPa.Kev siv ntau npaum li cas ntawm cov viscosity HEC saum toj no yog 0.5-1% ntawm tag nrho cov xim ntawm cov xim, thiab PVC tus nqi tuaj yeem ncav cuag li 60%.Siv HEC txog 20Pa, s hauv cov xim latex, thiab kev ua haujlwm 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 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 dua los siv nruab nrab thiab siab viscosity HEC ua ke.
3. Txoj kev sib xyaw hauv cov xim latex
Nto kho HEC tuaj yeem muab ntxiv rau hauv cov hmoov qhuav lossis muab tshuaj txhuam.Cov hmoov qhuav yog ntxiv ncaj qha rau cov pigment grind.Cov pH ntawm qhov chaw pub noj yuav tsum yog 7 lossis qis dua.Alkaline Cheebtsam xws li Yanbian dispersant tuaj yeem muab ntxiv tom qab HEC tau ntub thiab tawg tag nrho.Slurries ua nrog HEC yuav tsum tau muab sib xyaw rau hauv cov slurry ua ntej HEC tau muaj sijhawm txaus los hydrate thiab cia kom thicken mus rau qhov siv tsis tau.Nws tseem tuaj yeem npaj HEC pulp nrog ethylene glycol coalescing agents.
4. Anti-pwm ntawm latex xim
Dej-soluble HEC yuav biodegrade thaum nyob rau hauv kev sib cuag nrog pwm uas muaj tshwj xeeb los ntawm cellulose thiab nws derivatives.Nws tsis txaus los ntxiv cov tshuaj tua kab mob rau cov xim ib leeg, tag nrho cov khoom yuav tsum tsis muaj enzyme.Lub tsheb tsim cov xim latex yuav tsum tau ua kom huv si, thiab txhua yam khoom siv yuav tsum tau ua kom tsis tu ncua nrog chav 0.5% formalin lossis O.1% mercury tov.
Post lub sij hawm: Dec-26-2022