xov xwm

Vim tias qhov viscosity ntawm cov dej-raws li resin qis heev, nws tsis tuaj yeem ua tau raws li qhov xav tau ntawm kev khaws cia thiab kev tsim kho ntawm cov txheej, yog li nws yog qhov tsim nyog los siv cov thickener tsim nyog los kho qhov viscosity ntawm cov dej-raws li txheej rau lub xeev raug.

Muaj ntau hom thickeners. Thaum xaiv cov thickeners, ntxiv rau lawv cov thickening efficiency thiab kev tswj hwm ntawm cov txheej rheology, qee yam lwm yam yuav tsum tau xav txog kom ua rau cov txheej muaj kev ua tau zoo tshaj plaws, cov yeeb yaj kiab txheej zoo tshaj plaws thiab lub neej ua haujlwm ntev tshaj plaws.

Kev xaiv cov hom thickener feem ntau yog raws li qhov xav tau thiab qhov xwm txheej tiag tiag ntawm cov qauv.

Thaum xaiv thiab siv cov thickeners, cov no yog qhov tseem ceeb.

1. HEC uas muaj qhov hnyav molecular siab muaj qhov sib txuas ntau dua piv rau qhov hnyav molecular qis thiab ua kom pom tseeb tias nws tuab dua thaum khaws cia. Thiab thaum tus nqi shear nce ntxiv, lub xeev winding raug rhuav tshem, tus nqi shear ntau dua, qhov cuam tshuam ntawm qhov hnyav molecular ntawm viscosity me dua. Lub tshuab thickening no tsis muaj dab tsi ua nrog cov khoom siv hauv paus, cov xim thiab cov khoom siv ntxiv, tsuas yog yuav tsum xaiv qhov hnyav molecular ntawm cellulose thiab kho qhov concentration ntawm thickener tuaj yeem tau txais qhov viscosity zoo, thiab yog li siv dav.

2. HEUR thickener yog cov kua dej khov uas muaj diol lossis diol ether ua cov co-solvent, nrog cov khoom khov ntawm 20% ~ 40%. Lub luag haujlwm ntawm cov co-solvent yog los tiv thaiv kev nplaum, txwv tsis pub cov thickeners no nyob rau hauv lub xeev gel ntawm tib qhov concentration. Tib lub sijhawm, qhov muaj cov kuab tshuaj tuaj yeem tiv thaiv cov khoom kom tsis txhob khov, tab sis nws yuav tsum tau sov so thaum lub caij ntuj no ua ntej siv.

3. Cov khoom uas tsis khov thiab tsis muaj viscosity yooj yim pov tseg thiab tuaj yeem thauj thiab khaws cia rau hauv qhov ntau. Yog li ntawd, qee cov HEUR thickeners muaj cov khoom khov sib txawv ntawm cov khoom tib yam. Cov ntsiab lus co-solvent ntawm cov thickeners uas tsis muaj viscosity siab dua, thiab qhov nruab nrab-shear viscosity ntawm cov xim yuav qis dua me ntsis thaum siv, uas tuaj yeem raug txo los ntawm kev txo cov co-solvent ntxiv rau lwm qhov hauv cov mis.

4. Nyob rau hauv cov xwm txheej sib xyaw tsim nyog, HEUR uas muaj viscosity tsawg tuaj yeem ntxiv ncaj qha rau cov xim latex. Thaum siv cov khoom viscosity siab, cov thickener yuav tsum tau diluted nrog cov dej sib xyaw thiab co-solvent ua ntej nws tuaj yeem ntxiv. Yog tias koj ntxiv dej kom dilute cov thickener ncaj qha, nws yuav txo qhov concentration ntawm cov co-solvent thawj hauv cov khoom, uas yuav ua rau kom muaj kev sib txuas thiab ua rau viscosity nce.

5. Kev ntxiv cov tshuaj nplaum rau hauv lub tank sib tov yuav tsum ruaj khov thiab qeeb, thiab yuav tsum muab tso rau ntawm lub tank phab ntsa. Qhov ceev ntawm kev ntxiv yuav tsum tsis txhob ceev heev uas cov tshuaj nplaum nyob rau ntawm qhov chaw ntawm cov kua, tab sis yuav tsum rub mus rau hauv cov kua thiab tig mus rau hauv qhov sib tov, txwv tsis pub cov tshuaj nplaum yuav tsis sib tov zoo lossis cov tshuaj nplaum yuav tuab dhau lossis sib xyaw vim muaj qhov concentration hauv zos siab.

6. HEUR thickener raug ntxiv rau hauv lub tank sib tov xim tom qab lwm cov khoom ua kua thiab ua ntej emulsion, kom ntseeg tau tias qhov ci ntsa iab tshaj plaws.

7. HASE thickeners raug ntxiv ncaj qha rau cov xim hauv daim ntawv ntawm emulsion hauv kev tsim cov xim emulsion yam tsis muaj kev dilution ua ntej lossis pre-neutralization. Nws tuaj yeem ntxiv ua cov khoom kawg hauv theem sib tov, hauv theem pigment dispersion, lossis ua thawj cov khoom hauv kev sib tov.

8. Vim tias HASE yog cov emulsion uas muaj kua qaub ntau, tom qab ntxiv, yog tias muaj alkali hauv cov xim emulsion, nws yuav sib tw rau cov alkali no. Yog li ntawd, nws yuav tsum tau ntxiv cov HASE thickener emulsion maj mam thiab ruaj khov, thiab do kom zoo, txwv tsis pub, nws yuav ua rau lub kaw lus pigment dispersion lossis emulsion binder tsis ruaj khov hauv zos, thiab qhov kawg tau ruaj khov los ntawm pawg neutralized surface.

9. Alkali tuaj yeem ntxiv ua ntej lossis tom qab ntxiv cov neeg sawv cev thickening. Qhov zoo ntawm kev ntxiv ua ntej yog kom ntseeg tau tias tsis muaj kev tsis ruaj khov hauv zos ntawm cov xim dispersion lossis emulsion binder yuav tshwm sim los ntawm cov thickener grabs alkali ntawm qhov chaw ntawm cov xim lossis binder. Qhov zoo ntawm kev ntxiv cov alkali tom qab yog tias cov khoom thickener tau tawg zoo ua ntej lawv o lossis yaj los ntawm alkali, tiv thaiv kev thickening hauv zos lossis agglomeration, nyob ntawm cov qauv, cov khoom siv thiab cov txheej txheem tsim khoom. Txoj kev nyab xeeb tshaj plaws yog dilute HASE thickener nrog dej ua ntej thiab tom qab ntawd neutralize nws nrog alkali ua ntej.

10. HASE thickener pib o ntawm pH li ntawm 6, thiab qhov ua kom tuab tuaj yeem ua si tag nrho ntawm pH ntawm 7 txog 8. Kev kho qhov pH ntawm cov xim latex kom siab dua 8 tuaj yeem ua rau pH ntawm cov xim latex tsis txhob txo qis dua 8, yog li ua kom ntseeg tau tias qhov ruaj khov ntawm viscosity.