Hydroxyethyl cellulose (HEC) yog dej-soluble non-ionic cellulose ether. Nws yog dav siv nyob rau hauv dej-raws li coatings vim hais tias ntawm nws zoo thickening, emulsifying, film-forming thiab suspending zog. Raws li cov thickener thiab stabilizer nyob rau hauv cov txheej txheem, HEC tuaj yeem txhim kho cov khoom rheological thiab pleev xim ntawm cov txheej.
1. Lub luag haujlwm tseem ceeb ntawm hydroxyethyl cellulose
Hauv cov txheej txheem dej, lub luag haujlwm tseem ceeb ntawm HEC tau pom hauv cov hauv qab no:
Thickening nyhuv: HEC muaj zog thickening muaj peev xwm, uas tuaj yeem txhim kho cov viscosity thiab ncua kev muaj peev xwm ntawm cov dej-raws li txheej thiab tiv thaiv cov pigments thiab fillers nyob rau hauv lub txheej los ntawm kev daws.
Txhim kho rheology: HEC tuaj yeem kho cov kua dej hauv cov txheej txheem dej kom nws nthuav tawm cov viscosity tsawg nyob rau hauv siab shear, ua kom yooj yim rau kev sib kis thaum pleev xim, thaum nthuav tawm cov viscosity siab dua nyob rau hauv cov xwm txheej zoo li qub, yog li txo qhov ntws ntawm cov xim. dai phenomenon.
Txhim khu kev ruaj ntseg: HEC muaj qhov zoo khov-thaw tsis kam thiab cia ruaj khov, uas tuaj yeem txuas ntxiv lub neej txee ntawm cov txheej thiab ua kom muaj kev ruaj ntseg hauv ntau qhov chaw.
Txhim kho zaj duab xis-tsim cov khoom: HEC tsim cov yeeb yaj kiab hloov pauv tom qab cov xim dries, txhim kho cov adhesion thiab hnav tsis kam ntawm cov xim zaj duab xis thiab txhim kho kev tiv thaiv kev ua haujlwm ntawm cov xim.
2. Yuav siv HEC li cas
Thaum siv HEC nyob rau hauv cov dej-raws li txheej, dispersion thiab dissolution txoj kev thiab ncaj qha ntxiv txoj kev feem ntau yog siv. Cov hauv qab no yog cov kauj ruam thiab kev siv tshwj xeeb:
() 1. Pretreatment kom yaj HEC
HEC yog cov hmoov uas tsis yooj yim rau yaj ncaj qha thiab yooj yim tsim clumps hauv dej. Yog li ntawd, ua ntej ntxiv HEC, nws raug pom zoo kom ua ntej disperse nws. Cov kauj ruam ib txwm muaj raws li hauv qab no:
Do thiab disperse: Maj mam ntxiv HEC rau cov dej hauv qab qis qis kom tsis txhob tsim cov clumps. Tus nqi ntawm HEC ntxiv yuav tsum tau hloov kho raws li qhov xav tau ntawm viscosity ntawm txheej, feem ntau suav nrog 0.3% -1% ntawm tag nrho cov qauv.
Tiv thaiv caking: Thaum ntxiv HEC, ib qho me me ntawm cov tshuaj tiv thaiv caking, xws li ethanol, propylene glycol, thiab lwm yam, tuaj yeem muab ntxiv rau hauv dej kom cov HEC hmoov sib npaug sib npaug thiab txo qhov muaj peev xwm ntawm caking.
(2). Txoj kev dispersion thiab dissolution
Txoj kev dispersion thiab dissolution yog kom yaj HEC cais rau hauv cov kua nplaum thaum lub sij hawm npaj cov xim, thiab ces ntxiv rau cov xim. Cov kauj ruam tshwj xeeb yog raws li hauv qab no:
Cov txheej txheem tawg: HEC yog qhov nyuaj rau yaj ntawm qhov kub thiab txias, yog li dej tuaj yeem ua kom sov kom tsim nyog kom ncav cuag qhov kub ntawm 30-40 ° C kom nrawm nrawm ntawm HEC.
Lub sij hawm stirring: HEC dissolves maj mam thiab feem ntau yuav tsum tau nplawm rau 0.5-2 teev kom txog thaum nws tag nrho yaj mus rau hauv cov pob tshab los yog translucent viscous kua.
Kho tus nqi pH: Tom qab HEC yaj, pH tus nqi ntawm cov tshuaj tuaj yeem hloov kho raws li qhov xav tau, feem ntau yog nyob nruab nrab ntawm 7-9, txhawm rau txhim kho kev ruaj ntseg ntawm txheej.
(3). Direct ntxiv txoj kev
Txoj kev sib txuas ncaj qha yog ntxiv HEC ncaj qha rau hauv txheej txheej txheej txheej txheej txheej txheej txheej txheej txheej txheej txheej, uas yog tsim rau txheej txheej txheej txheem tshwj xeeb. Thov ua tib zoo mloog cov ntsiab lus hauv qab no thaum ua haujlwm:
Qhuav ua ntej thiab ces ntub: NtxivHECmus rau qhov qhuav ntawm cov xim pleev xim dej ua ntej, sib tov nws tusyees nrog lwm cov hmoov, thiab tom qab ntawd ntxiv dej thiab cov khoom ua kua kom tsis txhob agglomeration.
Shear tswj: Thaum ntxiv HEC rau cov txheej, nws yog ib qho tsim nyog yuav tsum siv cov cuab yeej sib xyaw ua ke, xws li lub tshuab hluav taws xob nrawm, kom HEC tuaj yeem sib cais sib npaug hauv lub sijhawm luv luv thiab ncav cuag qhov xav tau viscosity.
3. Kev tswj hwm ntawm HEC ntau npaum
Hauv cov txheej txheem dej, tus nqi ntawm HEC yuav tsum tau tswj raws li qhov xav tau tiag tiag ntawm txheej txheej. HEC ntau dhau yuav ua rau cov txheej txheej viscosity siab dhau thiab cuam tshuam rau kev ua haujlwm; HEC tsawg dhau yuav tsis ua tiav qhov kev cia siab thickening nyhuv. Raws li ib txwm muaj, qhov ntau npaum li cas ntawm HEC yog tswj hwm ntawm 0.3% -1% ntawm tag nrho cov qauv, thiab cov kev faib ua feem tuaj yeem hloov kho los ntawm kev sim.
4. Kev ceev faj rau HEC hauv cov txheej txheem dej
Tsis txhob agglomeration: HEC nyhav rau agglomerate hauv dej, yog li thaum ntxiv nws, ntxiv nws maj mam li sai tau, disperse nws tusyees, thiab tsis txhob sib tov ntawm huab cua kom ntau li ntau tau.
Dissolution kub: HEC yaj sai dua ntawm qhov kub thiab txias, tab sis qhov kub yuav tsum tsis txhob siab tshaj 50 ° C, txwv tsis pub nws cov viscosity yuav cuam tshuam.
stirring tej yam kev mob: Nruam nplawm yog yuav tsum tau thaum lub sij hawm dissolution txheej txheem ntawm HEC, thiab ntim nrog hau yuav tsum tau siv ntau li ntau tau kom tsis txhob muaj kab mob los ntawm lwm yam impurities thiab evaporation ntawm dej.
Kev hloov kho ntawm tus nqi pH: Lub viscosity ntawm HEC yuav nce nyob rau hauv alkaline tej yam kev mob, yog li pH tus nqi ntawm cov tshuaj yuav tsum tau hloov kho kom tsim nyog los tiv thaiv cov kev ua tau zoo ntawm txheej los ntawm poob vim pH ntau dhau.
Kev ntsuam xyuas kev sib raug zoo: Thaum tsim cov qauv tshiab, kev siv HEC yuav tsum tau sim rau kev sib raug zoo nrog lwm cov thickeners, emulsifiers, thiab lwm yam kom ntseeg tau tias tsis muaj kev phiv tshwm sim.
5. Daim ntawv thov piv txwv ntawm HEC hauv cov txheej txheem dej
HEC tuaj yeem siv ua cov thickener nyob rau hauv ob qho tib si dej-raws li sab hauv phab ntsa coatings thiab dej-raws li sab nrauv phab ntsa txheej. Piv txwv li:
Dej-raws li phab ntsa pleev xim rau sab hauv: HEC yog siv los txhim kho cov qib theem ntawm cov xim, ua rau daim ntawv thov smoother thiab ntau dua, thiab txo cov txhuam hniav.
Dej-raws li sab nrauv phab ntsa txheej: HEC tuaj yeem txhim kho lub sag kuj thiab huab cua tsis kam ntawm cov txheej thiab zam kev puas tsuaj rau cov txheej txheej zaj duab xis los ntawm nag yaig.
Daim ntawv thov ntawm HEC hauv cov txheej txheem dej tsis tuaj yeem txhim kho kev tsim kho ntawm cov txheej txheem, tab sis kuj tseem txhim kho qhov pom tseeb thiab ua haujlwm ntev ntawm cov yeeb yaj kiab txheej. Hauv cov ntawv thov, raws li cov kev cai tshwj xeeb ntawm cov txheej txheem, cov txheej txheem kev sib cais thiab cov nyiaj ntxiv ntawm HEC yog tsim nyog, thiab ua ke nrog kev npaj ntawm lwm cov khoom siv raw, cov txheej txheem zoo tuaj yeem ua tiav.
Post lub sij hawm: Nov-10-2024