Hydroxyethyl Cellulose (HEC)yog ib qho dej-soluble nonionic cellulose ether, uas yog dav siv nyob rau hauv txheej, tsev cov ntaub ntawv, tshuaj, tshuaj txhua hnub thiab lwm yam teb. Txawm li cas los xij, HEC muaj cov dej solubility siab thiab tsis muaj zog hydrophobicity, uas yuav ua rau muaj kev txwv kev ua haujlwm hauv qee qhov kev thov. Yog li, hydrophobically hloov kho hydroxyethyl cellulose (HMHEC) tau los ua kom nws cov khoom rheological, thickening peev xwm, emulsification stability thiab dej tsis kam.
1. Qhov tseem ceeb ntawm kev hloov kho hydrophobic ntawm hydroxyethyl cellulose
Txhim kho thickening zog thiab rheological zog
Kev hloov kho hydrophobic tuaj yeem txhim kho lub peev xwm thickening ntawm HEC, tshwj xeeb tshaj yog nyob rau qis qis. Nws qhia tau hais tias muaj viscosity ntau dua, uas pab txhim kho thixotropy thiab pseudoplasticity ntawm lub cev. Cov cuab yeej no yog qhov tseem ceeb tshwj xeeb hauv cov txheej txheem txheej txheej, cov roj av drilling kua, cov khoom tu tus kheej, thiab lwm yam, thiab tuaj yeem txhim kho kev ruaj ntseg thiab siv cov khoom siv.
Txhim kho emulsion stability
Txij li HEC hloov kho tuaj yeem tsim cov qauv sib koom ua ke hauv cov tshuaj aqueous, nws txhim kho qhov ruaj khov ntawm emulsion, tuaj yeem txo cov roj-dej sib cais, thiab txhim kho cov nyhuv emulsification. Yog li ntawd, nws muaj txiaj ntsig zoo hauv daim teb ntawm emulsion txheej, cov khoom tu tawv nqaij thiab cov khoom noj emulsifiers.
Txhim kho cov dej tsis kam thiab ua cov yeeb yaj kiab
Ib txwm HEC yog hydrophilic heev thiab yooj yim soluble nyob rau hauv high humidity ib puag ncig los yog dej, uas cuam tshuam cov dej tsis kam ntawm cov khoom. Los ntawm kev hloov kho hydrophobic, nws daim ntawv thov hauv txheej, nplaum, papermaking thiab lwm yam kev lag luam tuaj yeem txhim kho, thiab nws cov dej tsis kam thiab cov yeeb yaj kiab tsim tuaj yeem txhim kho.
Txhim kho shear thinning zog
Hydrophobic-hloov HEC tuaj yeem txo cov viscosity nyob rau hauv siab shear tej yam kev mob, thaum tuav ib tug siab sib xws ntawm tsawg shear tus nqi, yog li txhim kho kev tsim kho kev ua tau zoo thiab txo lub zog noj. Nws muaj nuj nqis tseem ceeb hauv kev lag luam xws li oilfield mining thiab architectural coatings.
2. Kev hloov kho hydrophobic ntawm hydroxyethyl cellulose
HEC hydrophobic hloov kho feem ntau yog ua tiav los ntawm kev qhia cov pab pawg hydrophobic los kho nws cov solubility thiab thickening zog los ntawm tshuaj grafting los yog hloov lub cev. Cov kev hloov kho hydrophobic feem ntau yog raws li hauv qab no:
Hydrophobic pawg grafting
Qhia txog alkyl (xws li hexadecyl), aryl (xws li phenyl), siloxane lossis fluorinated pawg ntawm HEC molecule los ntawm cov tshuaj tiv thaiv los txhim kho nws cov hydrophobicity. Piv txwv li:
Siv esterification los yog etherification cov tshuaj tiv thaiv rau graft ntev-chain alkyl, xws li hexadecyl los yog octyl, los tsim ib tug hydrophobic associating qauv.
Qhia cov pab pawg silicone los ntawm kev hloov kho siloxane los txhim kho nws cov dej tsis kam thiab lubricity.
Siv fluorination hloov kho los txhim kho huab cua tsis kam thiab hydrophobicity, ua rau nws haum rau high-end coatings los yog tshwj xeeb ib puag ncig daim ntaub ntawv.
Copolymerization los yog kev hloov pauv kev sib txuas
Los ntawm kev qhia cov comonomers (xws li acrylates) los yog cov kab sib txuas sib txuas (xws li epoxy resins) los tsim cov kev sib txuas sib txuas, cov dej tsis kam thiab cov peev xwm thickening ntawm HEC tau txhim kho. Piv txwv li, siv hydrophobically hloov HEC hauv polymer emulsions tuaj yeem txhim kho qhov ruaj khov thiab thickening nyhuv ntawm emulsion.
Kev hloov kho lub cev
Siv deg adsorption lossis txheej thev naus laus zis, hydrophobic molecules yog coated rau ntawm HEC los tsim ib qho hydrophobicity. Txoj kev no yog qhov me me thiab tsim nyog rau cov ntawv thov uas xav tau kev ruaj ntseg tshuaj lom neeg, xws li zaub mov thiab tshuaj.
Kev hloov pauv ntawm Hydrophobic Association
Los ntawm kev qhia me me ntawm cov pab pawg hydrophobic ntawm HEC molecule, nws tsim ib qho kev sib sau ua ke hauv cov kua dej aqueous, yog li txhim kho lub peev xwm thickening. Txoj kev no yog siv dav hauv kev tsim cov thickeners ua haujlwm siab thiab tsim nyog rau txheej txheej, roj av tshuaj thiab lwm yam.
Hydrophobic kev hloov kho ntawmhydroxyethyl celluloseyog ib qho tseem ceeb txhais tau tias los txhim kho nws daim ntawv thov kev ua tau zoo, uas tuaj yeem txhim kho nws lub peev xwm thickening, emulsification stability, dej tsis kam thiab rheological zog. Cov kev hloov kho feem ntau muaj xws li hydrophobic group grafting, copolymerization los yog cross-linking modification, kev hloov kho lub cev thiab kev hloov kho hydrophobic Association. Kev xaiv tsim nyog ntawm kev hloov kho tuaj yeem ua kom zoo dua qhov kev ua tau zoo ntawm HEC raws li kev thov sib txawv, yog li ua lub luag haujlwm ntau dua hauv ntau qhov chaw xws li cov txheej txheem vaj tsev, cov tshuaj siv roj av, kev saib xyuas tus kheej, thiab tshuaj.
Lub sij hawm xa tuaj: Mar-25-2025