Hydroxyethyl Cellulose (HEC)yog ib qho dej-soluble nonionic cellulose ether, uas yog dav siv rau hauv coatings, cov ntaub ntawv tsim kho, tshuaj, cov tshuaj txhua hnub thiab lwm yam teb. Txawm li cas los xij, HEC muaj cov dej solubility siab thiab hydrophobicity tsis muaj zog, uas yuav ua rau muaj kev txwv kev ua haujlwm hauv qee qhov kev siv. Yog li ntawd, hydrophobically hloov kho hydroxyethyl cellulose (HMHEC) tau los ua kom nws cov khoom rheological, thickening muaj peev xwm, emulsification stability thiab dej tsis kam.
1. Qhov tseem ceeb ntawm kev hloov kho hydrophobic ntawm hydroxyethyl cellulose
Txhim kho cov khoom tuab thiab cov khoom rheological
Kev hloov kho hydrophobic tuaj yeem txhim kho qhov muaj peev xwm tuab ntawm HEC, tshwj xeeb tshaj yog thaum cov nqi shear qis. Nws qhia tau tias muaj viscosity siab dua, uas pab txhim kho thixotropy thiab pseudoplasticity ntawm lub kaw lus. Cov khoom no tseem ceeb heev rau cov teb ntawm cov tshuaj pleev xim, cov kua dej drilling hauv av, cov khoom siv tu tus kheej, thiab lwm yam, thiab tuaj yeem txhim kho qhov ruaj khov thiab siv cov nyhuv ntawm cov khoom.
Txhim kho qhov ruaj khov ntawm emulsion
Vim tias HEC uas tau hloov kho tuaj yeem tsim cov qauv sib koom ua ke hauv cov kua dej, nws ua rau lub emulsion ruaj khov dua, txo tau kev sib cais roj-dej, thiab txhim kho cov nyhuv emulsification. Yog li ntawd, nws muaj txiaj ntsig zoo rau kev siv hauv cov teb ntawm cov txheej txheem emulsion, cov khoom tu tawv nqaij thiab cov khoom noj emulsifiers.
Txhim kho kev tiv thaiv dej thiab cov khoom ua yeeb yaj kiab
HEC ib txwm muaj hydrophilic heev thiab yooj yim yaj hauv cov av noo siab lossis dej, uas cuam tshuam rau cov dej tsis kam ntawm cov khoom. Los ntawm kev hloov kho hydrophobic, nws daim ntawv thov hauv coatings, adhesives, papermaking thiab lwm yam teb tuaj yeem txhim kho, thiab nws cov dej tsis kam thiab cov khoom ua yeeb yaj kiab tuaj yeem txhim kho.
Txhim kho cov khoom siv shear thinning
Hydrophobic-modified HEC tuaj yeem txo qhov viscosity nyob rau hauv cov xwm txheej siab shear, thaum tswj hwm qhov sib xws siab ntawm cov nqi qis shear, yog li txhim kho kev ua haujlwm ntawm kev tsim kho thiab txo kev siv hluav taws xob. Nws muaj txiaj ntsig tseem ceeb hauv kev lag luam xws li kev khawb av roj thiab kev tsim kho vaj tse.
2. Kev hloov kho hydrophobic ntawm hydroxyethyl cellulose
Kev hloov kho hydrophobic HEC feem ntau yog ua tiav los ntawm kev qhia cov pab pawg hydrophobic los kho nws cov solubility thiab cov khoom tuab los ntawm kev siv tshuaj grafting lossis kev hloov kho lub cev. Cov txheej txheem hloov kho hydrophobic feem ntau yog raws li nram no:
Kev sib txuas ua pawg hydrophobic
Qhia cov alkyl (xws li hexadecyl), aryl (xws li phenyl), siloxane lossis fluorinated pawg ntawm HEC molecule los ntawm kev tshuaj lom neeg los txhim kho nws cov hydrophobicity. Piv txwv li:
Siv cov tshuaj esterification lossis etherification reaction los graft long-saw alkyl, xws li hexadecyl lossis octyl, los tsim cov qauv hydrophobic associating.
Qhia cov pab pawg silicone los ntawm kev hloov kho siloxane los txhim kho nws cov dej tsis kam thiab lubricity.
Siv kev hloov kho fluorination los txhim kho kev tiv thaiv huab cua thiab hydrophobicity, ua rau nws tsim nyog rau cov txheej txheem siab lossis cov ntawv thov ib puag ncig tshwj xeeb.
Kev sib txuas ua ke lossis kev hloov pauv hla kev sib txuas
Los ntawm kev qhia cov comonomers (xws li acrylates) lossis cov neeg sawv cev sib txuas (xws li epoxy resins) los tsim ib lub network sib txuas, qhov tsis kam dej thiab lub peev xwm tuab ntawm HEC tau zoo dua. Piv txwv li, siv hydrophobically hloov HEC hauv polymer emulsions tuaj yeem txhim kho qhov ruaj khov thiab thickening effect ntawm emulsion.
Kev hloov kho lub cev
Siv cov txheej txheem adsorption lossis txheej txheem txheej txheem, cov hydrophobic molecules raug coated rau ntawm qhov chaw ntawm HEC los tsim ib qho hydrophobicity. Txoj kev no yog qhov tsis hnyav thiab haum rau cov ntawv thov nrog cov kev xav tau siab rau kev ruaj khov tshuaj lom neeg, xws li zaub mov thiab tshuaj.
Kev hloov kho ntawm kev sib koom ua ke hydrophobic
Los ntawm kev qhia me me ntawm cov pab pawg hydrophobic rau ntawm HEC molecule, nws tsim cov khoom sib xyaw ua ke hauv cov kua dej, yog li txhim kho lub peev xwm ua kom tuab. Txoj kev no siv dav hauv kev tsim cov khoom ua kom tuab thiab tsim nyog rau cov txheej txheem, cov tshuaj roj av thiab lwm yam teb.
Kev hloov kho hydrophobic ntawmhydroxyethyl celluloseyog ib txoj hauv kev tseem ceeb 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 properties. Cov txheej txheem hloov kho feem ntau suav nrog hydrophobic group grafting, copolymerization lossis cross-linking modification, physical modification thiab hydrophobic association modification. Kev xaiv cov txheej txheem hloov kho tsim nyog tuaj yeem ua kom zoo dua qhov kev ua tau zoo ntawm HEC raws li cov kev xav tau ntawm daim ntawv thov sib txawv, yog li ua lub luag haujlwm tseem ceeb hauv ntau qhov chaw xws li architectural coatings, oilfield tshuaj, kev saib xyuas tus kheej, thiab tshuaj.
Lub sijhawm tshaj tawm: Lub Peb Hlis-25-2025