Hydroxypropyl methylcellulose (HPMC) yog ib hom polymer semi-synthetic, inert, tsis muaj tshuaj lom uas yaj tau hauv dej thiab siv dav hauv kev lag luam xws li tshuaj, khoom noj, tshuaj pleev ib ce thiab cov ntaub ntawv siv hauv tsev. Kev sib raug zoo ntawm nws qhov hnyav molecular thiab viscosity muaj feem cuam tshuam loj heev rau nws cov kev ua tau zoo hauv ntau yam kev siv.
1. Kev yaj thiab cov khoom tsim zaj duab xis
Qhov viscosity ntawm HPMC cuam tshuam ncaj qha rau nws qhov solubility hauv dej. HPMC nrog viscosity qis dua tuaj yeem yaj hauv dej sai dua thiab tsim cov tshuaj pob tshab thiab sib xws, uas yog qhov tsim nyog rau cov ntawv thov uas xav tau kev sib kis sai, xws li cov dej haus tam sim ntawd lossis cov tshuaj tam sim ntawd. HPMC nrog viscosity siab dua xav tau lub sijhawm yaj ntev dua, tab sis tuaj yeem muab qhov tuab thiab lub zog zoo dua thaum tsim cov zaj duab xis, yog li nws tsim nyog rau kev txheej ntsiav tshuaj, zaj duab xis tiv thaiv thiab ua cov khoom siv matrix hauv kev npaj tso tawm tas mus li.
2. Kev ruaj khov thiab kev nplaum
HPMC uas muaj viscosity siab dua feem ntau muaj kev ruaj khov thiab kev nplaum zoo dua. Piv txwv li, thaum siv los ua cov khoom siv tuab rau cov cement lossis gypsum hauv cov ntaub ntawv tsim kho, viscosity siab dua HPMC tuaj yeem txhim kho nws cov dej khaws cia thiab kev tiv thaiv sag, pab txuas ntxiv lub sijhawm tsim kho thiab txo qhov tawg. Hauv kev lag luam tshuaj, HPMC uas muaj viscosity siab yog siv los tswj tus nqi tso tawm tshuaj. Nws qhov kev nplaum siab tso cai rau cov tshuaj kom maj mam tso tawm hauv lub cev thiab txhim kho kev siv tshuaj ntawm cov tshuaj.
3. Kev ncua thiab emulsification
Kev hloov pauv ntawm viscosity kuj cuam tshuam rau qhov kev ncua thiab emulsification ntawm HPMC. Vim nws cov saw molecular luv luv, HPMC qis-viscosity yog qhov tsim nyog rau kev siv ua tus neeg sawv cev ncua. Nws tuaj yeem ua kom zoo ncua cov khoom tsis yaj hauv cov tshuaj kua thiab tiv thaiv kom tsis txhob muaj nag. HPMC nrog viscosity siab tuaj yeem tsim cov qauv network muaj zog hauv cov tshuaj vim nws cov saw molecular ntev dua, yog li nws ua tau zoo dua hauv kev ruaj khov ntawm emulsions thiab kev ncua thiab tuaj yeem tswj tau qhov sib xws ntev.
4. Rheology thiab daim ntawv thov khoom
Cov khoom rheological ntawm HPMC kuj yog ib qho tseem ceeb uas cuam tshuam los ntawm viscosity. Cov tshuaj HPMC qis-viscosity qhia tau tias muaj fluidity zoo dua, yooj yim rau txau thiab thov, thiab feem ntau siv rau hauv cov khoom tu tawv nqaij thiab xim. Cov tshuaj HPMC siab-viscosity ua haujlwm zoo li cov kua tsis-Newtonian thiab muaj cov yam ntxwv shear-thinning. Cov yam ntxwv no ua rau HPMC siab-viscosity yooj yim dua rau kev tuav hauv qab cov xwm txheej siab shear, thaum tswj hwm viscosity siab nyob rau hauv cov xwm txheej zoo li qub, yog li txhim kho cov zaj duab xis-tsim thiab kev ruaj khov ntawm cov khoom.
5. Piv txwv ntawm daim ntawv thov
Kev lag luam tshuaj: HPMC uas muaj viscosity tsawg (xws li 50 cps) feem ntau siv rau kev txheej cov ntsiav tshuaj uas tso tawm tam sim ntawd kom ntseeg tau tias cov tshuaj tso tawm sai, thaum HPMC uas muaj viscosity siab (xws li 4000 cps) siv rau cov ntsiav tshuaj uas tso tawm tas mus li kom kho qhov nrawm ntawm kev tso tawm tshuaj.
Zaub mov teb: Hauv cov dej haus tam sim ntawd, HPMC uas muaj viscosity qis tuaj yeem yaj sai yam tsis muaj clumping; hauv cov khoom ci, HPMC uas muaj viscosity siab tuaj yeem txhim kho lub peev xwm tuav dej ntawm cov khob cij thiab txhim kho cov saj thiab cov khoom noo noo ntawm cov khoom ci.
Kev tsim kho thaj chaw: Hauv cov putties thiab coatings, qis-viscosity HPMC pab txhawb kev tsim kho thiab txhim kho kev ua haujlwm zoo; thaum siab-viscosity HPMC txhim kho qhov tuab thiab sag tsis kam ntawm lub txheej.
Qhov viscosity ntawm HPMC yog qhov tseem ceeb uas txiav txim siab nws cov kev ua tau zoo hauv daim ntawv thov. HPMC viscosity qis feem ntau yog siv qhov twg xav tau kev yaj sai thiab kev ntws, thaum HPMC viscosity siab muaj txiaj ntsig zoo dua hauv cov ntawv thov uas xav tau kev nplaum siab, kev tsim zaj duab xis zoo thiab kev ruaj khov. Yog li ntawd, kev xaiv HPMC nrog qhov viscosity zoo yog qhov tseem ceeb rau kev ua kom zoo dua nws cov kev ua tau zoo hauv ntau qhov chaw.
Lub sijhawm tshaj tawm: Lub Xya Hli-08-2024