Cov khoom rheological ntawm HPMC yog dab tsi?

Dab tsi yog cov yam ntxwv rheological ntawm cov tshuaj?HPMC?

Hydroxypropyl methylcellulose (HPMC) yog ib qho polymer uas siv tau ntau yam hauv ntau yam lag luam, suav nrog tshuaj, kev tsim kho, khoom noj, thiab tshuaj pleev ib ce, feem ntau yog vim nws cov khoom rheological tshwj xeeb. Rheology yog kev kawm txog kev ntws thiab kev hloov pauv ntawm cov ntaub ntawv, thiab kev nkag siab txog cov khoom rheological ntawm HPMC yog qhov tseem ceeb rau kev ua kom zoo dua nws cov kev ua tau zoo hauv ntau daim ntawv thov.

Viscosity: HPMC qhia txog tus cwj pwm pseudoplastic lossis shear-thinning, txhais tau tias nws cov viscosity txo qis nrog kev nce ntxiv ntawm shear rate. Cov khoom no yog qhov tseem ceeb hauv cov ntawv thov xws li cov tshuaj tsim, qhov twg nws tso cai rau kev yooj yim pumping, kis, thiab daim ntawv thov. Viscosity tuaj yeem hloov kho los ntawm kev hloov kho qib ntawm kev hloov pauv (DS) thiab qhov hnyav molecular ntawm HPMC.

Thixotropy: Thixotropy yog hais txog kev hloov pauv gel-sol uas tau pom los ntawm qee cov ntaub ntawv hauv qab kev ntxhov siab shear. HPMC gels tsim thaum so tuaj yeem tawg hauv qab shear thiab rov qab tau lawv cov qauv gel thaum kev ntxhov siab raug tshem tawm. Cov cuab yeej no muaj txiaj ntsig zoo hauv kev siv xws li xim, qhov twg nws tiv thaiv kev sagging thaum thov tab sis ua kom muaj txheej txheem zoo thaum thov.

Kev Ua Kom Qhuav: HPMC yog hygroscopic thiab tuaj yeem nqus dej, ua rau o thiab nce viscosity. Qib ntawm kev ua kom qhuav nyob ntawm cov yam xws li kub, pH, thiab ionic zog ntawm cov khoom ib puag ncig. Kev ua kom qhuav ua lub luag haujlwm tseem ceeb hauv kev tswj kev tso tawm cov tshuaj los ntawm cov tshuaj thiab tswj cov dej noo hauv cov khoom noj.

Kev Kub Siab:HPMCCov tshuaj muaj viscosity nyob ntawm qhov kub thiab txias, nrog rau viscosity txo qis thaum qhov kub nce. Txawm li cas los xij, tus cwj pwm no tuaj yeem sib txawv nyob ntawm cov yam xws li polymer concentration thiab pH ntawm cov tshuaj. Kev rhiab heev ntawm qhov kub thiab txias yog qhov tseem ceeb hauv cov ntawv thov xws li cov ntaub ntawv tsim kho, qhov twg nws cuam tshuam rau kev ua haujlwm thiab lub sijhawm teeb tsa.

Kev Rhiab Ntshav: Cov tshuaj HPMC yuav ua rau muaj kev rhiab rau cov ntsev, nrog rau qee cov ntsev ua rau viscosity nce thiab lwm tus ua rau viscosity txo qis. Qhov xwm txheej no yog vim muaj kev sib cuam tshuam ntawm HPMC molecules thiab ions hauv cov tshuaj. Kev rhiab ntshav yog qhov tseem ceeb hauv cov tshuaj thiab cov khoom noj uas cov ntsev yuav tsum tau tswj hwm kom zoo.

Kev Nyob Ntawm Tus Nqi Shear: Cov khoom rheological ntawm HPMC cov kev daws teeb meem yog nyob ntawm tus nqi shear siv. Ntawm tus nqi shear qis, viscosity siab dua vim muaj kev sib txuas ntawm molecular, thaum ntawm tus nqi shear siab, viscosity txo qis vim yog shear thinning. Kev nkag siab txog kev nyob ntawm tus nqi shear yog qhov tseem ceeb rau kev tsim cov xwm txheej ua haujlwm hauv ntau yam kev siv.

Kev Nchuav Cov Khoom Me Me: HPMC tuaj yeem ua haujlwm ua tus neeg sawv cev rau cov khoom me me hauv cov kua vim nws cov khoom ua kom tuab thiab ruaj khov. Nws pab tiv thaiv kev sib sau ua ke ntawm cov khoom khov, ua kom muaj kev faib tawm thiab kev sib xws hauv cov khoom xws li xim, nplaum, thiab cov tshuaj ncua.

Kev Tsim Gel:HPMCtuaj yeem tsim cov gels ntawm cov concentration siab lossis nyob rau hauv qhov muaj cov neeg sawv cev crosslinking xws li divalent cations. Cov gels no qhia txog cov khoom viscoelastic thiab siv rau hauv cov ntawv thov xws li kev tswj hwm kev xa tshuaj, qhov twg xav tau kev tso tawm cov khoom xyaw nquag.

Cov khoom rheological ntawm HPMC, suav nrog viscosity, thixotropy, hydration, kub thiab ntsev rhiab heev, shear rate dependence, particle suspension, thiab gel tsim, ua lub luag haujlwm tseem ceeb hauv kev txiav txim siab nws cov kev ua tau zoo hauv ntau yam kev siv hauv kev lag luam. Kev nkag siab thiab kev tswj hwm cov khoom no yog qhov tseem ceeb rau kev ua kom zoo dua ntawm kev tsim thiab kev ua cov khoom raws li HPMC.