Hydroxypropylmethylcellulose (HPMC) yog ib hom cellulose derivative uas feem ntau siv rau hauv ntau yam lag luam, suav nrog tshuaj, kev tsim kho thiab khoom noj. Nws qhov viscosity tuaj yeem sib txawv nyob ntawm cov yam xws li nws qhov hnyav molecular, qib kev hloov pauv, thiab qhov concentration ntawm cov kua.
Kev Taw Qhia Txog Hydroxypropyl Methylcellulose (HPMC)
Hydroxypropyl methylcellulose yog ib qho polymer semi-synthetic tau los ntawm kev hloov kho tshuaj ntawm cellulose. Vim nws cov yam ntxwv tshwj xeeb, nws yog siv dav ua tus thickener, gelling agent, film former thiab stabilizer hauv ntau yam kev siv.
Cov qauv molecular thiab cov qauv sib xyaw
HPMC muaj cov cellulose backbone nrog hydroxypropyl thiab methoxy substituents. Qib ntawm kev hloov pauv (DS) hais txog tus lej nruab nrab ntawm cov substituents ib chav anhydroglucose hauv cov saw cellulose. Tus nqi DS tshwj xeeb cuam tshuam rau cov khoom siv lub cev thiab tshuaj ntawm HPMC.
HPMC viscosity
Viscosity yog ib qho tseem ceeb rau HPMC, tshwj xeeb tshaj yog nyob rau hauv cov ntawv thov uas siv nws cov khoom thickening thiab gelling.
Qhov viscosity ntawm HPMC cov kev daws teeb meem yog cuam tshuam los ntawm ntau yam:
1. Qhov hnyav ntawm cov molecule
Qhov hnyav molecular ntawm HPMC cuam tshuam rau nws cov viscosity. Feem ntau, qhov hnyav molecular siab dua HPMCs feem ntau tsim cov kev daws teeb meem viscosity siab dua. Muaj ntau qib sib txawv ntawm HPMC ntawm kev ua lag luam, txhua tus muaj nws tus kheej qhov hnyav molecular.
2. Qib ntawm kev hloov pauv (DS)
Cov nqi DS ntawm hydroxypropyl thiab methoxy pawg cuam tshuam rau qhov solubility thiab viscosity ntawm HPMC. Cov nqi DS siab dua feem ntau ua rau muaj kev nce ntxiv ntawm cov dej solubility thiab cov tshuaj tuab dua.
3. Kev Ntsuas
Qhov concentration ntawm HPMC hauv cov kua yog qhov tseem ceeb uas cuam tshuam rau viscosity. Thaum concentration nce, viscosity feem ntau nce. Qhov kev sib raug zoo no feem ntau piav qhia los ntawm Krieger-Dougherty equation.
4. Kub
Kub kuj tseem cuam tshuam rau qhov viscosity ntawm HPMC cov kev daws teeb meem. Feem ntau hais lus, viscosity txo qis thaum kub nce.
Cov cheeb tsam thov
Cov Tshuaj: HPMC feem ntau siv rau hauv cov tshuaj tsim, suav nrog cov ntsiav tshuaj thiab cov tshuaj ophthalmic, qhov twg tswj kev tso tawm thiab viscosity yog qhov tseem ceeb.
Kev Tsim Kho: Hauv kev lag luam kev tsim kho, HPMC yog siv los ua cov khoom siv tuab hauv cov khoom siv cement los txhim kho kev ua haujlwm thiab kev khaws cia dej.
Kev Lag Luam Khoom Noj: HPMC yog siv los ua cov khoom ua kom tuab, stabilizer thiab emulsifier hauv cov ntawv thov zaub mov.
Qhov viscosity ntawm hydroxypropyl methylcellulose yog ib qho khoom nyuaj uas cuam tshuam los ntawm ntau yam xws li qhov hnyav molecular, qib ntawm kev hloov pauv, kev sib xyaw thiab kub. Muaj ntau qib sib txawv ntawm HPMC kom haum rau cov ntawv thov tshwj xeeb, thiab cov chaw tsim khoom muab cov ntaub ntawv qhia txog qhov ntau ntawm viscosity ntawm txhua qib hauv ntau yam xwm txheej. Cov kws tshawb fawb thiab cov neeg tsim qauv yuav tsum xav txog cov yam no los kho cov khoom ntawm HPMC kom ua tau raws li qhov xav tau ntawm lawv cov ntawv thov.
Lub sijhawm tshaj tawm: Lub Ib Hlis-20-2024