Hydroxypropyl Methylcellulose (HPMC) yog ib qho cellulose derivative uas siv ntau yam, xws li tshuaj, khoom noj, cov ntaub ntawv tsim kho thiab cov tshuaj pleev ib ce. HPMC yog ib qho non-ionic, semi-synthetic, inert polymer nrog cov dej zoo heev, thickening, adhesiveness thiab zaj duab xis-ua cov khoom.
Cov qauv thiab cov khoom ntawm HPMC
HPMC yog ib qho cellulose hloov kho uas tsim los ntawm kev sib xyaw cellulose nrog methyl chloride thiab propylene oxide. Nws cov qauv molecular muaj ob qho tib si methyl thiab hydroxypropyl substituents, uas muab HPMC cov khoom tshwj xeeb lub cev thiab tshuaj, xws li solubility zoo heev, kev tiv thaiv colloid thiab cov khoom tsim zaj duab xis. HPMC tuaj yeem muab faib ua ntau yam kev qhia raws li cov substituents sib txawv, thiab txhua qhov kev qhia muaj kev solubility sib txawv thiab siv hauv dej.
Kev yaj ntawm HPMC hauv dej
Txoj kev yaj
HPMC cuam tshuam nrog cov dej molecules los ntawm hydrogen bonds los tsim cov tshuaj. Nws cov txheej txheem yaj suav nrog cov dej molecules maj mam nkag mus rau ntawm cov saw hlau molecular ntawm HPMC, rhuav tshem nws cov cohesion, yog li cov saw hlau polymer diffuse rau hauv dej los tsim cov tshuaj sib xws. Qhov solubility ntawm HPMC muaj feem cuam tshuam nrog nws qhov hnyav molecular, hom substituent thiab qib ntawm kev hloov pauv (DS). Feem ntau, qhov siab dua ntawm qib ntawm kev hloov pauv ntawm substituent, qhov siab dua ntawm solubility ntawm HPMC hauv dej.
Qhov cuam tshuam ntawm qhov kub thiab txias rau kev yaj
Kub yog ib qho ntawm cov yam tseem ceeb uas cuam tshuam rau qhov solubility ntawm HPMC. Qhov solubility ntawm HPMC hauv dej qhia txog cov yam ntxwv sib txawv thaum qhov kub hloov pauv:
Qhov kub ntawm kev yaj: HPMC nyuaj rau yaj hauv dej txias (feem ntau qis dua 40 ° C), tab sis nws tuaj yeem yaj sai dua thaum cua sov rau 60 ° C lossis siab dua. Rau HPMC uas muaj viscosity tsawg, qhov kub ntawm dej li ntawm 60 ° C feem ntau yog qhov kub zoo tshaj plaws rau kev yaj. Rau HPMC uas muaj viscosity siab, qhov kub zoo tshaj plaws rau kev yaj yuav siab txog 80 ° C.
Gelation thaum lub sijhawm txias: Thaum cov tshuaj HPMC raug cua sov rau qee qhov kub (feem ntau 60-80 ° C) thaum lub sijhawm yaj thiab tom qab ntawd maj mam txias, cov tshuaj thermal gel yuav tsim. Cov tshuaj thermal gel no ruaj khov tom qab txias mus rau qhov kub thiab txias thiab tuaj yeem rov ua dua hauv dej txias. Qhov xwm txheej no yog qhov tseem ceeb heev rau kev npaj cov tshuaj HPMC rau qee lub hom phiaj tshwj xeeb (xws li cov tshuaj capsules tso tawm).
Kev ua haujlwm ntawm kev yaj: Feem ntau, qhov kub siab dua tuaj yeem ua rau cov txheej txheem yaj ntawm HPMC sai dua. Txawm li cas los xij, qhov kub siab dhau kuj tseem tuaj yeem ua rau polymer puas tsuaj lossis txo qis qhov viscosity ntawm kev yaj. Yog li ntawd, thaum ua haujlwm tiag tiag, qhov kub yaj tsim nyog yuav tsum tau xaiv raws li qhov xav tau kom tsis txhob muaj kev puas tsuaj tsis tsim nyog thiab kev hloov pauv ntawm cov khoom.
Cov nyhuv ntawm pH rau kev yaj
Ua ib qho polymer uas tsis yog ionic, qhov solubility ntawm HPMC hauv dej tsis cuam tshuam ncaj qha los ntawm tus nqi pH ntawm cov tshuaj. Txawm li cas los xij, cov xwm txheej pH hnyav (xws li cov chaw muaj zog acidic lossis alkaline) yuav cuam tshuam rau cov yam ntxwv ntawm kev yaj ntawm HPMC:
Cov xwm txheej acidic: Nyob rau hauv cov xwm txheej acidic muaj zog (pH <3), qee cov tshuaj sib txuas ntawm HPMC (xws li ether bonds) yuav raug rhuav tshem los ntawm cov kua qaub nruab nrab, yog li cuam tshuam rau nws cov solubility thiab dispersibility. Txawm li cas los xij, nyob rau hauv cov kua qaub tsis muaj zog dav dav (pH 3-6), HPMC tseem tuaj yeem yaj zoo. Cov xwm txheej alkaline: Nyob rau hauv cov xwm txheej alkaline muaj zog (pH > 11), HPMC yuav degrade, uas feem ntau yog vim cov tshuaj hydrolysis ntawm cov saw hydroxypropyl. Nyob rau hauv cov xwm txheej alkaline tsis muaj zog (pH 7-9), solubility ntawm HPMC feem ntau tsis cuam tshuam loj heev.
Txoj kev yaj ntawm HPMC
Yuav kom yaj tau HPMC zoo, cov hau kev hauv qab no feem ntau yog siv:
Txoj kev faib dej txias: Maj mam ntxiv hmoov HPMC rau hauv dej txias thaum do kom sib npaug. Txoj kev no tuaj yeem tiv thaiv HPMC kom tsis txhob sib sau ua ke hauv dej, thiab cov tshuaj tsim ib txheej tiv thaiv colloidal. Tom qab ntawd, maj mam ua kom sov rau 60-80 ° C kom yaj tag. Txoj kev no haum rau kev yaj feem ntau ntawm HPMC.
Txoj kev faib dej kub: Ntxiv HPMC rau hauv dej kub thiab do nws sai sai kom yaj nws sai sai ntawm qhov kub siab. Txoj kev no yog qhov tsim nyog rau HPMC uas muaj viscosity siab, tab sis yuav tsum tau them sai sai rau kev tswj qhov kub kom tsis txhob muaj kev puas tsuaj.
Txoj kev npaj ua ntej rau kev daws teeb meem: Ua ntej, HPMC raug yaj rau hauv cov organic solvent (xws li ethanol), thiab tom qab ntawd maj mam ntxiv dej kom hloov nws mus ua cov kua dej. Txoj kev no haum rau cov xwm txheej thov tshwj xeeb nrog cov kev xav tau solubility siab.
Kev siv txoj kev daws teeb meem hauv kev siv tiag tiag
Hauv kev siv ua haujlwm, cov txheej txheem yaj ntawm HPMC yuav tsum tau ua kom zoo raws li kev siv tshwj xeeb. Piv txwv li, hauv kev lag luam tshuaj, feem ntau nws yog qhov tsim nyog los tsim cov tshuaj colloidal uas sib xws thiab ruaj khov, thiab kev tswj hwm qhov kub thiab pH nruj nreem yog qhov yuav tsum tau ua kom ntseeg tau tias qhov viscosity thiab kev ua haujlwm ntawm cov tshuaj. Hauv cov ntaub ntawv tsim kho, qhov solubility ntawm HPMC cuam tshuam rau cov khoom tsim zaj duab xis thiab lub zog compressive, yog li txoj kev yaj zoo tshaj plaws yuav tsum tau xaiv ua ke nrog cov xwm txheej ib puag ncig tshwj xeeb.
Qhov solubility ntawm HPMC hauv dej yog cuam tshuam los ntawm ntau yam, tshwj xeeb tshaj yog kub thiab pH. Feem ntau hais lus, HPMC yaj sai dua ntawm qhov kub siab dua (60-80 ° C), tab sis tej zaum yuav degrade lossis ua tsawg dua soluble nyob rau hauv cov xwm txheej pH hnyav. Yog li ntawd, hauv kev siv ua haujlwm, nws yog qhov tsim nyog los xaiv qhov kub yaj thiab pH ntau raws li kev siv tshwj xeeb thiab cov xwm txheej ib puag ncig ntawm HPMC kom ntseeg tau tias nws cov solubility zoo thiab kev ua tau zoo.
Lub sijhawm tshaj tawm: Lub Rau Hli-25-2024