Hydroxypropyl methylcellulose (HPMC) yog ib qho kev siv dej-soluble polymer, dav siv hauv kev lag luam tshuaj, tshuaj pleev ib ce, zaub mov thiab kev lag luam, tshwj xeeb hauv kev npaj cov gels. Nws cov khoom siv lub cev thiab kev sib cais tus cwj pwm muaj feem cuam tshuam rau kev ua tau zoo hauv kev siv sib txawv. Lub gelation kub ntawm HPMC gel yog ib qho ntawm nws lub cev tseem ceeb, uas cuam tshuam ncaj qha rau nws cov kev ua tau zoo hauv ntau yam kev npaj, xws li kev tso tawm, kev tsim cov yeeb yaj kiab, kev ruaj ntseg, thiab lwm yam.
1. Cov qauv thiab cov khoom ntawm HPMC
HPMC yog ib qho dej-soluble polymer uas tau los ntawm kev qhia ob qho kev hloov pauv, hydroxypropyl thiab methyl, rau hauv cellulose molecular skeleton. Nws cov qauv molecular muaj ob hom kev hloov pauv: hydroxypropyl (-CH2CHOHCH3) thiab methyl (-CH3). Cov yam ntxwv xws li cov ntsiab lus sib txawv hydroxypropyl, qib ntawm methylation, thiab qib ntawm polymerization yuav muaj kev cuam tshuam tseem ceeb rau kev solubility, gelling tus cwj pwm, thiab cov khoom siv ntawm HPMC.
Hauv cov kev daws teeb meem aqueous, AnxinCel®HPMC tsim cov kev daws teeb meem ruaj khov colloidal los ntawm kev tsim cov hydrogen bonds nrog dej molecules thiab cuam tshuam nrog nws cov pob txha cellulose. Thaum qhov chaw sab nraud (xws li kub, ionic zog, thiab lwm yam) hloov, kev sib cuam tshuam ntawm HPMC molecules yuav hloov, ua rau gelation.
2. Cov ntsiab lus thiab cuam tshuam ntawm gelation kub
Gelation kub (Gelation Temperature, T_gel) yog hais txog qhov kub thiab txias ntawm cov tshuaj HPMC pib hloov los ntawm cov kua rau cov khoom thaum cov tshuaj kub nce mus rau ib theem. Ntawm qhov ntsuas kub no, kev txav ntawm HPMC cov saw hlau molecular yuav raug txwv, tsim cov qauv peb sab, ua rau muaj cov khoom zoo li gel.
Lub gelation kub ntawm HPMC cuam tshuam los ntawm ntau yam, ib qho tseem ceeb tshaj plaws yog cov ntsiab lus hydroxypropyl. Ntxiv nrog rau cov ntsiab lus hydroxypropyl, lwm yam uas cuam tshuam rau gel kub muaj xws li molecular hnyav, kev daws teeb meem, pH nqi, hnyav hom, ionic zog, thiab lwm yam.
3. Cov nyhuv ntawm hydroxypropyl cov ntsiab lus ntawm HPMC gel kub
3.1 Qhov nce hauv hydroxypropyl cov ntsiab lus ua rau muaj kev nce hauv gel kub
Lub gelation kub ntawm HPMC yog ze ze rau qib ntawm hydroxypropyl hloov pauv hauv nws cov molecule. Raws li cov ntsiab lus hydroxypropyl nce, tus naj npawb ntawm hydrophilic hloov pauv ntawm HPMC cov saw hlau molecular nce, uas ua rau muaj kev sib raug zoo ntawm cov molecule thiab dej. Qhov kev cuam tshuam no ua rau cov saw hlau molecular txuas ntxiv, yog li txo lub zog ntawm kev sib cuam tshuam ntawm cov saw hlau molecular. Nyob rau hauv ib qho kev concentration ntau, nce cov ntsiab lus hydroxypropyl pab txhim kho qib ntawm hydration thiab txhawb kev sib koom ua ke ntawm cov saw hlau molecular, kom lub network qauv tuaj yeem tsim ntawm qhov kub siab dua. Yog li, gelation kub feem ntau nce nrog hydroxypropyl nce nrog nce cov ntsiab lus.
HPMC uas muaj cov ntsiab lus hydroxypropyl ntau dua (xws li HPMC K15M) nyiam ua kom pom qhov kub thiab txias ntawm tib qhov concentration dua li AnxinCel®HPMC nrog cov ntsiab lus hydroxypropyl qis (xws li HPMC K4M). Qhov no yog vim hais tias cov ntsiab lus hydroxypropyl ntau dua ua rau nws nyuaj rau cov molecules sib cuam tshuam thiab tsim cov tes hauj lwm ntawm qhov kub thiab txias, yuav tsum tau kub siab dua kom kov yeej cov dej no thiab txhawb kev sib cuam tshuam ntawm cov khoom siv los tsim cov qauv peb sab. .
3.2 Kev sib raug zoo ntawm hydroxypropyl cov ntsiab lus thiab kev daws teeb meem
Kev daws teeb meem kuj yog ib qho tseem ceeb cuam tshuam rau qhov kub thiab txias ntawm HPMC. Hauv cov ntsiab lus siab ntawm HPMC cov kev daws teeb meem, cov kev sib cuam tshuam ntawm intermolecular muaj zog dua, yog li qhov kub ntawm gelation yuav siab dua txawm tias cov ntsiab lus hydroxypropyl qis dua. Ntawm qhov tsis tshua muaj siab, kev sib cuam tshuam ntawm HPMC cov molecules tsis muaj zog, thiab cov kev daws teeb meem feem ntau yog gel ntawm qhov kub thiab txias.
Thaum cov ntsiab lus hydroxypropyl nce, txawm hais tias qhov hydrophilicity nce, qhov kub siab dua tseem yuav tsum tau tsim cov gel. Tshwj xeeb tshaj yog nyob rau hauv qis concentration tej yam kev mob, lub gelation kub nce ntau ho. Qhov no yog vim HPMC nrog cov ntsiab lus siab hydroxypropyl yog qhov nyuaj rau kev sib cuam tshuam ntawm cov saw hlau molecular los ntawm kev hloov pauv kub, thiab cov txheej txheem gelation yuav tsum muaj lub zog thermal ntxiv kom kov yeej cov nyhuv dej.
3.3 Cov nyhuv ntawm hydroxypropyl cov ntsiab lus ntawm cov txheej txheem gelation
Nyob rau hauv ib tug tej yam ntau yam ntawm hydroxypropyl cov ntsiab lus, cov txheej txheem gelation yog dominated los ntawm kev sib cuam tshuam ntawm hydration thiab molecular chains. Thaum cov ntsiab lus hydroxypropyl nyob rau hauv HPMC molecule qis, cov dej tsis muaj zog, kev sib cuam tshuam ntawm cov molecules muaj zog, thiab qhov kub qis tuaj yeem txhawb kev tsim cov gel. Thaum cov ntsiab lus hydroxypropyl siab dua, cov dej muaj zog tau txhim kho, kev sib cuam tshuam ntawm cov saw hlau molecular yuav tsis muaj zog, thiab cov gelation kub nce.
Cov ntsiab lus hydroxypropyl siab dua kuj tseem tuaj yeem ua rau nce qhov viscosity ntawm HPMC cov tshuaj, qhov kev hloov pauv uas qee zaum ua rau qhov pib kub ntawm gelation.
Hydroxypropyl cov ntsiab lus muaj qhov cuam tshuam loj rau qhov kub ntawm gelationHPMC. Raws li cov ntsiab lus hydroxypropyl nce, hydrophilicity ntawm HPMC nce thiab kev cuam tshuam ntawm cov saw hlau molecular tsis muaj zog, yog li nws qhov kub thiab txias feem ntau nce. Qhov tshwm sim no tuaj yeem piav qhia los ntawm kev sib cuam tshuam mechanism ntawm hydration thiab molecular chains. Los ntawm kev kho cov ntsiab lus hydroxypropyl ntawm HPMC, kev tswj xyuas meej ntawm gelation kub tuaj yeem ua tiav, yog li kev ua kom zoo ntawm HPMC hauv kev siv tshuaj, khoom noj thiab lwm yam kev lag luam.
Post lub sij hawm: Jan-04-2025