HydroxyPropyyl Methylcellulose (HPMC) yog ib feem siv dej-soluble polymer, siv dav hauv cov tshuaj, tshuaj pleev ib ce, khoom noj khoom haus, tshwj xeeb tshaj yog nyob rau hauv kev npaj cov gels. Nws cov khoom siv lub cev thiab cov cwj pwm xaus tau muaj kev cuam tshuam tseem ceeb ntawm kev ua tau zoo hauv cov ntawv thov sib txawv. Lub gelation kub ntawm HPMC gel yog ib qho ntawm nws cov peev txheej ntawm lub cev, uas cuam tshuam ncaj qha rau nws txoj kev npaj, ua yeeb yaj kiab, kev ruaj khov, thiab lwm yam.
1. Cov qauv thiab cov khoom ntawm HPMC
HPMC yog dej-soluble polymer tau los ntawm kev qhia ob qho chaw, hydroxypropyl thiab methyl, rau hauv lub cellulose molecular pob txha taub hau. Nws cov qauv molecular muaj ob hom hloov chaw: hydroxypropyl (-ch2chohch3) thiab methyl (-ch3). Yam khoom xws li cov ntsiab lus hydroxypropyl sib txawv, Qib ntawm polymerization, thiab cov kev coj ua tseem ceeb rau HPMC.
Nyob rau hauv cov kev daws teeb meem aqueous, txhawjpluaj cov ntaub ntawv ruaj khov los ntawm kev ua cov lwg hydrogen nrog cov roj av molecules thiab cuam tshuam nrog nws cov cellulose-raws li pob txha. Thaum ib puag ncig sab nraud (xws li qhov ntsuas kub sab nraud (xws li qhov ntsuas kub, thiab lwm yam) hloov pauv, kev sib cuam tshuam ntawm HPMC Molecules yuav hloov pauv, ua rau muaj kev sib tw.
2. Kev txhais thiab cuam tshuam cov ntsiab lus ntawm gelation kub
Gelation kub (gelation kub, t_gel) yog hais txog qhov kub ntawm qhov kev hloov pauv ntawm cov kua rau cov khoom siv thaum kub thiab kub nce mus rau ib theem. Ntawm qhov kub no, kev txav ntawm HPMC molecular chains yuav raug txwv, tsim ib tug qauv sib tw, ua rau cov khoom siv gel zoo li.
Lub gelation ntsuas kub ntawm HPMC cuam tshuam los ntawm ntau yam, ib qho tseem ceeb tshaj plaws yog cov ntsiab lus hydroxypropylopyl. Ntxiv nrog rau hydroxypropyl cov ntsiab lus, lwm yam uas cuam tshuam nrog kev kub ntxhov, kev daws teeb meem, siv lub zog Ph Phaj, ionic lub zog, thiab lwm yam.
3. Cov nyhuv ntawm hydroxypropyl cov ntsiab lus ntawm HPMC gel kub
3.1 Qhov nce nyob rau 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 hauv nws cov molecule. Raws li cov ntsiab lus hydroxypropyl nce, tus naj npawb ntawm hydrophilic hloov chaw nyob rau HPMC molecular saw nce ntxiv, ua rau muaj kev cuam tshuam zoo ntawm cov molecule thiab dej. Qhov kev sib txuam no ua rau cov molecular chains kom ncab ntxiv, yog li txo lub zog ntawm kev sib cuam tshuam ntawm cov molecular chains. Tsis pub dhau qee yam kev xav tau ntau yam, nce cov ntsiab lus hydroxypropyl tau pab txhim kho kev sib nrig sib pab ntawm cov qauv molecular, kom cov qauv network tuaj yeem tsim tau ntawm qhov kub siab dua. Yog li ntawd, qhov gelation kub feem ntau nce nrog hydroxypropyl sawv nrog kev nce cov ntsiab lus.
HPMC nrog ntau dua Hydroxypropyl cov ntsiab lus (xws li HPMC K15M) nyiam ua kom muaj kev ntxhov siab ntau dua li hydroxypropyl cov ntsiab lus (xws li HPMC K4M). Qhov no yog vim muaj ntau dua hydroxypropyl cov ntsiab lus ua rau nws nyuaj rau kev cuam tshuam rau kev kub ntxhov thiab tsim cov kev sib txuas lus hauv qab no thiab kev sib txuas lus sib xyaw ua ke. Cov.
3.2 Kev sib raug zoo ntawm hydroxypropyl cov ntsiab lus thiab kev daws teeb meem
Kev daws teeb meem tseem yog qhov tseem ceeb cuam tshuam rau kev nkag siab kub ntawm HPMC. Hauv kev txhim kho HPMC, cov kev sib txuam sib xyaw muaj zog dua, yog li cov gelation kub yuav siab dua yog tias cov ntsiab lus hydroxypropylopyl yog qis dua. Thaum tsis tshua muaj ntau, kev sib cuam tshuam ntawm HPMC lwg me me tsis muaj zog, thiab kev daws teeb meem yog cov gel ntau dua.
Thaum hydroxypropyl cov ntsiab lus nce, txawm hais tias hydrophilicity nce, kub siab dua yog tseem yuav tsum tau ua tus gel. Tshwj xeeb tshaj yog nyob rau hauv qis kev kub siab, kev gelation kub nce ntau dua. Qhov no yog vim HPMC nrog cov ntsiab lus hydroxypropyl yog qhov nyuaj rau kev cuam tshuam ntawm cov kev sib txuas lus kub thiab txias kom siv zog ntxiv cov hydration nyhuv.
3.3 Cov nyhuv ntawm hydroxypropyl cov ntsiab lus ntawm cov txheej txheem gelation
Tsis pub dhau qee yam ntawm hydroxypropyl cov ntsiab lus, cov txheej txheem gelation yog yeej los ntawm kev sib cuam tshuam ntawm kev co thiab molecular chains. Thaum hydroxypropyl cov ntsiab lus hauv HPMC molecule yog tsawg, kev sib cuam tshuam ntawm cov lwg me me, thiab qhov kub qis tuaj yeem txhawb kev tsim cov gel. Thaum hydroxypropyl cov ntsiab lus siab dua, cov hydration yog txhim kho, kev sib cuam tshuam ntawm molecular chains ua tsis muaj zog, thiab kub kub nce.
Cov ntsiab lus hydroxypropyl kuj tseem yuav ua rau muaj kev daws teeb meem HPMC, qhov kev hloov uas qee zaum nce qhov kev kub ntxhov ntawm kev kub.
Hydroxypropyl cov ntsiab lus muaj qhov cuam tshuam tseem ceeb ntawm kev nkag siab kub ntawmHPMCCov. Raws li cov ntsiab lus hydroxypropyl nce, lub hydrophilicity ntawm HydmC nce thiab kev sib cuam tshuam ntawm molecular chains tsis muaj zog, yog li nws gelation kub feem ntau nce. Qhov kev tshwm sim no tuaj yeem piav qhia los ntawm kev sib txuam mechanism ntawm kev co dej thiab molecular chains. Los ntawm kho cov ntsiab lus hydroxypropyl ntawm Hydmc, kho kom haum ntawm kev ua tau zoo ntawm HPMC hauv cov ntaub ntawv thiab lwm yam kev siv khoom lag luam.
Lub Sijhawm Post: Jan-04-2025