Hydroxypropyl methylcellulose (HPMC) yog ib qho polymer uas siv tau ntau yam thiab siv dav hauv ntau yam lag luam, paub txog nws cov yam ntxwv tshwj xeeb thiab kev siv. Cov tshuaj no yog ib qho derivative ntawm cellulose, ib qho polymer ntuj pom muaj nyob rau hauv cov phab ntsa cell ntawm cov nroj tsuag. Yuav kom nkag siab txog cov khoom sib xyaw ntawm hydroxypropylmethylcellulose, nws yog ib qho tsim nyog los nkag siab txog cov qauv thiab kev tsim cov cellulose derivative no.
Cov qauv ntawm cellulose:
Cellulose yog ib hom carbohydrate uas muaj cov saw hlau β-D-glucose uas txuas nrog los ntawm β-1,4-glycosidic bonds. Cov saw hlau glucose no raug tuav ua ke los ntawm hydrogen bonds los ua ib qho qauv linear. Cellulose yog cov khoom tseem ceeb ntawm cov phab ntsa cell ntawm cov nroj tsuag, muab lub zog thiab kev ruaj khov rau cov nroj tsuag cell.
Cov khoom xyaw ntawm Hydroxypropyl Methylcellulose:
Hydroxypropyl methylcellulose yog tsim los ntawm kev hloov kho cellulose thiab qhia hydroxypropyl thiab methyl pawg rau hauv cov saw tseem ceeb ntawm cellulose. Kev tsim khoom feem ntau suav nrog cov kauj ruam hauv qab no:
Kev ua haujlwm ntawm Etherification:
Methylation: Kho cov cellulose nrog cov kua alkaline thiab methyl chloride los qhia cov pawg methyl (-CH3) rau hauv cov pawg hydroxyl (-OH) ntawm cellulose.
Hydroxypropylation: Methylated cellulose ntxiv reacts nrog propylene oxide los qhia hydroxypropyl pawg (-CH2CHOHCH3) rau hauv cov qauv cellulose. Cov txheej txheem no ua rau cov dej yaj thiab hloov cov khoom ntawm cellulose.
kev ntxuav:
Cov cellulose hloov kho ces raug ntxuav kom tshem tawm cov tshuaj reagents, by-products lossis impurities uas tsis tau ua haujlwm.
Kev ziab thiab kev sib tsoo:
Cov hydroxypropyl methylcellulose uas tau lim lawm yog qhuav thiab zom ua hmoov zoo npaj rau kev siv rau ntau yam kev siv.
Cov khoom xyaw ntawm Hydroxypropyl Methylcellulose:
Cov khoom sib xyaw ntawm hydroxypropyl methylcellulose yog tus cwj pwm los ntawm qib kev hloov pauv, uas yog hais txog qib uas hydroxypropyl thiab methyl pawg hloov cov pab pawg hydroxyl hauv cov saw cellulose. Cov qib sib txawv ntawm HPMC muaj qib sib txawv ntawm kev hloov pauv, cuam tshuam rau lawv cov solubility, viscosity thiab lwm yam khoom.
Cov mis tshuaj ntawm hydroxypropyl methylcellulose tuaj yeem qhia ua (C6H7O2(OH)3-mn(OCH3)m(OCH2CH(OH)CH3)n)_x, qhov twg m thiab n sawv cev rau qib kev hloov pauv.
m: qib ntawm methylation (methyl pawg ib chav glucose)
n: qib ntawm hydroxypropylation (hydroxypropyl pawg ib chav glucose)
x: tus naj npawb ntawm cov chav glucose hauv cov saw cellulose
Nta thiab Daim Ntawv Thov:
Kev yaj tau: HPMC yaj tau hauv dej, thiab qib kev hloov pauv cuam tshuam rau nws cov yam ntxwv yaj tau. Nws tsim cov kua ntshiab thiab khov hauv dej, ua rau nws haum rau ntau yam qauv.
Viscosity: Qhov viscosity ntawm HPMC kua nyob ntawm cov yam xws li qhov hnyav molecular thiab qib ntawm kev hloov pauv. Cov khoom no yog qhov tseem ceeb rau cov ntawv thov xws li tshuaj uas xav tau cov qauv tso tawm tswj.
Kev Tsim Zaj Duab Xis: HPMC tuaj yeem tsim cov zaj duab xis nyias thaum cov tshuaj qhuav, ua rau nws muaj txiaj ntsig zoo hauv kev pleev xim hauv kev lag luam tshuaj, khoom noj thiab lwm yam lag luam.
Cov Khoom Ruaj Khoov thiab Cov Khoom Ua Kom Tuab: Hauv kev lag luam zaub mov, HPMC yog siv los ua cov khoom ua kom tuab thiab cov khoom ruaj khov hauv ntau yam khoom, suav nrog cov kua ntses, khoom qab zib, thiab cov khoom ci.
Cov Ntawv Thov Tshuaj: HPMC siv dav hauv cov tshuaj tsim, suav nrog cov ntsiav tshuaj, tshuaj ntsiav, thiab cov tshuaj ophthalmic, vim nws cov khoom tso tawm tswj tau thiab biocompatibility.
Kev Tsim Kho thiab Txheej Txheem: HPMC siv rau hauv cov ntaub ntawv tsim kho xws li cov xuab zeb, cov nplaum pobzeb thiab cov plasters. Nws kuj tseem siv ua cov khoom ua kom tuab thiab ruaj khov hauv cov xim thiab cov txheej txheem txheej txheem.
Cov Khoom Siv Saib Xyuas Tus Kheej: Hauv kev lag luam tshuaj pleev ib ce thiab kev saib xyuas tus kheej, HPMC pom muaj nyob rau hauv cov khoom xws li tshuaj pleev, tshuaj pleev thiab tshuaj zawv plaub hau, qhov twg nws muab cov qauv thiab kev ruaj khov.
Hydroxypropyl methylcellulose tau los ntawm methylation thiab hydroxypropylation ntawm cellulose. Nws yog ib qho polymer ntau lub hom phiaj nrog ntau yam kev siv. Nws cov yam ntxwv tshwj xeeb ua rau nws muaj txiaj ntsig zoo hauv kev lag luam xws li tshuaj, khoom noj, kev tsim kho thiab kev saib xyuas tus kheej. Kev hloov kho cellulose tswj tau tuaj yeem kho cov yam ntxwv ntawm HPMC, ua rau nws yog ib qho tseem ceeb ntawm ntau yam khoom uas peb ntsib hauv peb lub neej txhua hnub.
Lub sijhawm tshaj tawm: Lub Ib Hlis-10-2024