Koj puas paub txog hypromellose?

Hydroxypropyl methylcellulose (INN lub npe: Hypromellose), kuj yooj yim raws li hypromellose (hydroxypropyl methylcellulose, abbreviated liHPMC), yog ntau hom nonionic cellulose sib xyaw ethers. Nws yog ib qho khoom siv hluav taws xob, tsis muaj zog, viscoelastic polymer feem ntau siv los ua cov roj nplua nyeem hauv ophthalmology, lossis ua cov khoom siv lossis cov khoom siv hauv qhov ncauj tshuaj, thiab feem ntau pom muaj nyob rau hauv ntau yam khoom lag luam.

Raws li cov khoom noj ntxiv, hypromellose tuaj yeem ua lub luag haujlwm hauv qab no: emulsifier, thickener, suspending agent thiab hloov tsiaj gelatin. Nws code (E-code) hauv Codex Alimentarius yog E464.

Chemical Properties:

Cov khoom tiav ntawmHydroxypropyl methylcellulose yog tsim los ntawm cov tshuajyog hmoov dawb los yog dawb xoob fibrous khoom, thiab cov particle loj dhau los ntawm 80-mesh sieve. Qhov piv ntawm cov ntsiab lus methoxyl rau cov ntsiab lus hydroxypropyl ntawm cov khoom tiav yog txawv, thiab cov viscosity txawv, yog li nws dhau los ua ntau yam nrog ntau yam kev ua yeeb yam. Nws muaj cov yam ntxwv ntawm soluble hauv dej txias thiab insoluble hauv dej kub zoo ib yam li methyl cellulose, thiab nws cov solubility hauv cov kuab tshuaj organic ntau tshaj li cov dej. Nws tuaj yeem yaj hauv anhydrous methanol thiab ethanol, thiab tseem tuaj yeem yaj hauv chlorinated hydrocarbons xws li dichloro methane, trichloroethane, thiab cov kuab tshuaj organic xws li acetone, isopropanol, thiab diacetone cawv. Thaum yaj hauv dej, nws yuav ua ke nrog dej molecules los ua ib qho colloid. Nws ruaj khov rau cov kua qaub thiab alkali, thiab tsis cuam tshuam rau thaj tsam ntawm pH = 2 ~ 12. Hypromellose, txawm tias tsis muaj tshuaj lom, yog flammable thiab reacts hnyav nrog oxidizing tus neeg sawv cev.

Lub viscosity ntawm HPMC cov khoom nce nrog qhov nce ntawm concentration thiab molecular hnyav, thiab thaum kub nce, nws viscosity pib txo. Thaum nws nce mus txog qhov ntsuas kub, qhov viscosity dheev nce thiab gelation tshwm sim. qhov siab ntawm. Nws cov tshuaj aqueous yog ruaj khov ntawm chav tsev kub, tshwj tsis yog tias nws tuaj yeem degraded los ntawm enzymes, thiab nws cov viscosity dav tsis muaj qhov tshwm sim degradation. Nws muaj cov khoom tshwj xeeb thermal gelation, zoo zaj duab xis-tsim zog thiab nto ua haujlwm.

Ua:

Tom qab cov cellulose raug kho nrog alkali, alkoxy anion tsim los ntawm deprotonation ntawm pawg hydroxyl tuaj yeem ntxiv propylene oxide los tsim hydroxypropyl cellulose ether; Nws kuj tseem tuaj yeem sib xyaw nrog methyl chloride los tsim methyl cellulose ether. Hydroxypropyl methylcellulose yog tsim thaum ob qho tib si tshwm sim ib txhij.

Siv:

Kev siv hydroxypropyl methylcellulose zoo ib yam li lwm cov cellulose ethers. Nws yog tsuas yog siv los ua dispersant, suspending agent, thickener, emulsifier, stabilizer thiab nplaum nyob rau hauv ntau yam teb. Nws yog superior rau lwm cov cellulose ethers nyob rau hauv cov nqe lus ntawm solubility, dispersibility, pob tshab thiab enzyme kuj.

Hauv kev lag luam khoom noj thiab tshuaj, nws yog siv los ua ib qho ntxiv. Nws yog siv los ua ib qho nplaum, thickener, dispersant, Emollient, stabilizer thiab emulsifier. Nws tsis muaj tshuaj lom, tsis muaj zaub mov muaj txiaj ntsig, thiab tsis muaj kev hloov pauv hauv metabolic.

Ntxiv rau,HPMCmuaj cov ntawv thov hauv cov khoom siv hluavtaws polymerization, petrochemicals, ceramics, papermaking, tawv, tshuaj pleev ib ce, coatings, cov ntaub ntawv hauv tsev thiab cov ntawv luam tawm photosensitive.