Methylcellulose (MC) yog ib yam khoom siv polymer uas siv tshuaj lom neeg, uas yog ib qho cellulose ether uas tau los ntawm kev methylating cov cellulose ntuj. Vim nws cov khoom tshwj xeeb thiab cov tshuaj lom neeg, nws yog siv dav hauv kev tsim kho, khoom noj, tshuaj, tshuaj pleev ib ce, ntawv thiab txheej.
1. Kev faib tawm los ntawm qib kev hloov pauv
Qhov degree of substitution (DS) yog hais txog tus nqi nruab nrab ntawm cov hydroxyl pawg uas tau hloov los ntawm methyl pawg ntawm txhua chav glucose hauv methylcellulose. Muaj 3 pawg hydroxyl ntawm txhua lub nplhaib glucose ntawm cellulose molecule uas tuaj yeem hloov los ntawm methyl pawg. Yog li ntawd, qhov degree ntawm kev hloov pauv ntawm methylcellulose tuaj yeem sib txawv ntawm 0 txog 3. Raws li degree ntawm kev hloov pauv, methylcellulose tuaj yeem faib ua ob pawg: qib siab ntawm kev hloov pauv thiab qib qis ntawm kev hloov pauv.
Qib siab ntawm kev hloov pauv methylcellulose (DS > 1.5): Hom khoom no muaj qib siab ntawm kev hloov pauv methyl, yog li nws yog hydrophobic ntau dua, muaj qhov solubility qis dua thiab tiv taus dej zoo. Nws feem ntau yog siv rau hauv cov ntaub ntawv tsim kho, txheej thiab lwm yam xwm txheej uas xav tau qee qib ntawm hydrophobicity.
Qib qis ntawm kev hloov pauv methylcellulose (DS < 1.5): Vim muaj kev hloov pauv methyl tsawg dua, hom khoom no yog hydrophilic ntau dua, muaj kev yaj zoo dua thiab tuaj yeem yaj hauv dej txias. methylcellulose uas muaj kev hloov pauv qis yog siv dav hauv kev lag luam khoom noj thiab tshuaj ua cov khoom ua kom tuab, emulsifier thiab stabilizer.
2. Kev faib tawm los ntawm kev siv
Raws li kev siv methylcellulose hauv ntau qhov chaw sib txawv, nws tuaj yeem muab faib ua ob pawg: kev lag luam methylcellulose thiab khoom noj thiab tshuaj methylcellulose.
Kev lag luam methylcellulose: Feem ntau siv rau hauv kev tsim kho, kev pleev xim, kev ua ntawv, kev ua av nplaum thiab lwm yam lag luam ua cov khoom ua kom tuab, cov nplaum, cov khoom ua zaj duab xis, cov neeg sawv cev khaws dej, thiab lwm yam. Hauv kev lag luam kev tsim kho, methylcellulose siv rau hauv cov khoom cement thiab gypsum los txhim kho kev ua haujlwm ntawm kev tsim kho thiab kev ruaj khov; hauv kev lag luam pleev xim, methylcellulose tuaj yeem ua rau kom muaj kev ruaj khov thiab kev sib kis ntawm cov xim pleev xim.
Khoom noj thiab tshuaj methylcellulose: Vim nws cov khoom tsis muaj tshuaj lom thiab tsis muaj teeb meem, methylcellulose yog siv los ua cov khoom ntxiv rau hauv khoom noj thiab tshuaj. Hauv khoom noj, methylcellulose yog ib qho khoom ua kom tuab thiab emulsifier uas tuaj yeem ua kom cov qauv khoom noj ruaj khov thiab tiv thaiv kev faib ua pawg lossis kev sib cais; hauv kev lag luam tshuaj, methylcellulose tuaj yeem siv ua lub plhaub tshuaj ntsiav, lub thawv tshuaj, thiab tseem muaj lub luag haujlwm ntawm cov tshuaj tso tawm tas mus li. Nws qhov kev noj tau thiab kev nyab xeeb ua rau methylcellulose nrov heev hauv ob qho teb no.
3. Kev faib tawm los ntawm kev yaj
Methylcellulose feem ntau muab faib ua ob pawg raws li kev yaj: hom dej txias soluble thiab hom organic solvent soluble.
Cov methylcellulose uas yaj tau hauv dej txias: Hom methylcellulose no tuaj yeem yaj rau hauv dej txias kom ua tau cov kua pob tshab, nplaum tom qab yaj. Nws feem ntau siv rau hauv kev lag luam khoom noj thiab tshuaj ua cov khoom ua kom tuab lossis cov zaj duab xis. Qhov kev yaj ntawm hom methylcellulose no txo qis nrog rau qhov kub nce ntxiv, yog li qhov no tuaj yeem siv rau kev tswj kev tsim kho thaum siv hauv kev lag luam kev tsim kho.
Cov tshuaj methylcellulose uas yaj tau hauv cov organic solvent: Hom methylcellulose no tuaj yeem yaj tau hauv cov organic solvents thiab feem ntau siv rau hauv cov xim pleev xim, cov tshuaj pleev xim thiab lwm yam kev lag luam uas xav tau cov organic phase media. Vim nws cov khoom zoo rau kev tsim cov zaj duab xis thiab kev tiv taus tshuaj lom neeg, nws tsim nyog siv rau hauv cov xwm txheej kev lag luam hnyav.
4. Kev faib tawm los ntawm qhov hnyav molecular (viscosity)
Qhov hnyav molecular ntawm methylcellulose muaj feem cuam tshuam loj heev rau nws cov khoom siv lub cev, tshwj xeeb tshaj yog qhov ua tau zoo ntawm viscosity hauv cov tshuaj. Raws li qhov hnyav molecular, methylcellulose tuaj yeem muab faib ua hom viscosity qis thiab hom viscosity siab.
Cov methylcellulose uas tsis muaj viscosity ntau: Qhov hnyav molecular me me thiab cov viscosity ntawm cov tshuaj kuj tsawg. Nws feem ntau siv rau hauv cov khoom noj, tshuaj thiab tshuaj pleev ib ce, feem ntau yog rau kev emulsification, kev ncua thiab kev tuab. Cov methylcellulose uas tsis muaj viscosity ntau tuaj yeem tswj tau qhov fluidity thiab uniformity zoo, thiab tsim nyog rau cov ntawv thov uas xav tau cov tshuaj uas tsis muaj viscosity ntau.
Methylcellulose uas muaj viscosity siab: Nws muaj qhov hnyav molecular loj thiab tsim cov kua viscosity siab tom qab yaj. Nws feem ntau siv rau hauv cov ntaub ntawv tsim kho, cov tshuaj pleev xim thiab cov nplaum rau kev lag luam. Methylcellulose uas muaj viscosity siab tuaj yeem ua rau lub zog kho tshuab, kev tiv thaiv kev hnav thiab kev nplaum ntawm cov kua, yog li nws siv dav hauv cov ntaub ntawv uas xav tau lub zog siab thiab kev tiv thaiv kev hnav siab.
5. Kev faib tawm los ntawm qib kev hloov pauv tshuaj lom neeg
Methylcellulose yog ib qho cellulose derivative uas tau hloov kho los ntawm tshuaj lom neeg. Raws li txoj kev hloov kho thiab qib, nws muaj peev xwm muab faib ua ib qho methyl cellulose thiab cov cellulose hloov kho sib xyaw.
Ib qho methyl cellulose: hais txog cov cellulose ethers uas tsuas yog methyl-substituted. Hom khoom no muaj cov khoom siv lub cev thiab tshuaj lom neeg ruaj khov, thiab nws cov khoom solubility, thickening thiab zaj duab xis-tsim yog qhov zoo.
Cov cellulose uas tau hloov kho ua ke: Ntxiv rau methylation, nws tseem raug kho los ntawm tshuaj lom neeg ntxiv, xws li hydroxypropylation, ethylation, thiab lwm yam, los tsim cov khoom hloov kho ua ke. Piv txwv li, hydroxypropyl methylcellulose (HPMC) thiab carboxymethyl cellulose (CMC). Cov cellulose uas tau hloov kho ua ke no feem ntau muaj kev yaj dej zoo dua, tiv taus cua sov thiab ruaj khov dua, thiab tuaj yeem hloov kho rau ntau yam kev xav tau ntawm kev lag luam.
6. Kev faib tawm los ntawm kev lag luam thov
Daim ntawv thov dav dav ntawm methylcellulose tso cai rau nws kom raug cais raws li nws cov yam ntxwv ntawm daim ntawv thov hauv ntau yam lag luam.
Kev lag luam kev tsim kho methylcellulose: Feem ntau siv rau hauv cov ntaub ntawv ua los ntawm cement thiab gypsum ua cov khoom khaws dej thiab ua kom tuab. Nws tuaj yeem txhim kho kev ua haujlwm ntawm cov ntaub ntawv tsim kho, tiv thaiv kev poob dej thaum ntxov, thiab ua kom lub zog ntawm cov khoom tiav.
Kev lag luam zaub mov methylcellulose: Ua ib qho emulsifier, thickener thiab stabilizer hauv kev ua zaub mov. Nws tuaj yeem tiv thaiv kev poob dej, txhim kho qhov saj thiab cov qauv ntawm cov zaub mov, thiab ua kom cov zaub mov nyob ntev dua.
Kev lag luam tshuaj methylcellulose: Ua ib qho khoom siv khi rau cov ntsiav tshuaj lossis cov khoom siv tso tawm ntev rau cov tshuaj. Methylcellulose kuj tseem siv tau rau hauv kev npaj cov tshuaj gastrointestinal ua ib qho chaw nqa tshuaj uas muaj kev nyab xeeb thiab zoo.
Kev lag luam tshuaj pleev ib ce methylcellulose: Hauv cov khoom siv tu tawv nqaij thiab tshuaj pleev ib ce, methylcellulose yog siv los ua cov khoom ua kom tuab, emulsifier thiab moisturizer los pab cov khoom tsim cov qauv mos thiab du thaum lub sijhawm ntev cov nyhuv moisturizing.
Hauv kev xaus, muaj ntau txoj hauv kev los faib cov methylcellulose, uas tuaj yeem faib raws li nws cov yam ntxwv ntawm cov qauv tshuaj, lossis raws li nws cov teb thov thiab cov khoom solubility. Cov txheej txheem faib sib txawv no pab peb nkag siab zoo dua txog cov yam ntxwv thiab kev ua haujlwm ntawm methylcellulose, thiab tseem muab lub hauv paus theoretical rau nws daim ntawv thov hauv ntau qhov chaw.
Lub sijhawm tshaj tawm: Lub Kaum Hli-23-2024