1.Hydroxypropyl methylcellulose (HPMC)yog ib qho tseem ceeb ntawm cellulose ether, dav siv hauv kev tsim kho, tshuaj, khoom noj, tshuaj pleev ib ce thiab lwm yam. HPMC muaj cov thickening zoo, film-forming, emulsifying, suspension thiab dej tuav cov khoom, yog li nws plays lub luag hauj lwm tseem ceeb nyob rau hauv ntau yam lag luam. Kev tsim tawm ntawm HPMC feem ntau yog nyob ntawm kev hloov kho tshuaj lom neeg. Nyob rau hauv xyoo tas los no, nrog rau kev nce qib ntawm biotechnology, kev tsim khoom raws li microbial fermentation kuj tau pib nyiam.
2. Fermentation ntau lawm txoj cai ntawm HPMC
Cov txheej txheem HPMC cov txheej txheem tsim khoom siv natural cellulose ua raw khoom thiab yog tsim los ntawm kev siv tshuaj xws li alkalization, etherification thiab refining. Txawm li cas los xij, cov txheej txheem no suav nrog ntau cov organic solvents thiab tshuaj reagents, uas muaj kev cuam tshuam zoo rau ib puag ncig. Yog li ntawd, kev siv cov microbial fermentation los ua ke cellulose thiab ntxiv etherify nws tau dhau los ua ib tug ntau tus phooj ywg environmentally thiab sustainable ntau lawm txoj kev.
Microbial synthesis ntawm cellulose (BC) yog lub ntsiab lus kub hauv xyoo tas los no. Cov kab mob xws li Komagataeibacter (xws li Komagataeibacter xylinus) thiab Gluconacetobacter tuaj yeem ncaj qha tsim cov cellulose purity siab los ntawm fermentation. Cov kab mob no siv cov piam thaj, glycerol lossis lwm cov pa roj carbon monoxide ua substrates, ferment nyob rau hauv cov xwm txheej tsim nyog, thiab tso cov cellulose nanofibers. Qhov tshwm sim ntawm cov kab mob cellulose tuaj yeem hloov mus rau hauv HPMC tom qab hloov kho hydroxypropyl thiab methylation.
3. Cov txheej txheem ntau lawm
3.1 Cov txheej txheem fermentation ntawm cov kab mob cellulose
Kev ua kom zoo ntawm cov txheej txheem fermentation yog qhov tseem ceeb rau kev txhim kho cov qoob loo thiab zoo ntawm cov kab mob cellulose. Cov kauj ruam tseem ceeb yog raws li nram no:
Kev tshuaj ntsuam xyuas thiab kev cog qoob loo: Xaiv cov txiaj ntsig zoo ntawm cov cellulose, xws li Komagataeibacter xylinus, rau kev ua liaj ua teb thiab kev ua kom zoo.
Fermentation nruab nrab: Muab cov pa roj carbon (qabzib, sucrose, xylose), nitrogen qhov chaw (cov poov xab extract, peptone), inorganic ntsev (phosphates, magnesium ntsev, thiab lwm yam) thiab regulators (acetic acid, citric acid) los txhawb cov kab mob loj hlob thiab cellulose synthesis.
Fermentation mob tswj: suav nrog kub (28-30 ℃), pH (4.5-6.0), yaj cov pa oxygen (cuam tshuam lossis kab lis kev cai zoo li qub), thiab lwm yam.
Kev sau thiab ua kom huv: Tom qab fermentation, cov kab mob cellulose tau sau los ntawm kev lim, ntxuav, ziab thiab lwm cov kauj ruam, thiab cov kab mob seem thiab lwm yam impurities raug tshem tawm.
3.2 Hydroxypropyl methylation hloov kho ntawm cellulose
Cov kab mob uas tau txais cov cellulose yuav tsum tau hloov kho los muab nws cov yam ntxwv ntawm HPMC. Cov kauj ruam tseem ceeb yog raws li nram no:
Kev kho alkalinization: soak hauv qhov tsim nyog ntawm NaOH cov tshuaj kom nthuav cov cellulose thiab txhim kho cov tshuaj tiv thaiv kev ua haujlwm ntawm etherification tom ntej.
Cov tshuaj tiv thaiv Etherification: nyob rau hauv qhov kub thiab txias thiab catalytic tej yam kev mob, ntxiv propylene oxide (hydroxypropylation) thiab methyl chloride (methylation) los hloov cov cellulose hydroxyl pawg los tsim HPMC.
Neutralization thiab refining: neutralize nrog acid tom qab cov tshuaj tiv thaiv kom tshem tawm cov tshuaj reagents unreacted, thiab tau txais cov khoom kawg los ntawm kev ntxuav, lim thiab ziab.
Crushing thiab muab qhab nia: tsoo HPMC rau hauv cov khoom uas ua tau raws li qhov tshwj xeeb, thiab tshuaj ntsuam thiab ntim lawv raws li qib viscosity sib txawv.
4. Cov thev naus laus zis tseem ceeb thiab cov tswv yim ua kom zoo
Kev txhim kho cov kab mob: txhim kho cellulose tawm los thiab zoo los ntawm kev tsim cov noob caj noob ces ntawm cov kab mob microbial.
Fermentation txheej txheem optimization: siv bioreactors rau dynamic tswj los txhim kho cellulose ntau lawm efficiency.
Green etherification txheej txheem: txo cov kev siv cov kuab tshuaj organic thiab txhim kho ib puag ncig tus phooj ywg etherification technologies, xws li enzyme catalytic hloov kho.
Kev tswj cov khoom zoo: los ntawm kev txheeb xyuas qhov hloov pauv, solubility, viscosity thiab lwm yam ntsuas ntawm HPMC, xyuas kom meej tias nws ua tau raws li daim ntawv thov.
Cov fermentation-raws liHPMCtxoj kev tsim khoom muaj qhov zoo ntawm kev rov ua dua tshiab, ib puag ncig tus phooj ywg thiab ua haujlwm tau zoo, uas yog nyob rau hauv txoj kab nrog cov qauv ntawm ntsuab chemistry thiab kev tsim kho kom ruaj khov. Nrog rau kev nce qib ntawm biotechnology, cov thev naus laus zis no yuav tsum maj mam hloov cov txheej txheem tshuaj ib txwm siv thiab txhawb nqa kev siv dav dav ntawm HPMC hauv kev tsim kho, khoom noj, tshuaj, thiab lwm yam.
Lub sij hawm xa tuaj: Plaub Hlis-11-2025