Kev tsim cov txheej txheem ntawm sodium carboxymethylcellulose

Kev tsim cov txheej txheem ntawm sodium carboxymethylcellulose (CMC) muaj ob peb kauj ruam, nrog rau kev npaj ntawm cellulose, etherification, purification, thiab ziab. Ntawm no yog ib qho kev piav qhia ntawm cov txheej txheem tsim khoom ib txwm:

1. Kev npaj ntawm Cellulose: Cov txheej txheem pib nrog kev npaj ntawm cellulose, uas feem ntau yog los ntawm cov ntoo pulp lossis paj rwb linters. Cov cellulose yog thawj zaug purified thiab refined kom tshem tawm impurities xws li lignin, hemicellulose, thiab lwm yam kab mob. Qhov no purified cellulose ua cov khoom pib rau kev tsim CMC.
2. Alkalization: Cov purified cellulose yog tom qab ntawd kho nrog cov tshuaj alkaline, feem ntau yog sodium hydroxide (NaOH), kom nws reactivity thiab pab txhawb cov etherification cov tshuaj tiv thaiv tom ntej. Alkalization kuj pab kom o thiab qhib cov cellulose fibers, ua rau lawv yooj yim dua rau kev hloov kho tshuaj.
3. Etherification Reaction: Lub alkalized cellulose yog reacted nrog monochloroacetic acid (MCA) los yog nws cov ntsev ntsev, sodium monochloroacetate (SMCA), nyob rau hauv lub xub ntiag ntawm ib tug catalyst nyob rau hauv kev tswj tej yam kev mob. Cov tshuaj tiv thaiv etherification no suav nrog kev hloov pauv ntawm pawg hydroxyl ntawm cov cellulose chains nrog carboxymethyl (-CH2COONa) pawg. Qhov degree ntawm kev hloov pauv (DS), uas sawv cev rau qhov nruab nrab ntawm cov carboxymethyl pawg ib cov piam thaj hauv cellulose, tuaj yeem tswj tau los ntawm kev kho cov tshuaj tiv thaiv xws li qhov kub thiab txias, lub sijhawm tshuaj tiv thaiv, thiab cov tshuaj reactant concentrations.
4. Neutralization: Tom qab cov tshuaj tiv thaiv etherification, cov khoom tsim tawm yog nruab nrab los hloov cov pab pawg acidic ntxiv rau lawv daim ntawv ntsev ntsev (carboxymethylcellulose sodium). Qhov no feem ntau ua tiav los ntawm kev ntxiv cov tshuaj alkaline, xws li sodium hydroxide (NaOH), rau cov tshuaj tiv thaiv sib tov. Neutralization kuj pab kho pH ntawm cov tshuaj thiab stabilize CMC cov khoom.
5. Purification: Lub crude sodium carboxymethylcellulose ces purified kom tshem tawm impurities, unreacted reagents, thiab by-products los ntawm cov tshuaj tiv thaiv sib tov. purification txoj kev yuav muaj xws li ntxuav, pom, centrifugation, thiab ziab. CMC purified feem ntau yog ntxuav nrog dej kom tshem tawm cov seem alkali thiab ntsev, ua raws li kev pom los yog centrifugation kom cais cov khoom CMC los ntawm cov kua theem.
6. Kev ziab: Cov purified sodium carboxymethylcellulose thaum kawg qhuav kom tshem tawm cov dej noo ntau dhau thiab tau txais cov ntsiab lus noo noo xav tau rau kev khaws cia thiab ua haujlwm ntxiv. Txoj kev ziab tuaj yeem suav nrog huab cua kom qhuav, tshuaj tsuag kom qhuav, lossis ziab ziab, nyob ntawm seb cov khoom xav tau thiab cov khoom lag luam.

Cov txiaj ntsig sodium carboxymethylcellulose cov khoom lag luam yog cov hmoov dawb dawb los yog cov khoom siv granular nrog cov dej solubility zoo heev thiab cov khoom siv rheological. Nws yog dav siv los ua tus neeg sawv cev thickening, stabilizer, binder, thiab rheology modifier nyob rau hauv ntau yam lag luam, nrog rau cov khoom noj, tshuaj, tshuaj pleev ib ce, textiles, thiab kev lag luam.