Methylcellulose (MC) thiab carboxymethylcelleculose (CMC) yog ob lub cellulose derivatives, siv cov zaub mov, kev tsim kho, kev lag luam tshuaj thiab lwm thaj chaw. Txawm hais tias lawv yog txhua tus tshuaj hloov kho los ntawm ntuj cellulose, muaj ntau qhov sib txawv hauv cov qauv tshuaj, lub cev thiab tshuaj lom neeg.
1. Cov qauv tshuaj lom neeg thiab cov txheej txheem npaj
Methylcellulose yog tsim los ntawm kev rov ua cellulose cellulose nrog methyl chloride (lossis methanol) nyob rau hauv alkaline tej yam kev mob. Thaum lub sij hawm tus txheej txheem no, ib feem ntawm cov pab pawg hydroxyl (-oh) hauv cov xov xwm cellules tau hloov los ntawm cov pab pawg methoxy (-ochiv) los ua methylcellulose. Cov degree ntawm kev hloov pauv (DS, tus naj npawb ntawm chav dej qab zib) ntawm methylcellulose txiav txim siab nws lub cev nqaij daim tawv thiab tshuaj lom neeg, xws li solubility thiab viscosity.
Carboxymetylcelleculose yog tsim los ntawm rapoloacetic acid nyob rau hauv alkaline cov xwm txheej, thiab cov pawg hydroxyl yog hloov los ntawm carboxymethyl (-ch₂cooh). Cov qib degree hloov chaw thiab qib ntawm polymerization (dp) cuam tshuam nws solubility thiab viscosity nyob rau hauv dej. CMC feem ntau muaj nyob rau hauv daim ntawv ntawm sodium ntsev, hu sodium carboxymethylcelleculose (nacmc).
2. Lub cev thiab tshuaj lom neeg
Solubility: methylcellulose nyob rau hauv dej txias, tab sis loses solubility thiab ua ib gel hauv dej kub. Qhov kev hloov hluav taws xob no ua rau nws siv los ua cov tuab tuab thiab tus neeg sawv cev hauv kev ua zaub mov noj. CMC yog soluble hauv ob qho tib si txias thiab dej kub, tab sis cov kev daws teeb meem tsawg dua li qhov kub nce ntxiv.
Viscosity: lub viscosity ntawm ob qho tib si cuam tshuam los ntawm qib kev hloov pauv thiab kev daws teeb meem. Lub viscosity ntawm MC Ua ntej nce thiab tom qab ntawd txo qis raws li qhov kub nce ntxiv, thaum lub viscosity ntawm cmc txo qis dua raws li qhov kub nce ntxiv. Qhov no muab lawv tus kheej zoo hauv cov ntawv thov sib txawv.
Pho stability: cmc tseem nyob ruaj khov ntau dua li cov kev mob dav, uas ua rau nws nrov heev li lub stabilizer thiab thickener hauv cov zaub mov thiab cov tshuaj. MC yog tus tsis ruaj khov nyob rau hauv nruab nrab thiab me ntsis alkaline tej yam kev mob, tab sis yuav ua phem rau hauv cov muaj zog acids lossis alkalis.
3. Cov chaw thov
Food industry: Methylcellulose is commonly used in food as a thickener, emulsifier and stabilizer. Piv txwv li, nws tuaj yeem ua piv txwv thiab kev ntxhib los mos ntawm cov rog thaum ua cov zaub mov muaj roj tsawg. Carboxymetylcellulose tau siv dav siv hauv cov dej haus thiab cov khoom noj noj haus ua cov ntaub tuab thiab stabilizer kom tiv thaiv kev sib cais dej thiab txhim kho cov dej sib cais.
Kws Tshuaj Kho Mob: Methylcellulose yog siv nyob rau hauv kev npaj cov ntsiav tshuaj ntawm cov ntsiav tshuaj ntawm cov tshuaj nplaum thiab tiv thaiv, xws li hauv ophthalmic qhov muag tee ua kua muag hloov. CMC tau siv dav hauv cov tshuaj vim nws qhov zoo biocompatibility, xws li kev npaj ntawm kev siv yeeb tshuaj uas muaj tshuaj lom neeg thiab cov nplaum hauv tee qhov muag.
Kev tsim kho thiab tshuaj kev lag luam: MC tau siv dav hauv cov ntaub ntawv hauv tsev ua cov tuab, dej khaws cia rau cov cement thiab Gypsum. Nws tuaj yeem txhim kho kev tsim kho kev tsim kho thiab cov khoom zoo ntawm cov ntaub ntawv. CMC feem ntau siv hauv kev paub hauv av hauv cov roj av Tsuas, slurry hauv textile luam ntawv thiab tawg ntawm daim ntawv, thiab lwm yam.
4. Kev Nyab Xeeb Kev Nyab Xeeb thiab Ib Puag Ncig
Ob qho tib si yog kev nyab xeeb rau kev siv hauv cov zaub mov thiab cov ntaub ntawv thov tshuaj, tab sis lawv cov txheej txheem thiab cov txheej txheem ntau lawm yuav muaj ntau qhov kev cuam tshuam rau ib puag ncig. Cov ntaub ntawv raw ntawm MC thiab CMC yog muab tau los ntawm cov ntaub ntawv ntuj ntuj thiab yog biodegradable, yog li lawv ua tau zoo nyob rau hauv cov nqe lus ntawm ib puag ncig kev phooj ywg. Txawm li cas los xij, lawv cov txheej txheem ntau lawm yuav cuam tshuam nrog cov kuab tshuaj lom neeg thiab cov tshuaj tiv thaiv, uas yuav muaj qee qhov cuam tshuam rau ib puag ncig.
5. Nqe thiab Kev Xav Tau
Vim muaj cov txheej txheem sib txawv ntau lawm, cov nqi ntau lawm ntawm methylcellulose feem ntau yog siab dua, yog li nws tus nqi lag luam kuj siab dua li carboxymellcellulose. CMC feem ntau muaj ntau dua kev lag luam xav tau vim nws cov nuj nqis dav thiab qis dua cov nqi ntau lawm.
Txawm hais tias methylcellulose thiab carboxymethylcelleculose yog ob qho tib si derivpose ntawm cov qauv, cov khoom, kev thov thiab kev thov lag luam. Methylcellulose feem ntau yog siv nyob rau hauv cov chaw noj mov, tshuaj thiab lub tsev cov ntaub ntawv vim nws qhov tshwj xeeb thermal reversibility thiab siab viscosity tswj. Carboxymethyl cellulose tau siv dav hauv cov zaub mov, tshuaj, textile thiab lwm yam kev lag luam vim tias kev hloov kho thiab dav pH kev hloov tau. Qhov kev xaiv ntawm cellulose derivative nyob ntawm daim ntawv thov kev tshwj xeeb thiab kev xav tau.
Lub Sijhawm Post: Lub Yim Hli 20-2024