CMC feem ntau yog anionic polymer compound npaj los ntawm reacting natural cellulose nrog caustic alkali thiab monochloroacetic acid, nrog ib tug molecular hnyav ntawm 6400 (± 1 000). Cov khoom lag luam tseem ceeb yog sodium chloride thiab sodium glycolate. CMC belongs rau natural cellulose hloov. Nws tau raug hu ua "hloov cellulose" los ntawm Food and Agriculture Organization of United Nations (FAO) thiab World Health Organization (WHO).
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Cov cim tseem ceeb los ntsuas qhov zoo ntawm CMC yog qhov kev hloov pauv (DS) thiab purity. Feem ntau, cov khoom ntawm CMC txawv thaum DS txawv; qhov siab dua qhov kev hloov pauv, qhov zoo dua qhov solubility, thiab qhov zoo dua qhov pom thiab ruaj khov ntawm cov tshuaj. Raws li cov lus ceeb toom, lub pob tshab ntawm CMC yog qhov zoo dua thaum qhov kev hloov pauv yog 0.7-1.2, thiab viscosity ntawm nws cov kua dej yog qhov loj tshaj plaws thaum pH tus nqi yog 6-9. Txhawm rau kom ntseeg tau nws qhov zoo, ntxiv rau kev xaiv tus neeg sawv cev etherifying, qee yam uas cuam tshuam rau qib kev hloov pauv thiab purity yuav tsum tau txiav txim siab, xws li kev sib raug zoo ntawm alkali thiab etherifying tus neeg sawv cev, lub sijhawm etherification, cov ntsiab lus dej, qhov kub thiab txias. , pH tus nqi, kua concentration thiab ntsev.
Kev tshuaj xyuas qhov zoo thiab qhov tsis zoo ntawm sodium carboxymethyl cellulose
Kev loj hlob ntawm sodium carboxymethyl cellulose yog qhov tseeb tsis tau muaj dua. Tshwj xeeb tshaj yog nyob rau hauv xyoo tas los no, kev nthuav dav ntawm daim ntawv thov teb thiab txo cov nqi tsim khoom tau ua rau kev tsim cov carboxymethyl cellulose ntau thiab nrov dua. Cov khoom ntawm kev muag khoom yog sib xyaw.
Tom qab ntawd, yuav ua li cas txiav txim siab qhov zoo ntawm sodium carboxymethyl cellulose, peb txheeb xyuas los ntawm qee qhov kev xav ntawm lub cev thiab tshuaj:
Ua ntej tshaj plaws, nws tuaj yeem paub qhov txawv ntawm nws qhov kub thiab txias carbonization. Qhov dav dav carbonization kub ntawm sodium carboxymethyl cellulose yog 280-300 ° C. Thaum nws yog carbonized ua ntej qhov kub ntawm no mus txog, ces cov khoom no muaj teeb meem. (Feem ntau carbonization siv muffle furnace)
Qhov thib ob, nws yog qhov txawv ntawm nws qhov kub thiab txias. Feem ntau, sodium carboxymethyl cellulose yuav hloov xim thaum nws ncav cuag qhov kub thiab txias. Qhov ntsuas kub yog 190-200 ° C.
Thirdly, nws tuaj yeem txheeb xyuas los ntawm nws qhov tsos. Cov tsos ntawm cov khoom feem ntau yog cov hmoov dawb, thiab nws qhov loj me yog feem ntau 100 mesh, thiab qhov tshwm sim ntawm kev hla dhau yog 98.5%.
Sodium carboxymethyl cellulose yog cov khoom siv cellulose siv dav heev thiab muaj ntau yam kev siv, yog li tej zaum yuav muaj qee qhov kev coj ua hauv khw. Yog li yuav ua li cas txheeb xyuas seb nws puas yog cov khoom xav tau los ntawm cov neeg siv tuaj yeem xeem dhau qhov kev kuaj xyuas tus lej hauv qab no.
Xaiv 0.5g ntawm sodium carboxymethyl cellulose, uas tsis paub meej tias nws yog cov khoom ntawm sodium carboxymethylcellulose, yaj nws hauv 50mL dej thiab do, ntxiv me me txhua zaus, do ntawm 60 ~ 70 ℃, thiab cua sov rau 20 feeb. ua ib qho kev daws teeb meem, txias Tom qab kuaj xyuas cov kua, cov kev sim hauv qab no tau ua tiav.
1. Ntxiv dej rau qhov kev sim tshuaj kom dilute 5 zaug, ntxiv 0.5mL ntawm chromotropic acid test tov rau 1 tee ntawm nws, thiab muab tso rau hauv dej da dej rau 10 feeb kom pom liab-liab.
2. Ntxiv 10 mL ntawm acetone rau 5 mL ntawm cov tshuaj ntsuam xyuas, co thiab sib tov kom huv si los tsim ib tug dawb flocculent precipitate.
3. Ntxiv 1mL ntawm ketone sulfate test tov rau 5mL ntawm kev sim tshuaj, sib tov thiab co kom tsim lub teeb xiav flocculent precipitate.
4. Cov residue tau los ntawm ashing ntawm cov khoom no qhia cov pa tshuaj tiv thaiv ntawm sodium ntsev, uas yog, sodium carboxymethyl cellulose.
Los ntawm cov kauj ruam no, koj tuaj yeem txheeb xyuas seb cov khoom yuav khoom puas yog sodium carboxymethyl cellulose thiab nws cov purity, uas muab txoj hauv kev yooj yim thiab siv tau rau cov neeg siv khoom kom raug xaiv cov khoom.
Lub sij hawm xa tuaj: Nov-12-2022