Kev tsim cov carboxymethylcellulose (CMC) muaj ob peb kauj ruam thiab cov tshuaj tiv thaiv.CMC yog cov dej-soluble polymer muab tau los ntawm cellulose, ib tug natural polymer pom nyob rau hauv lub cell phab ntsa ntawm cov nroj tsuag.Nws yog dav siv nyob rau hauv ntau yam lag luam xws li zaub mov, tshuaj, tshuaj pleev ib ce, thiab textiles vim nws thickening, stabilizing, thiab binding zog.Nov yog cov lus qhia ntxaws ntxaws txog yuav ua li cas tsim carboxymethylcellulose:
Taw qhia rau Carboxymethylcellulose (CMC):
Carboxymethylcellulose (CMC) yog ib tug derivative ntawm cellulose, ib txwm tshwm sim polysaccharide pom nyob rau hauv cov nroj tsuag cell phab ntsa.Kev tsim khoom ntawm CMC suav nrog kev hloov kho cellulose los ntawm cov tshuaj tiv thaiv kab mob los qhia cov pawg carboxymethyl mus rau cov pob txha cellulose.Qhov kev hloov kho no muab cov dej solubility thiab lwm yam khoom tsim nyog rau cov polymer.
Raw Khoom:
Cellulose: Lub ntsiab raw khoom rau CMC ntau lawm yog cellulose.Cellulose tuaj yeem tau txais los ntawm ntau yam ntuj tsim xws li ntoo pulp, paj rwb linters, lossis cov khoom ua liaj ua teb.
Sodium Hydroxide (NaOH): Kuj hu ua caustic soda, sodium hydroxide yog siv nyob rau hauv thawj theem ntawm CMC zus tau tej cov cellulose alkali kev kho mob.
Chloroacetic Acid (ClCH2COOH): Chloroacetic acid yog lub ntsiab reagent siv los qhia carboxymethyl pawg mus rau hauv cov pob txha cellulose.
Etherification Catalyst: Cov catalysts xws li sodium hydroxide lossis sodium carbonate yog siv los pab txhawb cov tshuaj tiv thaiv etherification ntawm cellulose thiab chloroacetic acid.
Cov kuab tshuaj: Cov kuab tshuaj xws li isopropanol lossis ethanol tuaj yeem siv los ua kom yaj cov reactants thiab pab hauv cov txheej txheem tshuaj tiv thaiv.
Txheej txheem ntau lawm:
Kev tsim cov carboxymethylcellulose muaj ob peb kauj ruam tseem ceeb:
1. Kev kho Alkali ntawm Cellulose:
Cellulose yog kho nrog ib tug muaj zog alkali, feem ntau sodium hydroxide (NaOH), kom nws reactivity los ntawm converting ib co ntawm nws cov hydroxyl pawg rau alkali cellulose.Qhov kev kho no feem ntau yog nqa tawm hauv lub nkoj reactor ntawm qhov kub siab.Cov alkali cellulose tsim yog ces ntxuav thiab neutralized kom tshem tawm ntau tshaj alkali.
2. Etherification:
Tom qab kev kho alkali, cellulose yog reacted nrog chloroacetic acid (ClCH2COOH) nyob rau hauv lub xub ntiag ntawm ib tug etherification catalyst.Cov tshuaj tiv thaiv no qhia txog cov pab pawg carboxymethyl mus rau cov pob txha cellulose, uas ua rau tsim cov carboxymethylcellulose.Cov tshuaj tiv thaiv etherification feem ntau tshwm sim nyob rau hauv kev tswj xyuas qhov kub thiab txias, siab, thiab pH kom ua tiav qhov kev xav tau ntawm kev hloov pauv (DS) thiab molecular hnyav ntawm CMC.
3. Ntxuav thiab Purification:
Ua raws li cov tshuaj tiv thaiv etherification, cov khoom siv raw CMC raug ntxuav kom huv si kom tshem tawm cov tshuaj tsis muaj tshuaj, cov khoom lag luam, thiab cov khoom tsis huv.Kev ntxuav feem ntau yog siv dej los yog cov kuab tshuaj organic ua raws li kev pom los yog centrifugation.Cov kauj ruam ua kom huv kuj tseem yuav cuam tshuam nrog kev kho mob nrog cov kua qaub lossis cov hauv paus los kho pH thiab tshem tawm cov catalysts seem.
4. Qhuav:
CMC purified ces qhuav kom tshem tawm cov dej noo thiab tau txais cov khoom kawg hauv cov hmoov los yog granular daim ntawv.Kev ziab yog feem ntau yog ua los ntawm kev siv cov txheej txheem xws li tshuaj tsuag kom qhuav, lub tshuab nqus tsev kom qhuav, lossis ziab cua hauv kev tswj xyuas kom tsis txhob degradation lossis agglomeration ntawm cov polymer.
Kev Tswj Xyuas Zoo:
Kev tswj xyuas kev ua tau zoo yog qhov tseem ceeb thoob plaws hauv CMC cov txheej txheem tsim khoom kom ntseeg tau qhov sib xws, purity, thiab cov khoom xav tau ntawm cov khoom kawg.Cov yam ntxwv tseem ceeb muaj xws li:
Degree ntawm kev hloov pauv (DS): Qhov nruab nrab ntawm cov carboxymethyl pawg ib chav tsev piam thaj hauv cov saw cellulose.
Molecular hnyav tis: txiav txim los ntawm cov tswv yim xws li viscosity ntsuas los yog gel permeation chromatography (GPC).
Purity: Ntsuas los ntawm kev tshuaj ntsuam xyuas xws li infrared spectroscopy (IR) lossis ua kua chromatography (HPLC) kom pom cov impurities.
Viscosity: Cov cuab yeej tseem ceeb rau ntau daim ntawv thov, ntsuas siv viscometers kom ntseeg tau tias muaj kev sib luag thiab kev ua haujlwm.
Daim ntawv thov ntawm Carboxymethylcellulose:
Carboxymethylcellulose pom kev siv dav hauv ntau lub lag luam, suav nrog:
Kev lag luam khoom noj khoom haus: Raws li lub thickener, stabilizer, thiab emulsifier nyob rau hauv cov khoom xws li kua ntses, hnav khaub ncaws, ice cream, thiab ci khoom.
Pharmaceuticals: Nyob rau hauv cov tshuaj formulations raws li ib tug binder, disintegrant, thiab viscosity modifier nyob rau hauv cov ntsiav tshuaj, suspensions, thiab tshuaj pleev formulations.
Tshuaj pleev ib ce: Nyob rau hauv cov khoom tu tus kheej xws li cream, tshuaj pleev ib ce, thiab tshuaj zawv plaub hau raws li ib tug thickening neeg sawv cev thiab rheology modifier.
Textiles: Nyob rau hauv textile printing, sizing, thiab finishing txheej txheem los txhim kho ntaub zog thiab kev ua tau zoo.
Environmental thiab Safety Considerations:
Kev tsim khoom CMC suav nrog kev siv tshuaj thiab cov txheej txheem siv hluav taws xob, uas yuav muaj kev cuam tshuam ib puag ncig xws li kev tsim dej khib nyiab thiab kev siv hluav taws xob.Kev siv zog los txo qhov cuam tshuam ib puag ncig thiab ua kom muaj kev nyab xeeb ntawm cov tshuaj yog qhov tseem ceeb hauv CMC kev tsim khoom.Kev siv cov kev coj ua zoo tshaj plaws rau kev kho cov khib nyiab, kev siv hluav taws xob, thiab kev noj qab haus huv thiab kev nyab xeeb tuaj yeem pab txo cov kev txhawj xeeb no.
Kev tsim cov carboxymethylcellulose suav nrog ob peb kauj ruam pib los ntawm kev rho tawm cellulose mus rau kev kho alkali, etherification, purification, thiab ziab.Kev tswj xyuas kev ua tau zoo yog qhov tseem ceeb los xyuas kom meej qhov sib xws thiab purity ntawm cov khoom kawg, uas pom cov ntawv thov dav thoob plaws ntau qhov kev lag luam.Kev txiav txim siab ib puag ncig thiab kev nyab xeeb yog qhov tseem ceeb ntawm CMC kev tsim khoom, hais txog qhov xav tau rau kev tsim khoom lag luam ruaj khov thiab muaj lub luag haujlwm.
Post lub sij hawm: Mar-27-2024