Cellulose ether yog ib qho tseem ceeb tsim cov khoom siv ntxiv, siv cov hmoov av ua kom txhim kho lub zog thiab kev tsim kho cov khoom siv. Lub ntsiab Cheebtsam ntawm cellulose ether suav nrog cov qauv ntawm cellulose, uas muab nws tshwj xeeb solubility, thickening, dej khaws cia thiab rheological cov yam ntxwv.
1. Cellulose Cov Qauv Txheej Txheem
Cellulose yog ib qho ntawm feem ntau polysaccharides hauv qhov xwm, feem ntau yog muab los ntawm cov nroj tsuag fibers. Nws yog cov tseem ceeb tivthaiv ntawm cellulose ether thiab txiav txim nws cov qauv theem pib thiab khoom. Cellulose molecules yog tsim cov chav dej qab zib txuas nrog los ntawm β-1,4-glycosidic bonds los ua tus qauv ntev. Txoj kab no muab lub zog cellulose siab thiab qhov hnyav hnyav, tab sis nws solubility hauv dej yog neeg pluag. Txhawm rau txhim kho cov dej solubility ntawm cellulose thiab hloov kho rau cov kev xav tau ntawm cov ntaub ntawv hauv tsev, yuav tsum tau hloov cov tshuaj kho mob.
2. Txav tsis muaj qhov tseem ceeb ntawm kev tiv thaiv kab ntsig
Cov yam ntxwv tshwj xeeb ntawm cellulose ether yog ua tiav los ntawm cov neeg hloov chaw uas tau qhia los ntawm Ethegal pab pawg (-oh) ntawm cellulose thiab etheracter. Cov neeg hloov chaw nyob ib txwm muaj xws li mexoxy (-ochiv), kev sib zog ua ke (-oc₂h₅) thiab hydroxypropyl (-ch₂chopropyl). Cov lus qhia txog cov kev hloov pauv no hloov cov solubility, thickening thiab dej tuav ntawm cellulose. Raws li cov sib txawv qhia kev hloov chaw, cov kws ua cellulose tuaj yeem faib ua methulose (HEC), Hydroxypropyl cellulose (HPMC) thiab lwm hom.
Methyl Cellulose (MC): Methyl cellulose yog tsim los ntawm kev qhia methyl hloov (-ochiv pawg hauv cov pawg hydroxyl hauv lub cellulose molecule. Lub cellulose no ether muaj cov dej so kom zoo thiab thickening cov khoom thiab yog siv dav hauv cov tshuaj khib qhuav, cov nplaum thiab txheej. MC muaj cov dej txuag tau zoo heev hauv cov ntaub ntawv tsim hauv tsev, ua kom muaj cov nplaum thiab lub zog ntawm cov hmoov.
Hydroxyethyl cellulose (HEC): Hydroxyethyl cellulose yog tsim los ntawm kev qhia txog hydroxyethyl chaw (-oc₂h₅), uas ua rau nws muaj dej-soluble thiab ntsev-resistant. HEC feem ntau siv hauv cov dej pleev dej, cov xim yas thiab tsev ntxiv cov khoom ntxiv. Nws muaj qhov zoo heev thickening thiab zaj duab xis-ua cov khoom thiab tuaj yeem txhim kho kev tsim kho cov khoom siv.
HydroxyPropyyl Metylcellulose (HPMC): HydroxyPropylulose yog tsim los ntawm kev sib tham ntawm hydroxypropyl (-ch₂chohch₃) thiab methyl chaw. Hom cellulose ether cov dej zoo heev, lub cev ua haujlwm nyob hauv phab ntsa ua kom qhuav, thiab sab nrauv phab ntsa cov khoom qhwv phab ntsa. HPMC kuj muaj qhov kub ua hauj lwm zoo thiab khov ua kom tau zoo, yog li nws tuaj yeem txhim kho kev ua tau zoo ntawm cov ntaub ntawv hauv tsev nyob rau hauv huab cua huab cua.
3. Cov dej solubility thiab thickening
Cov dej ua kua ntawm cellulose ntawm cov pawg thiab qib hloov pauv ntawm txhua chav dej qab zib). Cov degree kom tsim nyog ntawm qhov chaw hloov cov molecules los ua ib qho kev daws teeb meem hauv dej, muab cov khoom siv zoo cov khoom siv. Hauv cov ntaub ntawv hauv tsev, cov neeg ua haujlwm cellulose raws li cov thickeners tuaj yeem nce cov viscosity ntawm cov khoom sib xyaw thiab sib cais ntawm cov ntaub ntawv, thiab txhim kho kev tsim kho kev tsim kho.
4. Dej Tuav
Cov dej tuav tseg ntawm cellulose ether yog qhov tseem ceeb heev rau cov khoom siv hauv tsev. Hauv cov khoom xws li tshuaj khib thiab ua kom muaj hmoov, cellulose ether tuaj yeem tsim cov khoom siv tsis ntev dhau los, yog li txuas tau lub sijhawm qhib thiab ua haujlwm ntawm cov khoom. Qhov no yog lub luag haujlwm tseem ceeb hauv kev txhim kho lub zog ua kom muaj zog thiab tiv thaiv kev tawg.
5. Rheology thiab Kev Siv Ua Haujlwm
Qhov kev sib ntxiv ntawm cov cellulose ether ho cuam tshuam ntau dua cov khoom siv hauv tsev, uas yog, kev coj txaus thiab deformation tus cwj pwm ntawm cov ntaub ntawv nyob rau hauv sab nraud rog. Nws tuaj yeem txhim kho cov dej khaws thiab lub cev ntawm cug, ua kom lub taub thiab yooj yim ntawm cov ntaub ntawv kev tsim kho. Hauv kev tsim kho xws li txau, scraping thiab masonry, cellulose, cellulose etheriency, thaum ua kom tiav cov txheej txheej tsis sib xws yam tsis muaj sagging.
6. Kev tiv thaiv thiab kev tiv thaiv ib puag ncig
Cellulose ether muaj kev sib raug zoo nrog ntau yam kev tsim kho, nws yuav tsis muaj kev cuam tshuam nrog lwm cov khoom siv tshuaj lom neeg kom ntseeg tau tias cov khoom muaj zog ntawm cov khoom. Tsis tas li ntawd, cellulose ether yog xim ntsuab ntxiv, uas yog feem ntau yog los ntawm cov nroj tsuag ntuj cog qoob loo, thiab ua kom muaj kev tiv thaiv ib puag ncig ib puag ncig, thiab muaj kev tiv thaiv ib puag ncig ntawm cov ntaub ntawv qub tsev.
7. Lwm cov khoom xyaw hloov pauv
Txhawm rau txhawm rau txhim kho kev ua haujlwm ntawm cellulose ether, lwm cov khoom xyaw hloov tshiab yuav raug qhia txog kev tsim khoom tiag tiag. Piv txwv li, qee cov tuam ntxhab yuav txhim kho cov dej tsis kam thiab huab cua tsis kam ntawm cellulose ethow los ntawm compounding nrog silicone, paraffin thiab lwm yam tshuaj. Qhov sib ntxiv ntawm cov khoom xyaw hloov no feem ntau yog ua kom tau raws li cov ntawv thov yuav tsum muaj, xws li nce cov khoom siv sab nrauv lossis cov khoom tsis muaj sia.
Raws li ib qho tseem ceeb hauv tsev, cellulose ether muaj ntau yam muaj zog, suav nrog cov dej ua kom tuab, thiab txhim kho cov khoom siv rheological. Nws lub ntsiab Cheebtsam yog lub cellulose cov qauv yooj yim thiab cov hloov chaw tuaj yeem qhia los ntawm Etherification cov tshuaj tiv thaiv. Ntau hom cellulose muaj cov neeg muaj cai sib txawv thiab ua yeeb yam hauv cov ntaub ntawv hauv tsev vim qhov sib txawv ntawm lawv cov chaw. Cov neeg muaj kev pab cuam cellulose tsis tuaj yeem txhim kho kev ua haujlwm ntawm cov ntaub ntawv, tab sis tseem txhim kho kom muaj kev ua tau zoo thiab kev pabcuam lub neej tag nrho. Yog li ntawd, cellulose muaj kev hais kom muaj kev cuam tshuam thov cov kev cia siab hauv cov khoom siv niaj hnub no.
Lub Sijhawm Post: Sep-18-2024