1. Lub ntsiab tseem ceeb ntawm cellulose ether
Hauv kev npaj-sib nphu cellulose ether yog ib qho kev ua tau zoo ntawm cov tshuaj khib nyiab uas tsis muaj zog thiab cuam tshuam rau kev ua haujlwm ntawm cug.
2. Hom ntawm cov cellulose muaj kev hais ua
Kev tsim cov cellulose ether yog feem ntau yog ua los ntawm ntuj fibers los ntawm alkali dissolution, kev sib tsoo), ntxuav) thiab lwm yam kev ua tiav.
Raws li cov ntaub ntawv raw tseem ceeb, cov khoom noj ntuj tuaj yeem faib ua: RAJ Fiber, CEDAR Fiber, muaj cov qib ntawm polymerization sib txawv, uas cuam tshuam rau qhov kawg viscosity ntawm lawv cov khoom. Tam sim no, cellulose cellulose tuam tsev siv cov paj rwb fiber ntau (los ntawm nitrocellulose) raws li cov khoom siv tseem ceeb.
Cellulose muaj kev hais ua neeg tuaj yeem muab faib ua ionic thiab noonicic. Lub ionic hom tsuas yog suav nrog carboxymethyl cellulose cellulose cell, thiab hom tsis yog tshuaj ntsuab, methyl hydrothethyl (hydroxyethyl cellulose, thiab lwm yam.
Nyob rau tam sim no, lub cellulose muaj kev pab cuam uas npaj txhij txhua cellulose cellulose cellulose cellulropyl cellulope cellulose ether (HPMC). Hauv kev npaj tshuaj khib nyiab, vim ionic cellulose (carboxymethyl cellulose cellulose cellulose uas siv cov cement, thiab lwm yam raws li cov ntaub ntawv tsoosting. Hauv qee qhov chaw hauv Suav teb, Carboxymethyl cellulose cellulose nrog cov khoom siv ua tiav raws li cov khoom siv khov kho thiab shuangdei hmoov zoo li tus muab tub lim. Cov khoom lag luam no yog tus nquag ua rau cov neeg tsis txaus siab thiab tsis kam tiv taus dej, thiab tam sim no yog cov phased tawm. Hydroxyethyl cellulose kuj siv nyob rau hauv qee cov khoom txhij-sib xyaw, tab sis muaj cov lag luam sib txuas me me.
3. Cov ntsiab lus tseem ceeb ntawm cellulose ether
(1) solubility
Cellulose yog polyhydroxy polymer compound uas tsis yaj tag nrho tsis yaj. Tom qab ethermalation, cellulose yog soluble hauv dej, dilute alkali daws thiab organic kuab tshuaj, thiab muaj thermoplasticity. Solubility tsuas yog nyob ntawm plaub yam: thawj zaug, solubility sib txawv nrog viscosity, qhov qis dua viscosity, muaj ntau dua cov solubility. Thib ob, cov yam ntxwv ntawm cov pab pawg qhia nyob rau hauv etherification txheej txheem, cov loj dua pawg tau qhia, qis dua cov solubility; Qhov ntau ntawm pawg tau qhia, qhov yooj yim lub cellulose ether yog kom yaj hauv dej. Thib peb, qib degree hloov chaw thiab kev faib tawm ntawm Eletherified pawg hauv Macromolecules. Feem ntau cov kws kho mob cellulose tsuas yog ua kom yaj hauv dej nyob rau hauv ib qho degree ntawm kev hloov pauv. Plaub, qib ntawm polymerization ntawm cellulose ether, nce qib siab ntawm polymerization, qhov tsawg dua soluble; Qhov qis dua qib ntawm polymerization, qhov dav ntau ntawm cov qib ntawm kev hloov chaw uas tuaj yeem yaj hauv dej.
(2) cov dej ua haujlwm
Dej khaws cia yog ib qho kev ua tau tseem ceeb ntawm cellulose ether, thiab nws yog cov neeg tsim hmoov nplej uas muaj ntau yam kub thiab txias, xyuam xim rau. Yam cuam tshuam rau cov dej khaws cov tshuaj khib muaj xws li tus nqi ntawm cellulose eether ntxiv, viscosity zoo heev thiab ntsuas kub ntawm kev siv ib puag ncig. Qhov siab dua tus nqi ntawm cov cellulose ether ntxiv, qhov zoo dua cov dej ua kom ruaj khov; Qhov ntau dua qhov viscosity, qhov zoo dua cov dej tswj kav dej ruaj khov; Cov khoom ua kom tiav cov khoom, qhov zoo dua cov dej ua kom ruaj khov.
(3) viscosity
Viscosity yog ib qho tseem ceeb ntsuas ntawm cov khoom siv ether ether. Tam sim no, kev sib txawv cellulose etherers siv cov qauv sib txawv thiab cov cuab yeej ntsuas qhov viscosity. Rau tib cov khoom lag luam, cov viscosity tau ntsuas los ntawm cov qauv sib txawv yog qhov sib txawv heev, thiab qee tus txawm tau muaj ob npaug sib txawv. Yog li ntawd, thaum piv cov viscosity, nws yuav tsum tau nqa tawm ntawm tib txoj kev ntsuas, suav nrog qhov kub thiab lwm yam.
Feem ntau hais lus, ntau dua cov viscosity, qhov zoo dua cov dej khaws cov nyhuv khaws cia. Txawm li cas los xij, qhov siab tshaj plaws viscosity, ntau dua cov molecular hnyav ntawm cellulose cuam tshuam rau hauv nws cov solubility, thiab cov tshuaj tsis zoo rau lub zog thiab kev tsim kho ntawm lub tshuaj khib. Qhov siab tshaj lub viscosity, qhov pom ntau ntxiv rau cov nyhuv tuab rau ntawm lub tshuaj khib, tab sis nws tsis ncaj ncaj ncaj. Qhov siab tshaj lub viscosity, ntau ntau ntau lub volt ntub lub cug yuav. Thaum kev tsim kho, nws yog manifested raws li sticking rau tus scraper thiab siab adhesion rau lub substrate. Tab sis nws tsis muaj txiaj ntsig zoo rau kev nce cov txheej txheem lub zog ntawm lub txiv ntoo qhuav nws tus kheej. Thaum kev tsim kho, kev ua haujlwm tsis zoo yog tsis pom tseeb. Ntawm qhov tsis sib xws, qee qhov nruab nrab thiab qis viscosity tab sis hloov kho metyl cellulose cellulose kev ua tau zoo tshaj plaws hauv kev txhim kho lub zog ntawm cov tshuaj khib nyiab ntub dej.
(4) Cov ntsiab lus zoo ntawm cov khoom:
Lub cellulose ether tau siv rau npaj-sib tov tov, nrog cov ntsiab lus dej sib xyaw, thiab cov ntsiab lus qis yuav tsum muaj 20% rau 60% ntawm cov particle loj kom tsawg dua 63 μm. Cov txiaj ntsig cuam tshuam rau cov solubility ntawm cellulose ether. Cov neeg txawj ntse cellulose feem ntau yog nyob rau hauv daim ntawv ntawm granules, uas yog qhov yooj yim rau kev siv dej sib tov (qee cov khoom siv hauv tsev yog flocculent, Tsis yooj yim rau disperse thiab yaj hauv dej, thiab nquag ua kom zoo nkauj). Hauv kev npaj-sib nphu cellulose ether yog tawg ntawm aggregates, nplua fitters thiab cementing thiab lwm yam khoom noj xis. Tsuas yog cov hmoov zoo txaus xwb tuaj yeem zam kev cellulose ether agglomeration thaum sib xyaw nrog dej. Thaum cellulose ether yog ntxiv nrog dej kom yaj lub agglomeration, nws yog qhov nyuaj rau kev ntiab tawm thiab yaj.
(5) kev hloov kho ntawm cellulose ether
Kev hloov kho ntawm cellulose ether yog qhov txuas ntxiv ntawm nws cov kev ua tau zoo, thiab nws yog qhov tseem ceeb tshaj plaws. Cov yam ntxwv ntawm cellulose ether tuaj yeem txhim kho nws cov wettity, thickening, ua kom muaj zog, emulsing, fluctening, ua yeeb yam zoo li nws impermility rau roj.
4. Cov nyhuv ntawm qhov kub cua sov ntawm dej ceev ntawm cug
Cov dej khaws cia ntawm cellulose ether tsawg txo nrog qhov nce ntawm kub. Hauv cov ntawv thov tswv yim, tshuaj khib feem ntau yog siv rau kub substrates ntawm qhov kub (siab dua 40 ° C) nyob rau hauv ntau cov chaw. Qhov poob hauv dej khaws cia kom muaj kev cuam tshuam rau kev ua haujlwm ntawm kev ua haujlwm thiab tawg. Nws txoj kev vam khom rau qhov kub thiab txias tseem yuav ua rau muaj zog ntawm cov tshuaj khib, thiab nws yog qhov tshwj xeeb tshaj yog txo tus mob kub. Tshuaj khib cov lus qhia raug muab kho kom haum, thiab ntau yam kev hloov tseem ceeb tau ua hauv cov zaub mov txawv caij nyoog. Txawm hais tias nce cov koob tshuaj tivteeb (lub caij ntuj sov lub cev), kev ua haujlwm tsis tuaj yeem ua tau kev kho mob etherification, thiab lwm yam kom cov dej khaws cia ua tiav ntawm cov kub siab. Nws tau ua kom muaj kev cuam tshuam zoo dua thaum nws yog qhov siab, yog li nws muab kev ua tau zoo dua hauv kev mob hnyav.
5. Daim ntawv thov nyob rau hauv npaj-mixeded cug
Hauv kev npaj-sib nphu cellulose enhether ua lub luag haujlwm ntawm dej khaws cia, thickening thiab txhim kho kev tsim kho kev ua haujlwm. Cov dej zoo khaws cia ua tau zoo tias lub tshuaj khib yuav tsis ua rau sanding, hmoov thiab kev daws teeb meem thiab kev tsis txaus siab. Cov nyhuv thickening heev ua tau zoo dua rau lub zog ntawm lub zog ntawm lub cug cug ntub. Qhov kev sib txuas lus ntawm cellulose ether tuaj yeem txhim kho viscosity ntub, yog li txhim kho phab ntsa ntub thiab txo cov khib nyiab thiab txo cov pov tseg. Ib qho ntxiv, lub luag haujlwm ntawm cellulose ether hauv cov khoom sib txawv kuj txawv. Piv txwv li, hauv cov nplais nplaum, cellulose ether tuaj yeem ua rau lub sijhawm qhib thiab kho lub sijhawm; Hauv cov tshuab tshuaj txau cug, nws tuaj yeem txhim kho lub zog ntawm cov tshuaj khib ntub; Hauv kev coj tus kheej, nws tuaj yeem tiv thaiv kev sib hais haum, cais thiab stratification. Yog li ntawd, raws li qhov tseem ceeb ntxiv, cellulose ether yog dav siv nyob rau hauv cov hmoov av qhuav.
Lub Sijhawm Post: Jan-11-2023