Cellulose ether yog ib qho polymer hluavtaws ua los ntawm cov cellulose ntuj los ntawm kev hloov kho tshuaj. Cellulose ether yog ib qho derivative ntawm cellulose ntuj. Kev tsim cov cellulose ether txawv ntawm cov polymers hluavtaws. Nws cov khoom siv yooj yim tshaj plaws yog cellulose, ib qho tshuaj polymer ntuj. Vim yog qhov tshwj xeeb ntawm cov qauv cellulose ntuj, cellulose nws tus kheej tsis muaj peev xwm los cuam tshuam nrog cov neeg sawv cev etherification. Txawm li cas los xij, tom qab kev kho mob ntawm tus neeg sawv cev o, cov hydrogen bonds muaj zog ntawm cov saw hlau molecular thiab cov saw hlau raug rhuav tshem, thiab kev tso tawm ntawm pawg hydroxyl ua rau cov alkali cellulose reactive. Tau txais cellulose ether.
Cov khoom ntawm cellulose ethers nyob ntawm hom, tus lej thiab kev faib tawm ntawm cov substituents. Kev faib tawm ntawm cellulose ether kuj tseem raug faib raws li hom substituent, qib ntawm etherification, solubility thiab cov khoom siv cuam tshuam. Raws li hom substituents ntawm cov saw molecular, nws tuaj yeem faib ua monoether thiab sib xyaw ether. MC peb feem ntau siv yog monoether, thiab HPMC yog sib xyaw ether. Methyl cellulose ether MC yog cov khoom tom qab hydroxyl pawg ntawm chav glucose ntawm cellulose ntuj yog hloov los ntawm methoxy. Nws yog cov khoom tau los ntawm kev hloov ib feem ntawm hydroxyl pawg ntawm chav nrog ib pawg methoxy thiab lwm qhov nrog hydroxypropyl pawg. Cov qauv qauv yog [C6H7O2 (OH) 3-mn (OCH3) m [OCH2CH (OH) CH3] n] x Hydroxyethyl methyl cellulose ether HEMC, cov no yog cov ntau yam tseem ceeb siv dav thiab muag hauv khw.
Hais txog kev yaj, nws muaj peev xwm muab faib ua ionic thiab non-ionic. Cov dej-soluble non-ionic cellulose ethers feem ntau yog tsim los ntawm ob series ntawm alkyl ethers thiab hydroxyalkyl ethers. Ionic CMC feem ntau yog siv rau hauv cov tshuaj ntxuav hluavtaws, textile printing thiab dyeing, zaub mov thiab roj tshawb nrhiav. Non-ionic MC, HPMC, HEMC, thiab lwm yam feem ntau yog siv rau hauv cov ntaub ntawv siv hauv tsev, latex coatings, tshuaj, tshuaj txhua hnub, thiab lwm yam. Siv ua thickener, dej khaws cia tus neeg sawv cev, stabilizer, dispersant thiab zaj duab xis tsim tus neeg sawv cev.
Kev txheeb xyuas zoo ntawm cellulose ether:
Cov nyhuv ntawm cov ntsiab lus methoxyl rau qhov zoo: kev khaws dej thiab kev ua haujlwm tuab
Qhov cuam tshuam zoo ntawm cov ntsiab lus hydroxyethoxyl / hydroxypropoxyl: cov ntsiab lus siab dua, qhov zoo dua qhov khaws cia dej.
Kev cuam tshuam ntawm qhov zoo ntawm viscosity: qhov siab dua ntawm polymerization, qhov siab dua qhov viscosity thiab qhov zoo dua qhov khaws cia dej.
Qhov cuam tshuam ntawm qhov zoo ntawm qhov zoo: qhov zoo dua qhov kev tawg thiab kev yaj hauv cov mortar, qhov ceev dua thiab sib xws dua, thiab qhov khaws cia dej zoo dua
Qhov cuam tshuam zoo ntawm lub teeb transmittance: qhov siab dua qib ntawm polymerization, qhov sib xws ntau dua qib ntawm polymerization, thiab qhov tsawg dua impurities
Qhov cuam tshuam ntawm qhov kub thiab txias ntawm gel: qhov kub thiab txias ntawm gel rau kev tsim kho yog nyob ib puag ncig 75 ° C
Kev cuam tshuam ntawm qhov zoo ntawm dej: <5%, cellulose ether yooj yim nqus dej noo, yog li nws yuav tsum tau kaw thiab khaws cia
Qhov cuam tshuam zoo ntawm cov tshauv: <3%, qhov siab dua ntawm cov tshauv, qhov ntau ntawm cov khoom tsis huv
PH tus nqi zoo cuam tshuam: ze rau nruab nrab, cellulose ether muaj kev ua haujlwm ruaj khov ntawm PH: 2-11
Lub sijhawm tshaj tawm: Lub Ob Hlis-14-2023