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 ethers kuj yog raws li hom substituents, 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. Peb feem ntau siv mc ua monoether, thiab HPmc ua 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 pawg. Nws yog cov khoom tau los ntawm kev hloov ib feem ntawm hydroxyl pawg ntawm chav nrog methoxy pawg 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.
Lub sijhawm tshaj tawm: Kaum Ib Hlis-24-2022