Cov cellulose ethers yog cov tshuaj siv tau ntau yam hauv ntau yam lag luam suav nrog kev tsim kho, tshuaj thiab khoom noj. Cov txheej txheem tsim cov cellulose ether yog qhov nyuaj heev, muaj ntau kauj ruam, thiab xav tau ntau yam kev txawj ntse thiab cov khoom siv tshwj xeeb. Hauv tsab xov xwm no, peb yuav tham txog cov txheej txheem tsim cov cellulose ethers.
Kauj ruam thawj zaug hauv cov txheej txheem tsim cov cellulose ether yog kev npaj cov khoom siv raw. Cov khoom siv raw siv los tsim cov cellulose ethers feem ntau yog los ntawm cov ntoo pulp thiab cov paj rwb pov tseg. Cov ntoo pulp raug txiav thiab tshuaj ntsuam kom tshem tawm cov khib nyiab loj, thaum cov paj rwb pov tseg raug ua tiav rau hauv cov pulp zoo. Cov pulp tom qab ntawd raug txo qhov loj me los ntawm kev sib tsoo kom tau txais cov hmoov zoo. Cov ntoo pulp hmoov thiab cov paj rwb pov tseg tom qab ntawd raug sib xyaw ua ke hauv cov feem tshwj xeeb nyob ntawm cov yam ntxwv xav tau ntawm cov khoom kawg.
Kauj ruam tom ntej no yog kev ua cov khoom noj sib xyaw ua ke. Ua ntej, cov pulp raug kho nrog cov kua alkaline (feem ntau yog sodium hydroxide) kom rhuav tshem cov qauv fibrous ntawm cellulose. Tom qab ntawd, cov cellulose uas tau los raug kho nrog cov kuab tshuaj xws li carbon disulfide los tsim cov cellulose xanthate. Kev kho no yog ua tiav hauv cov thoob dej uas muaj cov pulp tas li. Cov kua cellulose xanthate ces raug extruded los ntawm lub cuab yeej extrusion los ua cov filaments.
Tom qab ntawd, cov cellulose xanthate filaments tau raug tig hauv lub dab dej uas muaj dilute sulfuric acid. Qhov no ua rau muaj kev rov tsim dua ntawm cov saw hlau cellulose xanthate, tsim cov cellulose fibers. Cov cellulose fibers tshiab tsim tom qab ntawd raug ntxuav nrog dej kom tshem tawm cov khoom tsis huv ua ntej raug bleached. Cov txheej txheem bleaching siv hydrogen peroxide los ua kom cov cellulose fibers dawb, uas tom qab ntawd raug ntxuav nrog dej thiab cia kom qhuav.
Tom qab cov cellulose fibers qhuav lawm, lawv dhau los ntawm cov txheej txheem hu ua etherification. Cov txheej txheem etherification cuam tshuam nrog kev qhia txog cov pab pawg ether, xws li methyl, ethyl lossis hydroxyethyl pawg, rau hauv cov cellulose fibers. Txoj kev no yog ua tiav los ntawm kev siv cov tshuaj tiv thaiv ntawm tus neeg sawv cev etherification thiab cov tshuaj tua kab mob acid nyob rau hauv qhov muaj cov kuab tshuaj. Cov tshuaj tiv thaiv feem ntau yog ua tiav nyob rau hauv kev tswj hwm zoo ntawm qhov kub thiab txias kom ntseeg tau tias cov khoom lag luam siab thiab huv si.
Lub sijhawm no, cov cellulose ether yog nyob rau hauv daim ntawv ntawm cov hmoov dawb. Cov khoom tiav lawm ces raug rau ntau qhov kev sim tswj kom ntseeg tau tias cov khoom ua tau raws li qhov xav tau thiab cov lus qhia, xws li viscosity, cov khoom purity thiab cov dej noo. Tom qab ntawd nws raug ntim thiab xa mus rau tus neeg siv kawg.
Hauv kev xaus lus, cov txheej txheem tsim cov cellulose ether suav nrog kev npaj cov khoom siv raw, kev kho tshuaj, kev sib hloov, kev ua kom dawb thiab kev sib xyaw ua ke, ua raws li kev sim tswj xyuas zoo. Tag nrho cov txheej txheem xav tau cov khoom siv tshwj xeeb thiab kev paub txog cov tshuaj lom neeg thiab ua tiav raws li cov xwm txheej tswj hwm nruj. Kev tsim cov cellulose ethers yog ib qho txheej txheem nyuaj thiab siv sijhawm ntau, tab sis nws tseem ceeb heev hauv ntau yam lag luam.
Lub sijhawm tshaj tawm: Lub Rau Hli-21-2023