Siv cellulose ua raw khoom,CMC-Natau npaj los ntawm txoj kev ob-kauj ruam. Thawj yog cov txheej txheem alkalization ntawm cellulose. Cov cellulose reacts nrog sodium hydroxide los tsim alkali cellulose, thiab tom qab ntawd cov alkali cellulose reacts nrog chloroacetic acid los tsim CMC-Na, uas yog hu ua etherification.
Cov tshuaj tiv thaiv kab mob yuav tsum yog alkaline. Cov txheej txheem no belongs rau Williamson ether synthesis method. Cov tshuaj tiv thaiv mechanism yog nucleophilic hloov pauv. Cov tshuaj tiv thaiv kab mob yog alkaline, thiab nws tau nrog qee qhov kev cuam tshuam sab hauv cov dej, xws li sodium glycolate, glycolic acid thiab lwm yam khoom lag luam. Vim muaj qhov tshwm sim ntawm sab, kev noj cov alkali thiab etherification tus neeg sawv cev yuav nce, yog li txo cov etherification efficiency; Ib txhij, sodium glycolate, glycolic acid thiab ntau ntsev impurities tuaj yeem tsim nyob rau hauv cov tshuaj tiv thaiv sab, ua rau purity thiab kev ua tau zoo ntawm cov khoom. Txhawm rau txhawm rau tiv thaiv sab nraud, nws yog ib qho tsim nyog tsis yog tsuas yog siv alkali tsim nyog, tab sis kuj tswj cov dej system, qhov concentration ntawm alkali thiab stirring txoj kev rau lub hom phiaj ntawm txaus alkalization. Nyob rau tib lub sijhawm, qhov yuav tsum tau ua ntawm cov khoom ntawm viscosity thiab degree ntawm kev hloov pauv yuav tsum raug txiav txim siab, thiab qhov sib tov ceev thiab kub yuav tsum raug txiav txim siab. Tswj thiab lwm yam, nce tus nqi ntawm etherification, thiab inhibit qhov tshwm sim ntawm sab tshwm sim.
Raws li cov xov xwm etherification sib txawv, kev tsim khoom ntawm CMC-Na tuaj yeem muab faib ua ob pawg: dej-raws li txoj kev thiab cov txheej txheem hnyav. Txoj kev siv dej raws li qhov nruab nrab cov tshuaj tiv thaiv yog hu ua dej nruab nrab txoj kev, uas yog siv los tsim alkaline nruab nrab thiab qis-qib CMC-Na. Cov txheej txheem ntawm kev siv cov kuab tshuaj organic raws li qhov nruab nrab cov tshuaj tiv thaiv yog hu ua cov txheej txheem hnyav, uas yog tsim rau kev tsim cov khoom nruab nrab thiab qib siab CMC-Na. Ob qhov kev cuam tshuam no tau ua tiav hauv lub tshuab kneader, uas yog cov txheej txheem kneading thiab tam sim no yog txoj hauv kev tseem ceeb rau kev tsim CMC-Na.
Dej nruab nrab txoj kev:
Cov txheej txheem dej-dej yog txheej txheem kev lag luam ua ntej, uas yog los ua cov tshuaj alkali cellulose thiab etherification tus neeg sawv cev nyob rau hauv cov xwm txheej ntawm dawb alkali thiab dej. Thaum lub sij hawm alkalization thiab etherification, tsis muaj cov organic nruab nrab hauv lub cev. Cov cuab yeej siv ntawm cov txheej txheem dej tawm yog qhov yooj yim, nrog kev nqis peev tsawg thiab tus nqi qis. Qhov tsis zoo yog qhov tsis muaj qhov loj ntawm cov kua nruab nrab, cov cua sov tsim los ntawm cov tshuaj tiv thaiv ua rau kom qhov kub thiab txias, ua kom nrawm nrawm ntawm cov tshuaj tiv thaiv sab, ua rau tsis muaj etherification efficiency, thiab cov khoom tsis zoo. Cov txheej txheem yog siv los npaj cov khoom nruab nrab thiab qib qis CMC-Na, xws li cov tshuaj detergents, textile sizing agents thiab lwm yam.
Solvent method:
Cov txheej txheem hnyav kuj tseem hu ua cov txheej txheem organic hnyav, thiab nws lub ntsiab tseem ceeb yog tias cov tshuaj alkalization thiab etherification tshwm sim nyob rau hauv cov xwm txheej ntawm cov organic hnyav raws li cov tshuaj tiv thaiv nruab nrab (diluent). Raws li tus nqi ntawm reactive diluent, nws muab faib ua kneading txoj kev thiab slurry txoj kev. Cov txheej txheem hnyav yog tib yam li cov txheej txheem ntawm cov txheej txheem dej, thiab tseem muaj ob theem ntawm alkalization thiab etherification, tab sis cov tshuaj tiv thaiv nruab nrab ntawm ob theem no txawv. Cov txheej txheem hnyav txuag cov txheej txheem ntawm soaking alkali, nias, crushing, aging thiab thiaj li nyob rau hauv lub hauv paus ntawm cov dej txoj kev, thiab cov alkalization thiab etherification yog tag nrho cov nqa tawm nyob rau hauv lub kneader. Qhov tsis zoo yog tias qhov ntsuas kub tswj tau qhov tsis zoo, thiab qhov chaw yuav tsum tau muaj thiab tus nqi siab. Tau kawg, rau kev tsim cov khoom siv sib txawv, nws yog ib qho tsim nyog yuav tsum nruj me ntsis tswj lub cev kub, lub sij hawm pub mis, thiab lwm yam, kom cov khoom uas muaj cov khoom zoo thiab kev ua tau zoo tuaj yeem npaj tau.
Lub sij hawm xa tuaj: Plaub Hlis-25-2024