Dab tsi yog qhov cuam tshuam ntawm cov ntxhiab tsw loj ntawm hydroxypropyl methylulose:
Synthesis ntawm hydroxypropylulcellulose: Kho cov ntaub ntawv refined nrog lye ntawm 35-40 ° Tso cov alkali mus rau hauv lub nroog Etherification, ntxiv tshuaj pleev antylene oxide thiab methyl ntawm 50-80 ° C rau 5-80 ° C rau 5-80 °, qhov siab tshaj plaws yog hais txog 1.8MPA. Tom qab ntawd ntxiv qhov tsim nyog ntawm hydrochloric acid thiab oxalic acid rau cov dej kub ntawm 90 ° C kom ntxuav cov khoom kom nthuav cov ntim. Lub cev qhuav dej hauv ib qho kev tswj hwm. Ntxuav nrog dej kom txog thaum nruab nrab. Thaum noo noo cov ntsiab lus ntawm cov khoom yog qis dua 60%, qhuav nws nrog cov huab cua kub kub ntawm 130 ° C kom txog thaum cov ntsiab lus noo noo yog qis dua 5%.
HPMC tau tsim los ntawm cov txheej txheem hnyav siv tau toluene thiab isopropanol raws li cov kuab tshuaj. Yog hais tias kev ntxuav tsis zoo, muaj ib co tsaus muag yuav nyob. Tam sim no, qhov zoo ntawm domestic hydroxyprropylenose HPMC sib txawv, thiab tus nqi sib txawv rau cov neeg siv khoom los ua qhov yog. Qhov no yog qhov teeb meem ntawm cov txheej txheem ntxuav, nws tsis cuam tshuam rau kev siv thiab tsis muaj teeb meem, Ntshiab HPMC yuav tsum tsis hnov ntxhiab ammonia, hmoov txhuv nplej siab thiab dej cawv; Adulterated HPMC feem ntau hnov tsw ntxhiab txhua yam tsw ntxhiab tsw, txawm tias nws yog tasteless, nws yuav hnov hnyav. Txawm li cas los xij, cov hydroxypropy kasthylcellose tsim los ntawm ntau cov tuam ntxhab muaj qhov tsis hnov tsw tshwj xeeb thiab kev hnov tsw. Qhov zoo yog yeej tsis tau nce rau par.
Hypromellose tau txais los ntawm impromeakating cov paj rwb refined nrog kua tsis tshua muaj qoob loo, tom qab ntawd etheraling cov tshuaj tiv thaiv, thiab lwm yam kom tau cov khoom tiav. Zoo, yuav muaj tus ntxhiab, yog li cov neeg siv tuaj yeem siv nws nrog kev ntseeg siab.
Lub Sijhawm Post: Jun-09-2023