Cov ntxhiab tsw ntawm hydroxypropyl methylcellulose (HPMC) cuam tshuam li cas?

Yuav ua li cas txiav txim siab qhov zoo ntawm hydroxypropyl methylcellulose (HPMC) yog ib lo lus nug uas ntau tus neeg muas zaub thiab cov phooj ywg muaj kev txhawj xeeb ntau dua. Niaj hnub no, Xinhe Shanda Cellulose piav qhia txog yuav ua li cas txiav txim qhov zoo ntawm hydroxypropyl methylcellulose (HPMC) Txiav txim siab qhov zoo ntawm cov khoom:

Ua ntej tshaj plaws, peb yuav tsum nkag siab txog cov txheej txheem tsim khoom ntawm hydroxypropyl methylcellulose:

Hydroxypropyl methylcellulose, tseem hu ua hypromellose thiabcellulose hydroxypropyl methyl ether, yog ua los ntawm cov paj rwb ntshiab heev cellulose li raw khoom, uas yog tshwj xeeb etherified nyob rau hauv alkaline tej yam kev mob.

Lub synthesis ntawm hydroxypropyl methylcellulose: kho cov paj rwb refined cellulose nrog lye ntawm 35-40 ° C rau ib nrab ib teev, nias nws, zuaj cov cellulose, thiab lub hnub nyoog nws zoo ntawm 35 ° C kom qhov nruab nrab degree ntawm polymerization ntawm tau alkali. fiber ntau hauv qhov xav tau. Muab cov alkali fiber ntau tso rau hauv etherification kettle, ntxiv propylene oxide thiab methyl chloride ua ntu zus, thiab etherify ntawm 50-80 ° C rau 5 teev, qhov siab tshaj plaws yog li 1.8MPa. Tom qab ntawd ntxiv qhov tsim nyog ntawm hydrochloric acid thiab oxalic acid rau hauv dej kub ntawm 90 ° C los ntxuav cov khoom kom nthuav dav. Dehydrate hauv ib lub centrifuge. Ntxuav kom txog thaum nruab nrab, thiab thaum cov dej hauv cov khoom qis dua 60%, ziab nws nrog cov cua kub ntws ntawm 130 ° C mus rau cov ntsiab lus tsawg dua 5%.

HPMC tsim los ntawm txoj kev hnyav siv toluene thiab isopropanol ua cov kuab tshuaj. Yog tias kev ntxhua khaub ncaws tsis zoo, yuav muaj cov ntxhiab tsw tsw qab. Qhov no yog ib qho teeb meem ntawm cov txheej txheem ntxuav, thiab nws tsis cuam tshuam rau kev siv thiab tsis muaj teeb meem, tab sis qhov tseeb Hydroxypropyl methylcellulose ua los ntawm ntau lub tuam txhab muaj cov ntxhiab tsw tshwj xeeb thiab pungent tsw. Qhov zoo ntawm hom no yog twv yuav raug hu tsis tau raws li tus qauv.

Hypromellose yog refined paj rwb impregnated nrog ib tug tsis tshua muaj kua kom tau alkaline cellulose, ces ntxiv hnyav, etherification tus neeg sawv cev, toluene, thiab isopropanol rau etherification cov tshuaj tiv thaiv, thiab tau cov khoom tiav tom qab neutralization, ntxuav, ziab, thiab crushing. Tsis zoo, nws yuav tsw ntxhiab, yog li cov neeg siv tuaj yeem siv nrog kev ntseeg siab.