Cov txheej txheem ua kua-theem ntawm kev tsim cov Hydroxypropyl Methyl Cellulose (HPMC)

Hydroxypropyl methyl cellulose (HPMC) yog ib qho cellulose ether dav siv nyob rau hauv ntau yam kev lag luam thiab kev siv tshuaj vim nws zoo heev lub cev thiab tshuaj. HPMC feem ntau yog tsim los ntawm ntau txoj hauv kev, suav nrog cov txheej txheem ua kua-theem.

Cov txheej txheem ua kua-theem yog cov txheej txheem tshuaj lom neeg uas muaj cov tshuaj tiv thaiv ntawm methyl cellulose (MC) nrog propylene oxide (PO) thiab tom qab ntawd nrog propylene glycol (PG) nyob rau hauv qee yam mob. Cov txheej txheem suav nrog cov kauj ruam hauv qab no:

1. Kev npaj ntawm Methyl Cellulose (MC)

MC tau txais los ntawm kev kho cellulose nrog alkali thiab tom qab ntawd methylating nws nrog methyl chloride. Qhov degree ntawm kev hloov pauv (DS) ntawm MC txiav txim siab nws cov khoom thiab tuaj yeem tswj tau los ntawm kev sib txawv ntawm cov tshuaj tiv thaiv.

2. Kev npaj ntawm Propylene Oxide (PO)

PO yog npaj los ntawm oxidation ntawm propylene siv cua los yog oxygen nyob rau hauv lub xub ntiag ntawm ib tug catalyst. Cov tshuaj tiv thaiv yog nqa tawm ntawm qhov kub thiab txias kom ntseeg tau tias muaj txiaj ntsig zoo ntawm PO.

3. Cov tshuaj tiv thaiv MC nrog PO

Cov tshuaj tiv thaiv ntawm MC nrog PO yog ua nyob rau hauv lub xub ntiag ntawm ib tug catalyst thiab ib tug hnyav xws li toluene los yog dichloromethane. Cov tshuaj tiv thaiv yog exothermic thiab generates cua sov, uas yuav tsum tau tswj kom tsis txhob khiav tawm.

4. Kev npaj ntawm Propylene Glycol (PG)

PG yog npaj los ntawm hydrolysis ntawm propylene oxide siv dej los yog ib tug haum acid los yog lub hauv paus catalyst. Cov tshuaj tiv thaiv yog ua nyob rau hauv cov mob me kom tau txais txiaj ntsig siab ntawm PG.

5. Cov tshuaj tiv thaiv MC-PO nrog PG

Cov khoom MC-PO tom qab ntawd tau hnov ​​​​mob nrog PG nyob rau hauv muaj cov catalyst thiab cov kuab tshuaj xws li ethanol lossis methanol. Cov tshuaj tiv thaiv kuj yog exothermic thiab generates cua sov, uas yuav tsum tau tswj kom tsis txhob khiav tawm cov tshuaj tiv thaiv.

6. Ntxuav thiab ziab

Tom qab cov tshuaj tiv thaiv, cov khoom yog ntxuav nrog dej thiab qhuav kom tau HPMC. Cov khoom yog feem ntau purified siv ib tug series ntawm pom thiab centrifugation cov kauj ruam kom tshem tawm tej impurities.

Cov txheej txheem ua kua-theem muaj ntau qhov zoo dua lwm txoj hauv kev, suav nrog cov khoom lag luam siab, tus nqi qis, thiab kev ua kom yooj yim. Cov tshuaj tiv thaiv tuaj yeem nqa tawm hauv ib lub nkoj, txo qhov xav tau ntawm cov cuab yeej siv thiab cov txheej txheem.

Txawm li cas los xij, txoj kev tsim ua kua-theem kuj muaj qee qhov tsis zoo. Cov tshuaj tiv thaiv tuaj yeem tsim kom muaj cua sov, uas yuav tsum tau ua tib zoo tswj kom tsis txhob muaj teeb meem kev nyab xeeb. Kev siv cov kuab tshuaj kuj tuaj yeem ua rau muaj kev phom sij rau ib puag ncig thiab kev noj qab haus huv, thiab cov txheej txheem purification tuaj yeem siv sijhawm ntev thiab kim.

Hauv kev xaus, cov txheej txheem ua kua-theem yog ib txoj kev siv dav rau kev tsim HPMC. Cov txheej txheem suav nrog cov tshuaj tiv thaiv ntawm MC nrog PO thiab PG nyob rau hauv qee yam mob, ua raws li kev ua kom huv thiab ziab. Thaum cov txheej txheem muaj qee qhov tsis zoo, nws qhov zoo ua rau nws yog qhov kev xaiv nrov rau kev lag luam thiab kev siv tshuaj.