Txoj kev tsim cov alkaline immersion yog ib txoj hauv kev los ua hydroxypropyl methyl cellulose (HPMC). Txoj kev no suav nrog cov tshuaj tiv thaiv cellulose nrog sodium hydroxide (NaOH) thiab tom qab ntawd nrog propylene oxide (PO) thiab methyl chloride (MC) nyob rau hauv qee yam mob.
Txoj kev alkaline immersion muaj qhov zoo ntawm kev tsim HPMC nrog kev hloov pauv siab (DS), uas txiav txim siab nws cov khoom xws li solubility, viscosity, thiab gelation. Txoj kev muaj cov kauj ruam hauv qab no:
- Kev npaj ntawm Cellulose
Cellulose yog tau los ntawm tej qhov chaw xws li ntoo, paj rwb, los yog lwm yam khoom siv cog. Cov cellulose yog thawj purified thiab tom qab ntawd kho nrog NaOH los tsim sodium cellulose, uas yog ib qho reactive intermediate nyob rau hauv zus tau tej cov HPMC.
- Cov tshuaj Sodium Cellulose nrog Propylene Oxide (PO)
Sodium cellulose yog tom qab ntawd ua rau PO nyob rau hauv lub xub ntiag ntawm ib tug catalyst xws li tetramethylammonium hydroxide (TMAH) los yog sodium hydroxide (NaOH) ntawm qhov kub thiab txias. Cov tshuaj tiv thaiv ua rau tsim cov hydroxypropyl cellulose (HPC).
- Cov tshuaj tiv thaiv HPC nrog Methyl Chloride (MC)
Tom qab ntawd HPC yuav ua rau MC nyob rau hauv lub xub ntiag ntawm ib tug catalyst xws li sodium hydroxide (NaOH) los yog hydrochloric acid (HCl). Cov tshuaj tiv thaiv ua rau tsim cov hydroxypropyl methyl cellulose (HPMC).
- 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.
Txoj kev alkaline immersion muaj ntau qhov zoo dua lwm txoj hauv kev, suav nrog DS siab thiab purity, tsis tshua muaj nqi, thiab yooj yim scalability. Cov txheej txheem kuj tseem siv tau los tsim HPMC nrog cov khoom sib txawv los ntawm kev sib txawv ntawm cov tshuaj tiv thaiv xws li kub, siab, thiab concentration.
Txawm li cas los xij, txoj kev kuj muaj qee qhov tsis zoo. Kev siv NaOH thiab MC tuaj yeem ua rau muaj kev nyab xeeb thiab kev pheej hmoo ntawm ib puag ncig, thiab cov txheej txheem tsim khoom tuaj yeem siv sijhawm ntev thiab xav tau ntau lub zog.
Hauv kev xaus, alkaline immersion ntau lawm txoj kev yog ib txoj kev dav siv los ua HPMC. Cov txheej txheem suav nrog cov tshuaj tiv thaiv ntawm cellulose nrog NaOH, PO, thiab MC 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.
Post lub sij hawm: Apr-23-2023