Kev kho kom zoo ntawm Hydroxyethyl cellulose

Kev kho kom zoo ntawm Hydroxyethyl cellulose

Hydroxyethyl cellulose (HEC) yog cov dej-soluble polymer uas tau siv dav hauv ntau yam lag luam, suav nrog kev tsim kho, kev saib xyuas tus kheej, thiab tshuaj. Nws yog tsim los ntawm kev hloov kho tshuaj ntawm cellulose, uas koom nrog kev hloov ntawm hydroxyl pawg ntawm cov cellulose saw nrog hydroxyethyl pawg. Qhov degree ntawm kev hloov pauv (DS) ntawm HEC tuaj yeem sib txawv ntawm 1.5 txog 2.8, nyob ntawm daim ntawv thov.

Kev tsim khoom ntawm HEC suav nrog ntau cov kauj ruam ua kom zoo kom ntseeg tau qhov zoo thiab sib xws ntawm cov khoom kawg. Cov kauj ruam no suav nrog:

1. Cellulose purification: Thawj kauj ruam hauv HEC ntau lawm yog kev ua kom huv ntawm cellulose. Qhov no suav nrog kev tshem tawm cov impurities, xws li lignin thiab hemicellulose, los ntawm cellulose qhov chaw, uas tuaj yeem yog ntoo pulp lossis paj rwb linters. Cov txheej txheem purification tuaj yeem koom nrog ob peb kauj ruam, xws li tshuaj dawb, ntxuav, thiab lim, nyob ntawm seb qhov zoo ntawm cov cellulose.
2. Kev kho Alkali: Cov purified cellulose yog tom qab ntawd kho nrog cov tshuaj alkali, xws li sodium hydroxide lossis potassium hydroxide, los tsim alkali cellulose. Cov kauj ruam no yog tsim nyog los npaj cov cellulose rau cov kauj ruam tom ntej, uas yog etherification.
3. Etherification: Cov alkali cellulose yog ces reacted nrog ethylene oxide los tsim HEC. Cov tshuaj tiv thaiv no feem ntau yog ua nyob rau hauv lub xub ntiag ntawm ib tug catalyst, xws li sodium hydroxide los yog sodium methylate, nyob rau hauv siab kub thiab siab. Cov tshuaj tiv thaiv lub sij hawm thiab qhov kub thiab txias tau ua tib zoo tswj kom ua tiav qhov kev xav tau ntawm kev hloov pauv.
4. Neutralization: Tom qab cov tshuaj tiv thaiv etherification, HEC yog neutralized nrog cov kua qaub, xws li acetic acid lossis citric acid, los kho cov pH mus rau qhov nruab nrab. Cov kauj ruam no yog tsim nyog los tiv thaiv HEC los ntawm kev degradation dhau sijhawm.
5. Ntxuav thiab ziab: HEC yog tom qab ntawd ntxuav thiab ziab kom tshem tawm cov khoom seem thiab cov dej noo. Cov txheej txheem ziab yog feem ntau ua tiav ntawm qhov kub qis los tiv thaiv HEC los ntawm degrading.
6. Kev Tswjhwm Zoo: Cov kauj ruam kawg hauv HEC ntau lawm yog kev tswj kom zoo. Lub HEC raug kuaj rau ntau yam tsis muaj, xws li viscosity, noo noo cov ntsiab lus, thiab purity, kom ntseeg tau tias nws ua tau raws li qhov xav tau tshwj xeeb rau daim ntawv thov.

Ntxiv rau cov kauj ruam no, muaj ntau yam uas tuaj yeem cuam tshuam qhov zoo thiab kev ua haujlwm ntawm HEC, suav nrog:

1. Degree ntawm kev hloov pauv: Qib ntawm kev hloov pauv (DS) ntawm HEC tuaj yeem cuam tshuam rau nws cov solubility, viscosity, thiab gelation zog. Ib qho DS siab dua tuaj yeem ua rau muaj kua nplaum ntau dua thiab zoo li HEC, thaum DS qis dua tuaj yeem ua rau HEC ntau dua thiab dej.
2. Molecular Luj: Qhov hnyav molecular ntawm HEC tuaj yeem cuam tshuam nws cov viscosity thiab kev daws tus cwj pwm. Qhov hnyav molecular ntau dua tuaj yeem ua rau muaj kuab heev thiab zoo li HEC, thaum qhov hnyav dua molecular tuaj yeem ua rau HEC ntau dua thiab dej.
3. Purity: Lub purity ntawm HEC tuaj yeem cuam tshuam rau nws qhov kev ua tau zoo thiab ruaj khov. Cov impurities, xws li residual alkali lossis catalyst, tuaj yeem degrade HEC thaum lub sij hawm thiab cuam tshuam rau nws cov solubility thiab viscosity.
4. pH: Lub pH ntawm cov tshuaj HEC tuaj yeem cuam tshuam rau nws qhov ruaj khov thiab viscosity. Ib qho pH uas siab dhau lossis qis dhau tuaj yeem ua rau HEC degrade lossis poob nws cov viscosity.

HEC feem ntau yog siv los ua cov thickener, binder, thiab emulsifier hauv ntau yam lag luam, suav nrog kev tsim kho, kev saib xyuas tus kheej, thiab tshuaj. Hauv kev tsim kho kev lag luam, HEC yog siv los ua cov khoom ntxiv hauv cov khoom siv cement los txhim kho kev ua haujlwm, dej tuav, thiab nplaum lub zog. Hauv cov khoom tu tus kheej, HEC yog siv los ua cov thickener thiab stabilizer

txhawm rau txhim kho kev ntxhib los mos thiab ruaj khov ntawm cov qauv, xws li tshuaj zawv plaub hau, tshuaj pleev, thiab tshuaj pleev. Hauv kev lag luam kws tshuaj, HEC yog siv los ua ib qho kev sib khi thiab disintegrant hauv cov ntsiav tshuaj formulations.

Txhawm rau kom ntseeg tau qhov kev ua tau zoo ntawm HEC hauv cov ntawv thov no, nws yog ib qho tseem ceeb uas yuav tsum tau siv cov khoom zoo uas tau ua kom zoo dua qub thiab sim ua kom tau raws li qhov yuav tsum tau ua. Ntxiv nrog rau cov txheej txheem kho kom zoo tau piav qhia saum toj no, cov tuam txhab kuj tseem tuaj yeem siv cov txheej txheem ntxiv, xws li kev pom, txhawm rau ua kom huv thiab ua kom zoo dua HEC.

Zuag qhia tag nrho, kev kho kom zoo ntawm HEC yog ib kauj ruam tseem ceeb hauv nws cov khoom tsim los xyuas kom meej tias cov khoom kawg ua tau raws li qhov xav tau tshwj xeeb rau daim ntawv thov. Cov txheej txheem cuam tshuam nrog ob peb kauj ruam, suav nrog kev ua kom huv ntawm cellulose, kho alkali, etherification, neutralization, ntxuav thiab ziab, thiab kev tswj kom zoo. Cov qib ntawm kev hloov pauv, qhov hnyav molecular, purity, thiab pH ntawm HEC tuaj yeem cuam tshuam rau nws cov kev ua tau zoo thiab kev ruaj ntseg, thiab cov tuam ntxhab yuav tsum ua tib zoo tswj cov khoom no los tsim cov khoom zoo. Nrog rau kev kho kom zoo thiab kev tswj xyuas kom zoo, HEC tuaj yeem muab cov khoom muaj txiaj ntsig thiab cov txiaj ntsig hauv ntau yam kev siv.