Focus on Cellulose ethers

Dab tsi yog qhov cuam tshuam rau lub teeb xa hluav taws xob ntawm hydroxypropyl methylcellulose?

Lub teeb kis ntawm hydroxypropyl methylcellulose feem ntau cuam tshuam los ntawm cov ntsiab lus hauv qab no:

1. Qhov zoo ntawm cov khoom siv raw.

Qhov thib ob, cov nyhuv ntawm alkalization.

3. Txheej txheem piv

4. Qhov hnyav ntawm qhov hnyav

5. Cov nyhuv ntawm neutralization

Qee cov khoom muaj huab zoo li cov mis nyuj tom qab lawv yaj, qee qhov yog mis nyuj dawb, qee qhov daj, thiab qee qhov yog qhov tseeb thiab pob tshab… Txhawm rau daws qhov teeb meem, kho los ntawm cov ntsiab lus hauv qab no. Qee zaum acetic acid tuaj yeem cuam tshuam rau lub teeb xa hluav taws xob. Nws yog qhov zoo tshaj plaws los siv acetic acid tom qab dilution. Qhov kev cuam tshuam loj tshaj plaws yog seb cov tshuaj tiv thaiv puas sib npaug thiab seb qhov kev sib piv ntawm qhov system puas ruaj khov (qee cov ntaub ntawv muaj cov dej noo thiab cov ntsiab lus tsis ruaj khov, xws li cov kuab tshuaj siv rau kev rov ua dua tshiab). Qhov tseeb, ntau yam cuam tshuam. Yog tias cov cuab yeej ruaj khov thiab cov neeg ua haujlwm tau txais kev cob qhia zoo, kev tsim khoom yuav tsum ruaj khov heev. Lub teeb xa hluav taws xob yuav tsis pub dhau qhov ntau ntawm ± 2%, thiab qhov hloov pauv sib txawv ntawm cov pab pawg hloov pauv yuav tsum tau tswj kom zoo. Es tsis txhob uniformity, lub teeb transmittance yeej yuav zoo.

 

Cov yam ntxwv cuam tshuam rau viscosity ntawm hydroxypropyl methylcellulose:

High-viscosity hydroxypropyl methylcellulose tsis tuaj yeem tsim cov cellulose siab heev tsuas yog los ntawm kev nqus thiab hloov nitrogen hauv ntau lawm. Feem ntau, kev tsim cov high-viscosity cellulose hauv Suav teb tsis tuaj yeem tswj tau. Txawm li cas los xij, yog tias cov cuab yeej ntsuas pa oxygen tuaj yeem ntsia tau rau hauv lub lauj kaub, qhov tsim ntawm nws cov viscosity tuaj yeem tswj tau.

ua. Tsis tas li ntawd, xav txog kev hloov ceev ntawm nitrogen, nws yog ib qho yooj yim los tsim cov khoom muaj viscosity txawm tias lub kaw lus airtight zoo li cas. Tau kawg, cov degree ntawm polymerization ntawm refined paj rwb kuj tseem ceeb heev. Yog tias qhov ntawd tsis ua haujlwm, ces ua nrog hydrophobic koom haum. Muaj cov koom haum ua haujlwm hauv cheeb tsam no hauv Suav teb. Dab tsi ntawm koom haum tus neeg sawv cev xaiv muaj kev cuam tshuam zoo rau kev ua haujlwm ntawm cov khoom kawg. Lub residual oxygen nyob rau hauv lub reactor ua rau degradation ntawm cellulose thiab txo qhov hnyav ntawm molecular, tab sis cov residual oxygen yog txwv, tsuav yog cov tawg molecules yog reconnected, nws tsis yog nyuaj rau siab viscosity. Txawm li cas los xij, tus nqi saturation muaj ntau ua nrog cov ntsiab lus ntawm hydroxypropyl. Qee lub chaw tsim khoom tsuas yog xav txo tus nqi thiab tus nqi, tab sis tsis kam ua kom cov ntsiab lus ntawm hydroxypropyl, yog li qhov zoo tsis tuaj yeem ncav cuag qib ntawm cov khoom txawv teb chaws zoo sib xws. Cov dej tuav tus nqi ntawm cov khoom muaj kev sib raug zoo nrog hydroxypropyl, tab sis nws kuj txiav txim siab nws cov dej tuav tus nqi, alkalization nyhuv, piv ntawm methyl chloride thiab propylene oxide, alkali concentration thiab dej tuav tus nqi rau tag nrho cov txheej txheem tshuaj tiv thaiv. Qhov piv rau cov paj rwb refined txiav txim siab qhov ua tau zoo ntawm cov khoom.


Post lub sij hawm: Mar-29-2023
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