Hydroxyethyl cellulose (HEC) yog ib qho polymer uas tsis yog ionic, uas yaj tau hauv dej los ntawm cellulose, ib qho polymer uas tshwm sim hauv cov phab ntsa ntawm cov nroj tsuag. Nws yog siv dav hauv ntau yam lag luam xws li tshuaj, tshuaj pleev ib ce, xim, nplaum, thiab cov khoom noj vim nws cov khoom tshwj xeeb xws li thickening, stabilizing, thiab dej khaws cia. Txawm li cas los xij, kev sib tham txog tus nqi pH ntawm HEC xav tau kev nkag siab dav dua txog nws cov khoom, cov qauv, thiab cov ntawv thov.
Nkag Siab Txog Hydroxyethyl Cellulose (HEC):
1. Cov Qauv Tshuaj:
HEC yog synthesized los ntawm cov tshuaj tiv thaiv ntawm cellulose nrog ethylene oxide, ua rau muaj kev qhia txog hydroxyethyl pawg (-CH2CH2OH) rau ntawm cellulose backbone.
Qhov degree of substitution (DS) yog hais txog tus lej nruab nrab ntawm cov hydroxyethyl pawg ib chav glucose hauv cov saw cellulose thiab txiav txim siab cov khoom ntawm HEC. Cov nqi DS siab dua ua rau muaj kev nce ntxiv ntawm cov dej solubility thiab qis dua viscosity.
2. Cov Khoom:
HEC yog soluble hauv dej thiab tsim cov tshuaj ntshiab, uas ua rau nws haum rau ntau yam kev siv uas xav tau cov qauv pob tshab.
Nws ua rau pom tus cwj pwm pseudoplastic, txhais tau tias nws cov viscosity txo qis hauv qab kev ntxhov siab shear, ua rau yooj yim rau kev siv thiab tuav.
Qhov viscosity ntawm HEC cov kev daws teeb meem yog cuam tshuam los ntawm cov yam xws li concentration, kub, pH, thiab muaj cov ntsev lossis lwm yam khoom ntxiv.
3. Cov ntawv thov:
Cov Tshuaj: HEC yog siv los ua cov khoom siv tuab thiab stabilizer hauv cov tshuaj hauv qhov ncauj thiab tshuaj pleev ib ce xws li tshuaj pleev, tshuaj pleev, thiab tshuaj ncua.
Tshuaj pleev ib ce: Nws yog ib qho khoom xyaw uas siv ntau hauv cov khoom siv tu tus kheej xws li tshuaj zawv plaub hau, tshuaj pleev, thiab tshuaj pleev vim nws cov khoom ua kom tuab thiab emulsifying.
Xim thiab Txheej: HEC ntxiv rau cov xim, txheej, thiab cov nplaum kom tswj tau viscosity, txhim kho cov khoom ntws, thiab txhim kho cov yeeb yaj kiab tsim.
Kev Lag Luam Zaub Mov: Hauv cov khoom noj, HEC ua haujlwm ua ib qho thickener, stabilizer, thiab emulsifier hauv cov khoom xws li cov kua ntses, cov khaub ncaws, thiab cov khoom noj mis nyuj.
Tus nqi pH ntawm Hydroxyethyl Cellulose (HEC):
1. Kev Nyob Ntawm pH:
Lub pH ntawm cov kua uas muaj HEC tuaj yeem cuam tshuam nws tus cwj pwm thiab kev ua tau zoo hauv ntau yam kev siv.
Feem ntau, HEC ruaj khov hla ntau yam pH, feem ntau ntawm pH 2 thiab pH 12. Txawm li cas los xij, cov xwm txheej pH hnyav heev yuav cuam tshuam rau nws cov khoom thiab kev ruaj khov.
2. Cov teebmeem pH rau Viscosity:
Qhov viscosity ntawm HEC cov kev daws teeb meem tuaj yeem yog pH-nyob ntawm, tshwj xeeb tshaj yog ntawm cov nqi pH siab lossis qis.
Nyob ze ntawm qhov nruab nrab pH (pH 5-8), HEC cov kev daws teeb meem feem ntau qhia lawv qhov siab tshaj plaws viscosity.
Thaum pH qis heev lossis siab heev, cov cellulose backbone yuav raug hydrolysis, ua rau viscosity thiab stability txo qis.
3. Kev Kho pH:
Hauv cov qauv uas xav tau kev hloov kho pH, cov buffers feem ntau siv los tswj cov pH xav tau.
Cov buffers xws li citrate lossis phosphate buffers yog sib xws nrog HEC thiab pab tswj nws cov khoom hauv ib qho pH tshwj xeeb.
4. Kev Xav Txog Daim Ntawv Thov:
Cov neeg tsim qauv yuav tsum xav txog qhov pH sib xws ntawm HEC nrog lwm cov khoom xyaw hauv cov qauv.
Qee zaum, kev hloov kho rau pH ntawm cov qauv yuav tsum tau ua kom zoo dua qhov kev ua tau zoo ntawm HEC.
Hydroxyethyl cellulose (HEC) yog ib qho polymer uas siv tau ntau yam hauv ntau yam lag luam. Txawm hais tias nws qhov pH ruaj khov feem ntau muaj zog ntau yam, pH siab heev tuaj yeem cuam tshuam rau nws qhov kev ua tau zoo thiab kev ruaj khov. Kev nkag siab txog pH nyob ntawm HEC yog qhov tseem ceeb rau kev tsim cov khoom lag luam zoo thiab ruaj khov hauv cov tshuaj, tshuaj pleev ib ce, xim, nplaum, thiab cov khoom noj. Los ntawm kev xav txog pH sib xws thiab siv cov tswv yim tsim nyog, HEC tuaj yeem txuas ntxiv ua cov khoom xyaw muaj txiaj ntsig hauv ntau yam kev siv.
Lub sijhawm tshaj tawm: Plaub Hlis-15-2024