Yuav ua li cas npaj hydroxyethyl cellulose?

Hydroxyethyl celluloseyog ib qho tseem ceeb cellulose derivative. Vim muaj qhov zoo ntawm cov khoom siv raw khoom ntau, rov ua dua tshiab, biodegradable, tsis muaj tshuaj lom, zoo biocompatibility, thiab cov txiaj ntsig loj, nws txoj kev tshawb fawb thiab daim ntawv thov tau nyiam ntau qhov kev mloog zoo. . Tus nqi viscosity yog qhov ntsuas kev ua tau zoo tseem ceeb ntawm hydroxyethyl cellulose. Hauv daim ntawv no, hydroxyethyl cellulose nrog tus nqi viscosity siab dua 5 × 10 4mPa · s thiab tus nqi tshauv tsawg dua 0.3% tau npaj los ntawm cov kua-theem synthesis txoj kev los ntawm alkalization thiab etherification ob kauj ruam txheej txheem.

Cov txheej txheem alkalization yog cov txheej txheem npaj ntawm alkali cellulose. Hauv tsab ntawv no, muaj ob txoj kev alkalization siv. Txoj kev thawj zaug yog siv acetone ua ib qho diluent. Cov khoom siv cellulose raw yog basified ncaj qha hauv qee qhov concentration ntawm sodium hydroxide aqueous kua. Tom qab ua tiav qhov kev sib xyaw basification, tus neeg sawv cev etherifying ntxiv rau kom ua tiav qhov kev sib xyaw etherification ncaj qha. Txoj kev thib ob yog tias cov khoom siv cellulose raw yog alkalized hauv cov kua dej ntawm sodium hydroxide thiab urea, thiab alkali cellulose npaj los ntawm txoj kev no yuav tsum tau nias kom tshem tawm cov lye ntau dhau ua ntej qhov kev sib xyaw etherification. Cov alkali cellulose npaj los ntawm ntau txoj kev tau soj ntsuam los ntawm infrared spectroscopy thiab X-ray diffraction. Raws li cov khoom ntawm cov khoom npaj los ntawm qhov kev sib xyaw etherification, txoj kev xaiv tau txiav txim siab.

Yuav kom txiav txim siab tau qhov zoo tshaj plaws etherification synthesis txheej txheem, cov tshuaj tiv thaiv ntawm antioxidant, lye thiab glacial acetic acid hauv etherification reaction tau raug soj ntsuam ua ntej. Tom qab ntawd tsim cov kev sim ntawm ib qho kev tshuaj tiv thaiv, txiav txim siab cov yam ntxwv uas muaj feem cuam tshuam ntau dua rau kev ua haujlwm ntawm hydroxyethyl cellulose uas tau npaj tseg, thiab siv viscosity ntawm cov khoom 2% aqueous kua ua tus ntsuas siv. Cov txiaj ntsig ntawm kev sim qhia tau tias cov yam ntxwv xws li cov diluent xaiv, cov nqi ntawm ethylene oxide ntxiv, lub sijhawm alkalization, qhov kub thiab lub sijhawm ntawm thawj qhov kev tshuaj tiv thaiv, qhov kub thiab lub sijhawm ntawm qhov kev tshuaj tiv thaiv thib ob txhua yam muaj kev cuam tshuam loj rau kev ua haujlwm ntawm cov khoom. Ib qho kev sim orthogonal nrog xya yam ntxwv thiab peb theem tau kos, thiab cov kab nkhaus cuam tshuam los ntawm cov txiaj ntsig ntawm kev sim tuaj yeem soj ntsuam cov yam ntxwv tseem ceeb thiab theem nrab thiab qhov cuam tshuam ntawm txhua yam ntxwv. Yuav kom npaj cov khoom nrog cov nqi viscosity siab dua, ib qho kev sim zoo tshaj plaws tau tsim, thiab cov txheej txheem zoo tshaj plaws rau kev npaj hydroxyethyl cellulose thaum kawg tau txiav txim siab los ntawm cov txiaj ntsig ntawm kev sim.

Cov khoom ntawm cov khoom siv high-viscosity uas tau npaj tseghydroxyethyl cellulosetau raug tshuaj xyuas thiab sim, suav nrog kev txiav txim siab ntawm viscosity, cov tshauv ntsiab lus, lub teeb transmittance, cov dej noo, thiab lwm yam, los ntawm infrared spectroscopy, nuclear magnetic resonance, gas chromatography, X-ray diffraction, Thermogravimetric-differential thermal analysis thiab lwm txoj kev piav qhia tau siv los tshuaj xyuas thiab piav qhia txog cov khoom qauv, kev sib npaug ntawm cov khoom, molar substitution degree, crystallinity, thermal stability, thiab lwm yam. Cov txheej txheem sim xa mus rau ASTM cov qauv.

Hydroxyethyl cellulose, ib qho tseem ceeb cellulose derivative, tau nyiam mloog vim nws cov khoom siv raw khoom ntau, rov ua dua tshiab, biodegradable, nontoxic, biocompatible, thiab high yield. Lub viscosity ntawm hydroxyethyl cellulose yog ib qho cim tseem ceeb heev ntawm nws cov kev ua tau zoo. Lub viscosity ntawm hydroxyethyl cellulose npaj yog siab dua 5 × 10 4 mPa · s, thiab cov tshauv cov ntsiab lus tsawg dua 0.3%.

Hauv tsab ntawv no, hydroxyethyl cellulose uas muaj viscosity siab tau npaj los ntawm cov kua-theem synthesis txoj kev los ntawm alkalization thiab etherification. Cov txheej txheem alkalization yog kev npaj ntawm alkali cellulose. Xaiv los ntawm ob txoj kev alkalization. Ib qho yog tias cov khoom siv cellulose yog alkalized ncaj qha nrog acetone ua ib qho diluent hauv cov kua sodium hydroxide, thiab tom qab ntawd dhau los ua etherification reaction nrog tus neeg sawv cev etherifying. Qhov thib ob yog tias cov khoom siv cellulosic yog alkalized hauv cov kua sodium hydroxide thiab urea. Cov alkali ntau dhau hauv alkali cellulose yuav tsum tau tshem tawm ua ntej qhov reaction. Hauv tsab ntawv no, ntau yam alkali celluloses raug kawm los ntawm infrared spectroscopy thiab X-ray diffraction. Thaum kawg, txoj kev thib ob yog txais yuav raws li cov khoom ntawm cov khoom etherification.

Yuav kom txiav txim siab txog cov kauj ruam npaj ntawm etherification, cov tshuaj tiv thaiv ntawm antioxidant, alkali thiab glacial acetic acid hauv cov txheej txheem noj mov tau kawm. Cov yam tseem ceeb uas cuam tshuam rau kev npaj ntawm hydroxyethyl cellulose tau txiav txim siab los ntawm kev sim ib qho xwb. Raws li tus nqi viscosity ntawm cov khoom hauv 2% aqueous kua. Cov txiaj ntsig ntawm kev sim qhia tau hais tias qhov ntim ntawm diluent, qhov ntau ntawm ethylene oxide, lub sijhawm alkalization, qhov kub thiab lub sijhawm ntawm thawj thiab thib ob rehydration muaj kev cuam tshuam loj rau kev ua haujlwm ntawm cov khoom. Txoj kev ntawm xya yam thiab peb theem tau txais yuav los txiav txim siab txog txoj kev npaj zoo tshaj plaws.

Peb tshuaj xyuas cov khoom ntawm cov khoom npaj tauhydroxyethyl cellulose, suav nrog viscosity, tshauv, lub teeb transmittance, noo noo, thiab lwm yam. Cov qauv kev ua haujlwm, kev hloov pauv homogeneity, kev hloov pauv molarity, crystallinity thiab thermal stability tau tham los ntawm infrared, nuclear magnetic resonance, gas chromatography, X-ray diffraction, DSC thiab DAT, thiab cov txheej txheem sim tau txais yuav ASTM cov qauv.