Synthesis thiab Rheological Properties ntawm Hydroxyethyl Cellulose Ether

Nyob rau hauv lub xub ntiag ntawm tus kheej-ua alkali catalyst, muaj hydroxyethyl cellulose reacted nrog N-(2,3-epoxypropyl) trimethylammonium chloride (GTA) cationization reagent los npaj high-substitution quaternary ammonium los ntawm txoj kev qhuav ntsev hom Hydroxyethyl cellulose ether (HEC). Cov teebmeem ntawm qhov piv ntawm GTA rau hydroxyethyl cellulose (HEC), qhov piv ntawm NaOH rau HEC, qhov ntsuas kub ntawm cov tshuaj tiv thaiv, thiab lub sijhawm tshuaj tiv thaiv ntawm cov tshuaj tiv thaiv kev ua haujlwm tau raug tshawb xyuas nrog cov phiaj xwm kev sim sib xws, thiab cov txheej txheem ua kom zoo tau txais los ntawm Monte Carlo simulation. Thiab cov tshuaj tiv thaiv kev ua haujlwm ntawm cationic etherification reagent nce mus txog 95% los ntawm kev kuaj xyuas. Nyob rau tib lub sijhawm, nws cov khoom rheological tau tham txog. Cov txiaj ntsig tau pom tias qhov kev daws teeb meem ntawmHEC pom cov yam ntxwv ntawm cov dej tsis-Newtonian, thiab nws cov viscosity pom tseeb tau nce nrog qhov nce ntawm cov tshuaj loj concentration; nyob rau hauv ib tug tej yam concentration ntawm ntsev tov, lub meej viscosity ntawmHEC txo nrog qhov nce ntxiv ntsev concentration. Nyob rau hauv tib tus nqi shear, qhov pom tseeb viscosity ntawmHEC nyob rau hauv CaCl2 tov system yog siab dua li ntawmHEC hauv NaCl solution system.

Cov lus tseem ceeb:Hydroxyethylcellulose ether; txheej txheem qhuav; rheological zog

Cellulose muaj cov yam ntxwv ntawm kev nplua nuj, biodegradability, biocompatibility thiab yooj yim derivatization, thiab yog ib qho kev tshawb fawb hotspot nyob rau hauv ntau lub teb. Cationic cellulose yog ib qho tseem ceeb ntawm cov neeg sawv cev ntawm cellulose derivatives. Ntawm cov cationic polymers rau cov khoom tiv thaiv tus kheej sau npe los ntawm CTFA ntawm Fragrance Industry Association, nws noj yog thawj. Nws tuaj yeem siv dav hauv cov plaub hau txias txias additives, softeners, drilling shale hydration inhibitors thiab cov ntshav los tiv thaiv coagulation thiab lwm yam teb.

Tam sim no, txoj kev npaj ntawm quaternary ammonium cationic hydroxyethyl cellulose ether yog ib txoj kev hnyav, uas yuav tsum tau muaj ntau ntawm cov organic solvents kim heev, raug nqi, tsis zoo, thiab ua paug rau ib puag ncig. Piv nrog rau txoj kev hnyav, txoj kev qhuav qhuav muaj qhov zoo ntawm cov txheej txheem yooj yim, kev ua haujlwm siab, thiab kev ua qias tuaj ib puag ncig. Hauv daim ntawv no, cationic cellulose ether tau tsim los ntawm txoj kev qhuav thiab nws tus cwj pwm rheological tau kawm.

1. Kev sim ib feem

1.1 Cov ntaub ntawv thiab cov tshuaj reagents

Hydroxyethyl cellulose (HEC cov khoom lag luam, nws cov qib molecular hloov pauv DS yog 1.8 ~ 2.0); cationization reagent N-(2,3-epoxypropyl) trimethylammonium chloride (GTA), npaj los ntawm epoxy chloride Propane thiab trimethylamine yog tus kheej tsim nyob rau hauv tej yam kev mob; tus kheej ua alkali catalyst; ethanol thiab glacial acetic acid yog analytically ntshiab; NaCl, KCl, CaCl2, thiab AlCl3 yog tshuaj dawb huv reagents.

1.2 Kev npaj ntawm quaternary ammonium cationic cellulose

Ntxiv 5g ntawm hydroxyethyl cellulose thiab ib qho tsim nyog tus nqi ntawm homemade alkali catalyst rau hauv lub cylindrical steel lub tog raj kheej nruab nrog ib tug stirrer, thiab do rau 20 feeb ntawm chav tsev kub; Tom qab ntawd ntxiv ib qho nyiaj ntawm GTA, txuas ntxiv nplawm rau 30 feeb ntawm chav tsev kub, thiab hnov ​​​​mob ntawm qee qhov kub thiab lub sijhawm, cov khoom siv raw khoom tseem ceeb raws li tau txais. Cov khoom nyoos yog tsau rau hauv cov tshuaj ethanol uas muaj qhov tsim nyog ntawm acetic acid, lim, ntxuav, thiab lub tshuab nqus tsev kom qhuav kom tau cov hmoov quaternary ammonium cationic cellulose.

1.3 Kev txiav txim siab ntawm nitrogen loj feem ntawm quaternary ammonium cationic hydroxyethyl cellulose

Qhov loj feem ntawm nitrogen hauv cov qauv yog txiav txim los ntawm txoj kev Kjeldahl.

2. Kev sim tsim thiab optimization ntawm qhuav synthesis txheej txheem

Cov qauv tsim qauv siv los tsim qhov kev sim, thiab qhov cuam tshuam ntawm qhov piv ntawm GTA rau hydroxyethyl cellulose (HEC), qhov piv ntawm NaOH rau HEC, qhov ntsuas kub thiab lub sijhawm tshuaj tiv thaiv ntawm cov tshuaj tiv thaiv kev ua haujlwm tau tshawb xyuas.

3. Kev tshawb fawb txog rheological zog

3.1 Kev cuam tshuam ntawm concentration thiab kev sib hloov ceev

Siv cov nyhuv ntawm shear npaum li cas ntawm qhov pom tseeb viscosity ntawmHEC Ntawm qhov sib txawv ntawm qhov sib txawv Ds = 0.11 ua piv txwv, nws tuaj yeem pom tau tias vim tias qhov shear tus nqi maj mam nce ntawm 0.05 mus rau 0.5 s-1, qhov pom tseeb viscosity ntawmHEC Cov tshuaj txo qis, tshwj xeeb tshaj yog ntawm 0.05 ~ 0.5s-1 pom meej viscosity poob qis los ntawm 160MPa·s rau 40MPa·s, shear thinning, qhia tias qhovHEC Cov tshuaj aqueous tau nthuav tawm cov khoom tsis yog-Newtonian rheological. Cov nyhuv ntawm kev siv shear kev nyuaj siab yog los txo cov kev sib cuam tshuam quab yuam ntawm cov khoom ntawm cov theem dispersed. Nyob rau hauv tej yam kev mob, lub zog ntau dua, qhov pom tseeb viscosity ntau dua.

Nws tseem tuaj yeem pom los ntawm qhov pom tseeb viscosities ntawm 3% thiab 4%HEC aqueous cov ntsiab lus uas cov huab hwm coj concentration yog feem 3% thiab 4% ntawm qhov sib txawv shear tus nqi. Qhov pom tseeb viscosity ntawm cov tshuaj qhia tau hais tias nws cov viscosity-nce peev xwm nce nrog cov concentration. Yog vim li cas yog vim li cas cov concentration nce nyob rau hauv cov kev daws teeb meem, kev sib nrig sib repulsion ntawm lub molecules ntawm lub ntsiab saw ntawm.HEC thiab nruab nrab ntawm cov saw hlau molecular nce, thiab pom meej viscosity nce.

3.2 Cov nyhuv ntawm qhov sib txawv ntawm cov ntsev ntxiv

Qhov concentration ntawmHEC tau kho ntawm 3%, thiab cov txiaj ntsig ntawm kev ntxiv ntsev NaCl ntawm cov khoom viscosity ntawm cov tshuaj tau tshawb xyuas ntawm cov nqi sib txawv.

Nws tuaj yeem pom los ntawm cov txiaj ntsig tau tias qhov pom tseeb viscosity txo qis nrog qhov nce ntxiv ntawm ntsev ntxiv, uas qhia pom pom tseeb polyelectrolyte phenomenon. Qhov no yog vim hais tias ib feem ntawm Na + nyob rau hauv cov ntsev tov yog khi rau cov anion ntawm lubHEC sab saw. Qhov ntau dua qhov concentration ntawm cov ntsev ntsev, qhov ntau dua qhov nruab nrab ntawm qhov nruab nrab lossis tiv thaiv ntawm polyion los ntawm kev tawm tsam, thiab txo cov electrostatic repulsion, ua rau txo qis ntawm cov nqi ntawm cov polyion. , cov saw hlau polymer shrinks thiab curls, thiab pom meej concentration txo.

3.3 Cov txiaj ntsig ntawm cov ntsev sib txawv ntxiv rau

Nws tuaj yeem pom los ntawm kev cuam tshuam ntawm ob qhov sib txawv ntxiv ntsev, Nacl thiab CaCl2, ntawm qhov pom tseeb viscosity ntawmHEC Kev daws teeb meem uas pom meej viscosity txo qis nrog qhov sib ntxiv ntawm cov ntsev ntxiv, thiab ntawm tib tus nqi shear, qhov pom tseeb viscosityHEC Kev daws teeb meem hauv CaCl2 kev daws teeb meem Qhov pom meej viscosity siab dua li ntawmHEC kev daws teeb meem hauv NaCl kua system. Yog vim li cas yog tias calcium ntsev yog divalent ion, thiab nws yooj yim dua los khi rau ntawm Cl- ntawm polyelectrolyte sab saw. Kev sib xyaw ua ke ntawm pawg quaternary ammonium rauHEC Nrog Cl- yog txo, thiab shielding tsawg dua, thiab tus nqi ceev ntawm cov saw hlau polymer yog siab dua, ua rau cov electrostatic repulsion ntawm cov saw hlau polymer loj dua, thiab cov saw hlau polymer yog stretched, yog li qhov pom tseeb viscosity siab dua.

4. Cov lus xaus

Kev npaj qhuav ntawm kev hloov pauv cationic cellulose yog ib qho kev npaj zoo tshaj plaws nrog kev ua haujlwm yooj yim, kev ua haujlwm siab, thiab muaj kuab paug tsawg, thiab tuaj yeem zam kev siv hluav taws xob ntau, kev ua qias tuaj ib puag ncig, thiab toxicity tshwm sim los ntawm kev siv cov kuab tshuaj.

Kev daws ntawm cationic cellulose ether nthuav tawm cov yam ntxwv ntawm cov kua dej uas tsis yog-Newtonian thiab muaj cov yam ntxwv ntawm shear thinning; Raws li kev daws teeb meem loj concentration nce, nws pom tseeb viscosity nce; nyob rau hauv ib tug tej yam concentration ntawm ntsev tov,HEC Pom meej viscosity nce nrog nce thiab txo. Nyob rau hauv tib tus nqi shear, qhov pom tseeb viscosity ntawmHEC nyob rau hauv CaCl2 tov system yog siab dua li ntawmHEC hauv NaCl solution system.