Cov cuab yeej tseem ceeb tshaj plaws ntawm cov tshuaj cellulose ether yog nws cov cuab yeej rheological. Cov khoom tshwj xeeb rheological ntawm ntau cov cellulose ethers ua rau lawv siv dav hauv ntau qhov chaw, thiab kev kawm txog rheological khoom muaj txiaj ntsig zoo rau kev txhim kho cov ntawv thov tshiab lossis kev txhim kho ntawm qee daim ntawv thov. Li Jing los ntawm Shanghai Jiao Tong University tau ua txoj kev tshawb fawb txog cov khoom rheological ntawmcarboxymethylcellulose (CMC), suav nrog kev cuam tshuam ntawm CMC cov qauv molecular tsis (molecular hnyav thiab degree ntawm kev hloov), concentration pH, thiab ionic zog. Cov txiaj ntsig kev tshawb fawb pom tau tias xoom-shear viscosity ntawm cov tshuaj nce ntxiv nrog qhov nce ntawm qhov hnyav molecular thiab qib ntawm kev hloov pauv. Qhov nce ntawm qhov hnyav molecular txhais tau tias kev loj hlob ntawm cov saw hlau molecular, thiab qhov yooj yim entanglement ntawm cov molecules nce viscosity ntawm cov tshuaj; qhov loj ntawm kev hloov pauv ua rau cov molecules ncab ntau dua hauv cov tshuaj. Lub xeev muaj nyob, lub ntim hydrodynamic kuj loj, thiab cov viscosity ua loj. Lub viscosity ntawm CMC aqueous tov nce nrog nce concentration, uas muaj viscoelasticity. Lub viscosity ntawm cov tshuaj txo qis nrog tus nqi pH, thiab thaum nws qis dua ib qho nqi, qhov viscosity nce me ntsis, thiab thaum kawg cov kua qaub dawb yog tsim thiab precipitated. CMC yog polyanionic polymer, thaum ntxiv monovalent ntsev ions Na +, K + ntaub thaiv npog, viscosity yuav txo raws li. Qhov sib ntxiv ntawm divalent cation Caz + ua rau viscosity ntawm cov tshuaj txo qis ua ntej thiab tom qab ntawd nce. Thaum cov concentration ntawm Ca2+ siab tshaj qhov taw tes stoichiometric, CMC molecules cuam tshuam nrog Ca2+, thiab ib qho superstructure muaj nyob rau hauv cov tshuaj. Liang Yaqin, North University of China, thiab lwm yam. siv txoj kev viscometer thiab viscometer rotational viscometer los ua kev tshawb fawb tshwj xeeb ntawm cov khoom rheological ntawm dilute thiab concentrated daws ntawm hloov hydroxyethyl cellulose (CHEC). Cov txiaj ntsig tau tshawb fawb pom tias: (1) Cationic hydroxyethyl cellulose muaj tus cwj pwm ntawm polyelectrolyte viscosity hauv cov dej ntshiab, thiab cov viscosity txo qis nrog kev nce siab. Lub intrinsic viscosity ntawm cationic hydroxyethyl cellulose nrog high degree ntawm kev hloov yog ntau dua li ntawm cationic hydroxyethyl cellulose nrog tsawg degree ntawm kev hloov. (2) Cov kev daws teeb meem ntawm cationic hydroxyethyl cellulose muaj cov yam ntxwv uas tsis yog-Newtonian kua thiab muaj cov yam ntxwv ntawm shear thinning: raws li cov tshuaj concentration nce, nws pom tseeb viscosity nce; nyob rau hauv ib tug tej yam concentration ntawm ntsev tov, CHEC pom meej viscosity Nws txo nrog qhov nce ntxiv ntsev concentration. Nyob rau hauv tib lub shear tus nqi, qhov pom tseeb viscosity ntawm CHEC hauv CaCl2 tov system yog qhov siab dua li ntawm CHEC hauv NaCl tov system.
Nrog rau kev tshawb nrhiav tob zuj zus thiab kev nthuav dav ntawm daim ntawv thov kev lag luam, cov khoom ntawm cov kev daws teeb meem sib xyaw ua ke ntawm cov cellulose ethers sib txawv kuj tau txais tib neeg txoj kev xav. Piv txwv li, sodium carboxymethyl cellulose (NACMC) thiab hydroxyethyl cellulose (HEC) yog siv los ua cov roj hloov chaw hauv cov roj av, uas muaj qhov zoo ntawm cov shear tsis kam, ntau cov khoom siv raw thiab tsis muaj kuab paug ib puag ncig, tab sis cov nyhuv ntawm kev siv lawv ib leeg tsis zoo tagnrho. Txawm hais tias yav tas los muaj viscosity zoo, nws yog yooj yim cuam tshuam los ntawm reservoir kub thiab salinity; Txawm hais tias tom kawg muaj qhov kub thiab txias tsis kam, nws lub peev xwm thickening tsis zoo thiab qhov ntau npaum li cas yog qhov loj. Cov kws tshawb fawb tau sib xyaw ob txoj kev daws teeb meem thiab pom tias cov viscosity ntawm cov tshuaj sib xyaw ua kom loj dua, qhov kub thiab txias tsis kam thiab ntsev kuj tau txhim kho rau qee yam, thiab cov txiaj ntsig ntawm daim ntawv thov tau txhim kho. Verica Sovilj et al. tau kawm txog tus cwj pwm rheological ntawm kev daws teeb meem sib xyaw ua ke ntawm HPMC thiab NACMC thiab anionic surfactant nrog lub viscometer rotational. Tus cwj pwm rheological ntawm lub cev yog nyob ntawm HPMC-NACMC, HPMC-SDS thiab NACMC- (HPMC- SDS) sib txawv tshwm sim ntawm.
Lub zog rheological ntawm cellulose ether cov kev daws teeb meem kuj cuam tshuam los ntawm ntau yam, xws li additives, sab nraud mechanical quab yuam thiab kub. Tomoaki Hino et al. tau kawm txog qhov sib ntxiv ntawm nicotine ntawm rheological zog ntawm hydroxypropyl methylcellulose. Ntawm 25C thiab qhov concentration qis dua 3%, HPMC nthuav tawm Newtonian kua cwj pwm. Thaum ntxiv nicotine, qhov viscosity nce, uas qhia tau hais tias nicotine nce qhov entanglement ntawmHPMCmolecules. Nicotine ntawm no nthuav tawm cov nyhuv salting uas ua rau gel point thiab pos huab point ntawm HPMC. Mechanical force xws li shear force kuj yuav muaj qee yam cuam tshuam rau cov khoom ntawm cellulose ether aqueous tov. Siv rheological turbidimeter thiab lub kaum sab xis me me lub teeb tawg, nws pom tau tias nyob rau hauv ib nrab dilute tov, nce tus nqi shear, vim shear mixing, qhov hloov kub ntawm qhov taw tes pos huab yuav nce.
Lub sij hawm xa tuaj: Plaub Hlis-28-2024