Lub mechanism ntawm thickeninghydroxyethyl celluloseyog kom nce qhov viscosity los ntawm kev tsim cov intermolecular thiab intramolecular hydrogen bonds, nrog rau hydration thiab saw entanglement ntawm molecular chains. Yog li ntawd, txoj kev thickening ntawm hydroxyethyl cellulose tuaj yeem faib ua ob yam: ib qho yog lub luag haujlwm ntawm intermolecular thiab intramolecular hydrogen bonds. Lub hydrophobic tseem ceeb saw txuas nrog cov dej molecules nyob ib puag ncig los ntawm hydrogen bonds, uas txhim kho qhov fluidity ntawm polymer nws tus kheej. Lub ntim ntawm cov khoom me me txo qhov chaw rau kev txav mus los dawb ntawm cov khoom me me, yog li ua rau kom muaj viscosity ntawm lub kaw lus; qhov thib ob, los ntawm kev entanglement thiab overlapping ntawm molecular chains, cov cellulose saw yog nyob rau hauv peb-dimensional network qauv hauv tag nrho lub kaw lus, yog li txhim kho viscosity.
Cia peb saib seb cellulose ua lub luag haujlwm li cas hauv kev ruaj khov ntawm lub kaw lus: ua ntej, lub luag haujlwm ntawm hydrogen bonds txwv tsis pub cov dej ntws dawb, ua lub luag haujlwm hauv kev khaws dej, thiab pab tiv thaiv kev sib cais dej; qhov thib ob, kev sib cuam tshuam ntawm cov saw hlau cellulose Lub lap entanglement tsim ib lub network sib txuas lossis thaj chaw sib cais ntawm cov pigments, fillers thiab emulsion particles, uas tiv thaiv kev sib sau ua ke.
Nws yog kev sib xyaw ua ke ntawm ob hom kev ua haujlwm saum toj no uas ua rau muaj peev xwmhydroxyethyl cellulosekom muaj peev xwm zoo heev los txhim kho kev ruaj khov ntawm kev khaws cia. Hauv kev tsim cov xim latex, HEC ntxiv thaum lub sijhawm ntaus thiab dispersing nce nrog rau kev nce ntawm lub zog sab nraud, qhov nrawm ntawm shear nce, cov molecules raug teeb tsa hauv kev coj ua kom sib luag rau qhov kev coj ua ntws, thiab lub kaw lus winding ntawm cov saw hlau molecular raug rhuav tshem, uas yooj yim rau kev swb nrog ib leeg, qhov system viscosity txo qis. Txij li thaum lub kaw lus muaj ntau yam khoom sib xyaw (pigments, fillers, emulsions), qhov kev npaj ua kom zoo no tsis tuaj yeem rov qab kho qhov xwm txheej ntawm kev sib txuas thiab sib tshooj txawm tias nws tau muab tso rau lub sijhawm ntev tom qab cov xim sib xyaw. Hauv qhov no, HEC tsuas yog vam khom hydrogen bonds. Cov nyhuv ntawm kev khaws dej thiab thickening txo qhov thickening efficiency ntawmHEC, thiab qhov kev koom tes ntawm lub xeev dispersion no rau qhov ruaj khov ntawm lub kaw lus kuj raug txo qis raws li. Txawm li cas los xij, cov HEC yaj tau sib xyaw ua ke hauv lub kaw lus ntawm qhov ceev qis dua thaum lub sijhawm tso tseg, thiab cov qauv network tsim los ntawm kev sib txuas ntawm HEC saw hlau tau puas tsuaj tsawg dua. Yog li qhia txog kev ua haujlwm thickening zoo dua thiab kev ruaj khov ntawm kev khaws cia. Nws yog qhov tseeb, qhov kev ua haujlwm tib lub sijhawm ntawm ob txoj kev thickening yog qhov tseem ceeb ntawm kev ua kom cov cellulose tuab thiab ua kom muaj kev ruaj khov ntawm kev khaws cia. Hauv lwm lo lus, lub xeev yaj thiab dispersed ntawm cellulose hauv dej yuav cuam tshuam loj heev rau nws cov nyhuv thickening thiab nws qhov kev koom tes rau kev ruaj khov ntawm kev khaws cia.
Lub sijhawm tshaj tawm: Plaub Hlis-25-2024