Cellulose ether muaj cov dej tuav zoo heev, uas tuaj yeem tiv thaiv cov dej hauv cov khib nyiab ntub dej los ntawm evaporating ntxov ntxov los yog absorbed los ntawm lub hauv paus txheej, thiab xyuas kom meej tias cov cement yog tag nrho hydrated, yog li thaum kawg xyuas kom meej cov neeg kho tshuab cov khoom ntawm mortar, uas yog tshwj xeeb tshaj yog pab tau. mus rau nyias-txheej mortar thiab dej-absorbing puag txheej los yog mortar tsim nyob rau hauv kub kub thiab qhuav tej yam kev mob.Cov dej tuav cov nyhuv ntawm cellulose ether tuaj yeem hloov cov txheej txheem tsim kho ib txwm muaj thiab txhim kho kev tsim kho.Piv txwv li, plastering kev tsim kho tuaj yeem nqa tawm ntawm cov dej-absorbing substrates yam tsis muaj pre-wetting.
Lub viscosity, ntau npaum li cas, ambient kub thiab molecular qauv ntawm cellulose ether muaj kev cuam tshuam zoo rau nws cov dej tuav kev ua haujlwm.Nyob rau tib lub sijhawm, qhov ntau dua qhov viscosity ntawm cellulose ether, qhov dej tuav tau zoo dua;qhov ntau npaum li cas, qhov zoo dua cov dej tuav.Feem ntau, ib qho me me ntawm cellulose ether tuaj yeem txhim kho cov dej tuav ntawm mortar.Thaum qhov ntau npaum li cas nce mus txog qhov tseeb Thaum cov qib dej tuav tau nce, qhov sib txawv ntawm cov dej tuav tau qeeb;Thaum lub ambient kub nce, cov dej tuav ntawm cellulose ether feem ntau txo qis, tab sis qee qhov hloov kho cellulose ethers kuj muaj cov dej tuav zoo dua nyob rau hauv qhov kub thiab txias;fibers nrog qis dua ntawm kev hloov Vegan ether muaj cov dej tuav tau zoo dua.
Cov pab pawg hydroxyl ntawm cellulose ether molecule thiab cov pa atom ntawm ether daim ntawv cog lus yuav koom nrog cov dej molecule los tsim ib daim ntawv cog lus hydrogen, tig cov dej dawb rau hauv cov dej khi, yog li ua lub luag haujlwm zoo hauv dej tuav;Cov dej molecule thiab cellulose ether molecular saw Interdiffusion tso cai rau cov dej molecules nkag mus rau sab hauv ntawm cellulose ether macromolecular saw thiab muaj zog binding rog, yog li tsim cov dej khi thiab entangled dej, uas txhim kho cov dej tuav ntawm cement slurry;cellulose ether txhim kho cov cement slurry tshiab.Lub zog rheological, ntxeem tau lub network qauv thiab osmotic siab los yog cov yeeb yaj kiab-forming zog ntawm cellulose ether cuam tshuam cov diffusion ntawm dej.
Cellulose ether endows cov ntaub ntub dej nrog cov viscosity zoo heev, uas tuaj yeem ua rau muaj peev xwm ua kom muaj peev xwm sib txuas ntawm cov mortar ntub thiab cov txheej txheej, thiab txhim kho kev ua haujlwm ntawm cov tshuaj khib nyiab.Nws yog dav siv nyob rau hauv plastering mortar, cib bonding mortar thiab sab nrauv phab ntsa rwb thaiv tsev system.Cov nyhuv thickening ntawm cellulose ether tuaj yeem ua rau kom muaj peev xwm tiv thaiv kev tawg thiab kev sib xyaw ntawm cov khoom sib xyaw tshiab, tiv thaiv cov khoom delamination, cais thiab los ntshav, thiab tuaj yeem siv rau hauv fiber ntau pob zeb, underwater pob zeb thiab nws tus kheej-compacting pob zeb.
Cov nyhuv thickening ntawm cellulose ether ntawm cov khoom siv cement los ntawm cov viscosity ntawm cellulose ether kua.Nyob rau tib lub sijhawm, qhov siab dua ntawm cov viscosity ntawm cellulose ether, qhov viscosity zoo dua ntawm cov khoom siv cement-based, tab sis yog tias cov viscosity siab dhau lawm, nws yuav cuam tshuam rau cov dej ntws thiab kev ua haujlwm ntawm cov khoom siv (xws li sticking plastering riam. ).Self-leveling mortar thiab self-compacting qhob, uas yuav tsum tau muaj fluidity, yuav tsum tau tsawg viscosity ntawm cellulose ether.Tsis tas li ntawd, cov nyhuv thickening ntawm cellulose ether yuav ua rau kom cov dej xav tau ntawm cov ntaub ntawv cement-based thiab ua kom cov qoob loo ntau ntxiv.
Lub viscosity ntawm cellulose ether kua yog nyob ntawm cov hauv qab no: molecular hnyav ntawm cellulose ether, concentration, kub, shear npaum li cas thiab xeem txoj kev.Raws li cov xwm txheej zoo ib yam, qhov hnyav dua molecular ntawm cellulose ether, ntau dua qhov viscosity ntawm cov tshuaj;qhov siab dua qhov concentration, qhov siab dua qhov viscosity ntawm cov tshuaj.Thaum siv nws, yuav tsum tau saib xyuas kom tsis txhob muaj ntau npaum li cas thiab cuam tshuam rau kev ua haujlwm ntawm mortar thiab pob zeb;cellulose ether Lub viscosity ntawm ether tov yuav txo nrog qhov nce ntawm qhov kub thiab txias, thiab qhov siab dua qhov concentration, ntau dua qhov kub ntawm qhov kub;cellulose ether kua feem ntau yog cov kua pseudoplastic nrog cov cuab yeej ntawm shear thinning, ntau dua shear npaum li cas thaum lub sij hawm kuaj, qhov me me viscosity, yog li ntawd, cohesion ntawm lub mortar yuav txo qis nyob rau hauv qhov kev txiav txim ntawm sab nraud quab yuam, uas muaj txiaj ntsig zoo rau cov viscosity. scraping kev tsim kho ntawm mortar, kom lub mortar muaj peev xwm ua haujlwm zoo thiab sib koom ua ke tib lub sijhawm;vim tias cov tshuaj cellulose ether tsis yog-Newtonian Rau cov kua dej, thaum cov kev sim, cov twj paj nruag thiab cov khoom siv los yog qhov chaw sim siv los ntsuas cov viscosity sib txawv, cov txiaj ntsig ntawm tib cov tshuaj cellulose ether yuav txawv heev.
Cellulose ether molecules tuaj yeem txhim kho qee cov dej molecules ntawm cov khoom tshiab ntawm lub periphery ntawm cov saw molecular, yog li ua kom cov viscosity ntawm cov tshuaj.Cov chains molecular ntawm cellulose ether yog intertwined los tsim ib tug peb-dimensional network qauv, uas yuav kuj ua rau nws aqueous tov muaj viscosity zoo.
High-viscosity cellulose ether aqueous tov muaj siab thixotropy, uas kuj yog ib tug tseem ceeb yam ntxwv ntawm cellulose ether.Aqueous kev daws teeb meem ntawm methyl cellulose feem ntau muaj pseudoplastic thiab non-thixotropic fluidity hauv qab nws gel kub, tab sis qhia Newtonian ndlwg zog ntawm qis shear tus nqi.Pseudoplasticity nce nrog qhov hnyav molecular lossis concentration ntawm cellulose ether, tsis hais hom kev hloov pauv thiab qib ntawm kev hloov pauv.Yog li ntawd, cellulose ethers ntawm tib qib viscosity, tsis hais mc, HPmc, HEmc, yuav nco ntsoov qhia tib yam rheological zog ntev npaum li qhov concentration thiab kub nyob twj ywm.Cov txheej txheem gels yog tsim thaum qhov kub thiab txias, thiab thixotropic flows tshwm sim heev.High concentration thiab tsawg viscosity cellulose ethers qhia thixotropy txawm nyob rau hauv lub gel kub.Cov cuab yeej no muaj txiaj ntsig zoo rau kev hloov kho ntawm qib thiab sagging hauv kev tsim kho ntawm lub tsev mortar.Nws yuav tsum tau piav qhia ntawm no tias qhov siab dua qhov viscosity ntawm cellulose ether, qhov dej tuav tau zoo dua, tab sis qhov siab dua qhov viscosity, qhov siab dua qhov txheeb ze molecular hnyav ntawm cellulose ether, thiab qhov sib thooj hauv nws cov solubility, uas muaj kev cuam tshuam tsis zoo. ntawm mortar concentration thiab kev tsim kho.Qhov siab dua qhov viscosity, qhov pom tseeb dua cov nyhuv thickening ntawm cov tshuaj khib, tab sis nws tsis yog proportional kiag li.Qee qhov nruab nrab thiab qis viscosity, tab sis hloov kho cellulose ether muaj kev ua tau zoo dua hauv kev txhim kho lub zog ntawm cov mortar ntub dej.Nrog rau qhov nce ntawm viscosity, cov dej tuav ntawm cellulose ether txhim kho.
Post lub sij hawm: Feb-28-2023