Lub luag haujlwm ntawm cellulose ether nyob rau hauv mortar yog: dej tuav, nce cohesion, thickening, cuam tshuam lub sij hawm teem, thiab huab cua-entraining zog. Vim yog cov yam ntxwv no, nws muaj qhov chaw siv dav hauv cov khoom siv mortar.
1. Cov dej tuav ntawm cellulose ether yog cov yam ntxwv tseem ceeb tshaj plaws hauv kev siv tshuaj khib nyiab.
Lub ntsiab yam tseem ceeb cuam tshuam rau cov dej tuav ntawm cellulose ether: viscosity, particle loj, ntau npaum, active ingredient, dissolution tus nqi, dej tuav mechanism: cov dej tuav ntawm cellulose ether nws tus kheej yog los ntawm solubility thiab lub cev qhuav dej ntawm cellulose ether nws tus kheej. Txawm hais tias cellulose molecular saw muaj ntau ntawm hydroxyl pawg uas muaj zog hydration zog, nws tsis soluble hauv dej. Qhov no yog vim hais tias cov qauv cellulose muaj ib tug high degree ntawm crystallinity, thiab lub peev xwm hydration ntawm hydroxyl pawg ib leeg tsis txaus los rhuav tshem cov muaj zog intermolecular bonds. Hydrogen bonds thiab van der Waals rog, yog li nws tsuas yog o tab sis tsis yaj hauv dej. Thaum ib qho kev hloov pauv tau nkag mus rau hauv cov saw hlau molecular, tsis yog cov khoom siv hloov pauv tsuas yog rhuav tshem cov ntawv cog lus hydrogen, tab sis kuj tseem cuam tshuam cov interchain hydrogen daim ntawv cog lus vim qhov sib txuas ntawm cov khoom sib hloov ntawm cov saw hlau uas nyob ib sab. Qhov loj dua qhov hloov pauv, qhov kev ncua deb ntawm cov molecules ntau dua, uas rhuav tshem cov nyhuv hydrogen. Qhov loj ntawm cellulose lattice, cov tshuaj nkag mus tom qab cellulose lattice nthuav dav, thiab cellulose ether ua dej-soluble, tsim cov tshuaj viscosity siab. Thaum qhov kub nce siab, cov dej ntawm cov polymer tsis muaj zog, thiab cov dej ntawm cov chains raug tsav tawm. Thaum lub cev qhuav dej txaus, cov molecules pib sib sau ua ke, tsim cov qauv peb-dimensional network thiab gel nag lossis daus.
(1) Cov nyhuv ntawm qhov loj me thiab sib xyaw lub sijhawm ntawm cellulose ether ntawm dej tuav
Nrog tib tus nqi ntawm cellulose ether, cov dej tuav ntawm mortar nce nrog qhov nce ntawm viscosity; qhov nce ntawm cov cellulose ether thiab qhov nce ntawm viscosity tsub kom cov dej tuav ntawm mortar. Thaum cov ntsiab lus ntawm cellulose ether ntau tshaj 0.3%, qhov kev hloov ntawm mortar dej tuav yuav tsum sib npaug. Lub peev xwm tuav dej ntawm mortar feem ntau tswj tau los ntawm lub sijhawm so, thiab cov cellulose ether dissolves sai dua, thiab cov dej khaws cia muaj peev xwm txhim kho sai dua.
(2) Kev cuam tshuam ntawm qib ntawm etherification ntawm cellulose ether thiab kub ntawm dej tuav
Raws li qhov kub nce siab, cov dej tuav tau txo qis, thiab qhov siab dua ntawm etherification ntawm cellulose ether, qhov zoo dua qhov kub siab dej tuav ntawm cellulose ether. Thaum siv, qhov kub ntawm cov khoom sib xyaw tshiab feem ntau yog qis dua 35 ° C, thiab nyob rau hauv cov huab cua tshwj xeeb, qhov kub tuaj yeem ncav cuag lossis tshaj 40 ° C. Hauv qhov no, cov qauv yuav tsum tau hloov kho thiab cov khoom lag luam nrog qib siab dua ntawm etherification yuav tsum raug xaiv. Ntawd yog, xav txog kev xaiv ib qho tsim nyog cellulose ether.
2. Cov nyhuv ntawm cellulose ether rau huab cua cov ntsiab lus ntawm mortar
Hauv cov khoom siv tshuaj khib nyiab qhuav, vim yog qhov sib ntxiv ntawm cellulose ether, qee qhov me me, sib xyaw ua ke thiab ruaj khov huab cua npuas tau nkag mus rau hauv cov khoom sib xyaw tshiab. Vim lub pob ua haujlwm ntawm cov pa npuas, lub mortar muaj kev ua haujlwm zoo thiab txo qhov torsion ntawm lub mortar. Txhaum thiab shrinkage, thiab nce tus nqi tso zis ntawm mortar.
3. Cov nyhuv ntawm cellulose ether ntawm cement hydration
Cellulose ether muaj retardation rau hydration ntawm cement-raws li mortar, thiab cov nyhuv retardation yog txhim kho nrog nce ntawm cellulose ether cov ntsiab lus. Cov yam ntxwv cuam tshuam ntawm cellulose ether ntawm cement hydration yog: ntau npaum li cas, qib ntawm etherification, hom cement.
Post lub sij hawm: Feb-02-2023