Cellulose ethertuaj yeem txhim kho qhov kev ua tau zoo ntawm cov mortar ntub, thiab yog ib qho khoom siv tseem ceeb uas cuam tshuam rau kev ua tau zoo ntawm cov mortar. Kev xaiv cov cellulose ethers ntawm ntau hom sib txawv, viscosities sib txawv, qhov loj me ntawm cov khoom sib txawv, qib sib txawv ntawm viscosity thiab cov nqi ntxiv yuav muaj qhov cuam tshuam zoo rau kev txhim kho qhov kev ua tau zoo ntawm cov hmoov mortar qhuav.
Kuj tseem muaj kev sib raug zoo ntawm qhov sib xws ntawm cov cement paste thiab cov koob tshuaj ntawm cellulose ether. Cellulose ether tuaj yeem ua rau cov mortar viscosity ntau ntxiv. Qhov ntau dua qhov koob tshuaj, qhov ntau dua qhov cuam tshuam. Cov kua dej cellulose ether uas muaj viscosity siab muaj thixotropy siab, uas kuj yog ib qho tseem ceeb ntawm cellulose ether.
Qhov ua kom tuab nyob ntawm qib polymerization ntawm cellulose ether, kev daws teeb meem concentration, shear rate, kub thiab lwm yam mob. Lub zog gelling ntawm cov tshuaj yog tshwj xeeb rau alkyl cellulose thiab nws cov derivatives hloov kho. Cov khoom gelation muaj feem cuam tshuam rau qib ntawm kev hloov pauv, kev daws teeb meem concentration thiab cov khoom ntxiv. Rau hydroxyalkyl hloov kho derivatives, cov khoom gel kuj muaj feem cuam tshuam rau qib hloov kho ntawm hydroxyalkyl. 10% -15% cov tshuaj tuaj yeem npaj rau MC thiab HPMC uas muaj viscosity qis, 5% -10% cov tshuaj tuaj yeem npaj rau MC thiab HPMC uas muaj viscosity nruab nrab, thiab 2% -3% cov tshuaj tsuas yog tuaj yeem npaj rau MC thiab HPMC uas muaj viscosity siab. Feem ntau qhov kev faib tawm viscosity ntawm cellulose ether kuj tau muab qib los ntawm 1% -2% cov tshuaj.
Qhov hnyav molecular siabcellulose ethermuaj kev ua haujlwm siab thickening. Cov polymers nrog cov qhov hnyav molecular sib txawv muaj cov viscosities sib txawv hauv tib qho kev daws teeb meem concentration. Qib siab. Lub hom phiaj viscosity tsuas yog ua tiav los ntawm kev ntxiv ntau ntawm cov cellulose ether qis molecular hnyav. Nws cov viscosity muaj kev vam khom me ntsis ntawm qhov shear rate, thiab cov viscosity siab ncav cuag lub hom phiaj viscosity, thiab qhov xav tau ntxiv yog me me, thiab cov viscosity nyob ntawm qhov ua haujlwm thickening. Yog li ntawd, kom ua tiav qee qhov sib xws, ib qho ntau ntawm cellulose ether (kev sib xyaw ntawm cov tshuaj) thiab cov viscosity ntawm cov tshuaj yuav tsum tau lees paub. Qhov kub ntawm cov tshuaj gel kuj txo qis linearly nrog kev nce ntawm qhov concentration ntawm cov tshuaj, thiab gels ntawm chav tsev kub tom qab ncav cuag qee qhov concentration. Qhov concentration gelling ntawm HPMC yog qhov siab ntawm chav tsev kub.
Lub sijhawm tshaj tawm: Plaub Hlis-28-2024