Polycarboxylic acid dej reducer yog tsim los ntawm carboxylic acid uas muaj cov roj av tsis haum monomer copolymerization, yog li cov pob zeb ua kom cov dej txo qis, plam kev tiv thaiv, ntxiv dag zog, shrinkage thiab ib puag ncig tiv thaiv muaj qhov ua tau zoo ntawm cov dej ua haujlwm.
Poly carboxylic acid dej txo tus neeg sawv cev yog tus neeg sawv cev saum npoo, surfactant molecules tsim nrog hydrophilic pab pawg thiab hydrophobic pawg hauv ob ntu, pawg hydrophilic, ntxiv dej, taw tes rau kev daws, hydrophobic pawg rau huab cua, cov khoom ua kua lossis nonpolar kua thiab cov kev taw qhia, daim duab directional adsorption zaj duab xis txo thiab dej' s nto nro thiab interfacial nro.
Nws cov txheej txheem txiav txim siab yog tias thaum cov dej tsim hluav taws xob ntxiv rau cov cement slurry, hydrophobic pawg hauv cov qauv ntawm cov dej ntawm cov dej reducer yog adsorbed nyob rau saum npoo ntawm cement particle, txo lub zog lub zog.
Hydrophilic pab pawg rau aqueous tov, tsim ib lub qauv nyob rau sab saum npoo ntawm cov nplais MAAs lossis multimolecular adsorption zaj duab xis, saum npoo ntawm cov nplais cement nrog tib tus nqi, qhia cov repulsion, jianshuiji molecules adsorbed nyob rau saum npoo ntawm MAAs hais qhov chaw steric repulsion ntawm MAAs particle dispersion , rhuav tshem cov qauv ntawm cov cement flocculation, tso cov dej dawb ntau, ua kom lub zog ntawm cov pob zeb sib tov.
Polycarboxylic acid dej reducer nkag siab rau cov ntsiab lus alkali ntawm cov cement, kev sib raug zoo ntawm cov xis mas thiab polycarboxylic acid dej txo yog txiav txim siab los ntawm Lub Kaum ntawm rheology, muaj cov tshuaj tiv thaiv zoo alkali ntawm cov cement.
Thaum qes dhau lossis qis dua, qhov sib xyaw ntawm cov kav dej ua dej thiab cov cement yuav raug cuam tshuam tsis zoo.
Txhawm rau kom ua tau raws li qhov ntsuas qhov xav tau ntawm cov qis alkali xis mas, qee cov tuam txhab cement tsis tuaj yeem ncav cuag tus nqi zoo ntawm soluble alkali cov khoom hauv cov cement. Nyob rau hauv txoj kev no, tsis tsuas yog thaum cov ntsiab lus ntawm dej-txo tus neeg sawv cev tsis txaus, tab sis kuj thaum cov ntsiab lus me ntsis siab dua qhov chaw zaum, qhov sib cais loj thiab los ntshav yuav tshwm sim.
Cov ntsiab lus siab hauv alkali hauv cov cement yuav txo lub sijhawm teeb tsa thiab nce lub zog thaum ntxov.
