Redispersible latex hmoov yog cov khoom siv organic gelling feem ntau. Nws yog cov hmoov uas tau los ntawm kev txau-qhuav ib lub polymer emulsion nrog polyvinyl cawv raws li kev tiv thaiv colloid. Cov hmoov no tuaj yeem sib npaug hauv dej tom qab sib ntsib dej. , tsim ib qho emulsion. Ntxiv cov hmoov av redispersible latex tuaj yeem txhim kho cov dej khaws cia ntawm cov cement mortar tshiab, nrog rau kev sib koom ua ke, kev yooj yim, impermeability thiab corrosion kuj ntawm hardened cement mortar.
Cov nyhuv ntawm latexr hmoov rau daim ntawv cog lus lub zog ntawm cov khoom siv cement
Emulsion thiab redispersible latex hmoov tuaj yeem tsim lub zog tensile siab thiab kev sib txuas ntawm cov ntaub ntawv sib txawv tom qab tsim cov yeeb yaj kiab, lawv tau siv los ua tus thib ob binder hauv mortar los ua ke nrog inorganic binder cement, cement thiab polymer raws li muab kev ua si tag nrho rau cov kev sib raug zoo los txhim kho lub kev ua haujlwm ntawm mortar. Los ntawm kev soj ntsuam lub microstructure ntawm cov khoom siv polymer-cement composite, nws ntseeg tau tias qhov sib ntxiv ntawm cov kua roj hmab redispersible latex tuaj yeem ua rau cov ntaub ntawv polymer ua ib zaj duab xis thiab ua ib feem ntawm lub qhov phab ntsa, thiab ua rau cov mortar tag nrho los ntawm lub zog sab hauv, uas txhim kho lub zog sab hauv ntawm lub mortar. Polymer lub zog, yog li txhim kho qhov tsis ua hauj lwm kev nyuaj siab ntawm lub mortar thiab ua rau qhov kawg strain. Qhov kev ua tau zoo mus ntev ntawm redispersible latex hmoov nyob rau hauv mortar tau kawm. Nws tau pom los ntawm SEM tias tom qab 10 xyoo, lub microstructure ntawm polymer nyob rau hauv mortar tsis tau hloov, thiab ruaj khov kev sib raug zoo, flexural thiab compressive tsis kam. lub zog thiab zoo tiv thaiv dej. Lub redispersible latex hmoov tau kawm txog kev tsim cov txheej txheem ntawm cov pobzeb nplaum lub zog, thiab pom tias tom qab cov polymer qhuav thiab tsim rau hauv cov yeeb yaj kiab, cov yeeb yaj kiab polymer tsim ib qho kev sib txuas ntawm cov mortar thiab cov pobzeb ntawm ib sab, thiab ntawm qhov Tsis tas li ntawd, cov mortar tshiab Lub nruab nrab polymer ua rau kom cov huab cua ntawm cov mortar thiab cuam tshuam rau kev tsim thiab wettability ntawm qhov chaw, thiab tom qab ntawd thaum lub sij hawm txheej txheem, cov polymer kuj muaj kev cuam tshuam zoo dua rau cov txheej txheem hydration thiab shrinkage ntawm cov cement hauv. tus binder, tag nrho cov no yuav pab txhim kho lub zog ntawm daim ntawv cog lus.
Ntxiv cov roj respersible latex hmoov rau hauv mortar tuaj yeem txhim kho kev sib raug zoo nrog lwm cov ntaub ntawv, vim tias hydrophilic latex hmoov thiab cov kua theem ntawm cov cement suspension nkag mus rau hauv cov pores thiab capillaries ntawm matrix, thiab cov hmoov latex nkag mus rau hauv cov pores thiab capillaries. . Cov zaj duab xis sab hauv yog tsim thiab khov kho adsorbed rau ntawm qhov chaw ntawm lub substrate, yog li ua kom muaj kev sib raug zoo ntawm cov khoom siv cementitious thiab substrate.
Kev ua kom zoo ntawm cov hmoov latex ntawm kev ua haujlwm ntawm mortar yog vim lub fact tias latex hmoov yog ib tug siab molecular polymer nrog polar pawg. Thaum cov hmoov latex tov nrog EPS hais, qhov tsis yog-polar ntu nyob rau hauv cov saw tseem ceeb ntawm latex hmoov polymer yuav lub cev adsorption yuav tshwm sim nrog cov tsis-polar nto ntawm EPS. Cov pawg polar nyob rau hauv cov polymer yog taw qhia sab nraud ntawm EPS hais, kom cov EPS hais hloov ntawm hydrophobicity mus rau hydrophilicity. Vim yog kev hloov kho ntawm EPS cov khoom los ntawm cov hmoov latex, nws daws qhov teeb meem uas EPS cov khoom tau yooj yim raug dej. Floating, qhov teeb meem ntawm loj txheej ntawm mortar. Nyob rau lub sijhawm no, thaum cov cement ntxiv thiab sib xyaw, cov pawg polar adsorbed rau ntawm qhov chaw ntawm EPS cov khoom sib cuam tshuam nrog cov cement hais thiab sib xyaw ua ke, kom cov haujlwm ntawm EPS rwb thaiv tsev mortar yog qhov zoo tuaj. Qhov no tau tshwm sim nyob rau hauv qhov tseeb tias EPS hais tau yooj yim wetted los ntawm cov cement paste, thiab lub zog sib txuas ntawm ob qho tib si tau txhim kho zoo heev.
Post lub sij hawm: Mar-14-2023