Cov hmoov emulsion thiab cov hmoov latex redispersible tuaj yeem tsim lub zog tensile siab thiab lub zog sib txuas ntawm cov ntaub ntawv sib txawv tom qab tsim zaj duab xis, lawv siv ua tus binder thib ob hauv mortar los sib xyaw nrog cov inorganic binder cement, cement thiab polymer feem. Muab kev ua si tag nrho rau cov zog sib xws los txhim kho kev ua tau zoo ntawm mortar.
Los ntawm kev soj ntsuam cov qauv me me ntawm cov khoom siv polymer-cement sib xyaw, nws ntseeg tau tias qhov ntxiv ntawm cov hmoov latex redispersible tuaj yeem ua rau cov polymer tsim ib zaj duab xis thiab dhau los ua ib feem ntawm phab ntsa qhov, thiab ua rau cov mortar tsim ib qho tag nrho los ntawm lub zog sab hauv, uas txhim kho lub zog sab hauv ntawm cov mortar. Lub zog polymer, yog li txhim kho qhov kev ntxhov siab ntawm cov mortar thiab ua rau muaj kev ntxhov siab kawg.
Lub microstructure ntawm cov polymer hauv cov mortar tsis tau hloov pauv ntev, thiab nws tswj kev sib txuas ruaj khov, flexural thiab compressive zog, thiab hydrophobicity zoo. Lub mechanism tsim ntawm redispersible latex hmoov ntawm lub zog ntawm cov vuas nplaum pom tias tom qab polymer qhuav rau hauv ib zaj duab xis, cov zaj duab xis polymer tsim kev sib txuas yooj ywm ntawm cov mortar thiab cov vuas ntawm ib sab tes, thiab ntawm qhov tod tes, cov polymer hauv cov mortar tshiab Ua kom cov pa ntawm cov mortar thiab cuam tshuam rau kev tsim thiab wettability ntawm qhov chaw, thiab tom qab ntawd thaum lub sijhawm teeb tsa, cov polymer kuj muaj kev cuam tshuam zoo dua rau cov txheej txheem hydration thiab shrinkage ntawm cov cement hauv cov binder, uas yuav pab txhawb rau kev txhim kho lub zog Bond muaj kev pab zoo dua.
Ntxiv cov hmoov latex uas tawg tau dua rau hauv cov mortar tuaj yeem txhim kho lub zog sib txuas nrog lwm cov ntaub ntawv, vim tias cov hmoov latex hydrophilic thiab cov kua dej ntawm cov cement suspension nkag mus rau hauv cov qhov hws thiab cov hlab ntsha ntawm lub matrix, thiab cov hmoov latex nkag mus rau hauv cov qhov hws thiab cov hlab ntsha. Cov zaj duab xis sab hauv yog tsim thiab nqus tau zoo rau ntawm qhov chaw ntawm lub substrate, yog li ua kom muaj lub zog sib txuas zoo ntawm cov khoom siv cementitious thiab lub substrate.
Qhov kev ua kom zoo dua ntawm cov hmoov latex rau kev ua haujlwm ntawm cov mortar yog vim qhov tseeb tias cov hmoov latex yog cov polymer molecular siab nrog cov pawg polar. Thaum cov hmoov latex sib xyaw nrog cov khoom EPS, qhov tsis yog-polar hauv cov saw hlau tseem ceeb ntawm cov hmoov latex polymer yuav muaj kev nqus dej lub cev nrog rau qhov tsis yog-polar ntawm EPS. Cov pawg polar hauv cov polymer tau taw qhia sab nraud ntawm qhov chaw ntawm cov khoom EPS, yog li cov khoom EPS hloov pauv ntawm hydrophobicity mus rau hydrophilicity. Vim yog kev hloov pauv ntawm qhov chaw ntawm cov khoom EPS los ntawm cov hmoov latex, nws daws qhov teeb meem uas cov khoom EPS yooj yim raug dej. Floating, qhov teeb meem ntawm cov txheej loj ntawm mortar. Lub sijhawm no, thaum cement ntxiv thiab sib xyaw, cov pawg polar adsorbed ntawm qhov chaw ntawm cov khoom EPS cuam tshuam nrog cov khoom cement thiab sib xyaw ua ke, yog li qhov ua haujlwm ntawm EPS rwb thaiv tsev mortar tau zoo dua. Qhov no yog qhov cuam tshuam hauv qhov tseeb tias cov khoom EPS tau yooj yim ntub los ntawm cov cement paste, thiab lub zog sib txuas ntawm ob qho tau zoo dua.
Lub sijhawm tshaj tawm: Lub Peb Hlis-18-2023