Taw qhia rau RDP-Redispersible Polymer Powder

Redispersible polymer hmoov (RDP) yog cov hmoov polymer raws li siv hauv ntau daim ntawv thov hauv kev tsim kho kev lag luam. RDP tau txais los ntawm cov tshuaj tsuag kom qhuav ntawm polymer emulsions. Nws yog dav siv nyob rau hauv cement systems los txhim kho cov khoom ntawm mortars xws li adhesion, dej tsis kam thiab flexural zog.

RDP yog tsim los ntawm ntau yam polymers, xws li yas acetate-ethylene (VAE), styrene-butadiene (SB), ethylene-vinyl chloride (EVC), thiab polyvinyl cawv (PVA). Cov polymers no tau tsim los ua kom sib haum nrog ntau hom kev sib khi xws li cement, txiv qaub thiab gypsum. Lawv yog siv nyob rau hauv ntau hom kev siv nrog rau cov pobzeb nplaum, tus kheej-leveling tebchaw, waterproofing membranes thiab sab nrauv rwb thaiv tsev thiab xov tshuab (EIFS).

Cov txheej txheem tsim khoom ntawm RDP muaj peb theem tseem ceeb: polymerization, emulsification thiab tshuaj tsuag kom qhuav. Nyob rau hauv lub polymerization theem, monomers yog polymerized nyob rau hauv tej yam kev mob, xws li kub, siab thiab tshuaj tiv thaiv lub sij hawm. Lub resulting polymer dispersion yog stabilized nrog surfactants los tiv thaiv particle agglomeration. Nyob rau hauv lub emulsification theem, lub polymer dispersion yog ntxiv ua rau ib tug emulsion, uas yog ces tsuag qhuav kom tau RDP. Thaum lub sij hawm ziab qhuav, dej evaporates los ntawm cov emulsion droplets, tsim cov khoom polymer. Lub resulting hmoov yog ces sau thiab ntim rau shipping.

Cov khoom ntawm RDP nyob ntawm ntau yam xws li hom polymer, particle loj thiab tshuaj muaj pes tsawg leeg. Qhov feem ntau siv polymer rau RDP yog VAE, uas muaj cov nplaum zoo thiab dej tsis kam. Qhov luaj li cas ntawm RDP tuaj yeem sib txawv ntawm ob peb microns mus rau ob peb millimeters, nyob ntawm daim ntawv thov. Cov tshuaj muaj pes tsawg leeg ntawm RDP kuj tuaj yeem sib txawv raws li qhov xav tau. Piv txwv li, RDPs tuaj yeem muaj cov khoom siv ntxiv xws li plasticizers, dispersants thiab thickeners los txhim kho lawv cov khoom.

RDP muaj ntau yam zoo dua lwm hom polymers siv hauv kev tsim kho. Ib qho ntawm qhov zoo tshaj plaws yog nws lub peev xwm los hloov pauv hauv dej. Qhov no txhais tau hais tias RDP tuaj yeem sib xyaw nrog dej los tsim cov emulsion ruaj khov, uas tuaj yeem siv rau ntau yam kev siv. Lub redispersibility ntawm RDP nyob ntawm nws cov tshuaj muaj pes tsawg leeg thiab particle loj. RDP particles yog tsim los ua dej sib xws thiab tawg sai sai thaum sib xyaw nrog dej.

Lwm qhov zoo ntawm RDP yog nws lub peev xwm los txhim kho kev ua haujlwm ntawm cov cement systems. RDP tuaj yeem txhim kho qhov adhesion ntawm mortar thiab substrate, txo qhov shrinkage thiab nce lub zog ntawm mortar. Nws kuj tseem txhim kho cov dej tsis kam ntawm cov mortar, tiv thaiv cov dej nkag thiab txo qhov kev pheej hmoo ntawm huab cua.