Cov nyhuv ntawm Redispersible Emulsion Powder ntawm Slurry Structure

Redispersible latex hmoov yog cov khoom siv feem ntau siv cov organic gelling tau los ntawm cov tshuaj tsuag kom qhuav cov polymer emulsion nrog polyvinyl cawv raws li kev tiv thaiv colloid. Nws tuaj yeem rov ua kom sib npaug sib npaug hauv dej los tsim ib qho emulsion thaum nws ntsib dej. Ntxiv redispersible latex hmoov tuaj yeem txhim kho kev ua haujlwm ntawm cov cement mortar tshiab.

Sai li cov khoom siv cement-based ntxiv nrog latex hmoov hu rau dej, cov tshuaj tiv thaiv hydration pib, thiab cov tshuaj calcium hydroxide sai sai mus txog saturation thiab crystals yog precipitated, thiab tib lub sij hawm, ettringite crystals thiab calcium silicate hydrate gels yog tsim. Cov khoom siv tau muab tso rau ntawm cov gel thiab cov cement uas tsis muaj dej. Raws li cov tshuaj tiv thaiv hydr Lub aggregated polymer hais maj mam sau lub pores, tab sis tsis tag rau sab hauv ntawm lub pores. Raws li cov dej tau txo qis los ntawm kev ua dej los yog ziab, cov khoom sib txuas sib txuas ntawm cov gel thiab hauv cov pores coalesce rau hauv cov yeeb yaj kiab tas mus li, ua ib qho sib xyaw sib xyaw nrog cov hydrated cement paste thiab txhim kho hydration Bonding ntawm cov khoom thiab aggregates.

Vim hais tias cov khoom hydration nrog polymers tsim ib txheej txheej ntawm lub interface, nws yuav cuam tshuam rau kev loj hlob ntawm ettringite thiab ntxhib calcium hydroxide crystals; thiab vim hais tias cov polymers condense rau hauv cov yeeb yaj duab nyob rau hauv lub qhov hws ntawm lub interface hloov chaw, cov ntaub ntawv polymer cement-raws li kev hloov chaw yog denser. Cov pab pawg nquag hauv qee cov polymer molecules tseem yuav tsim cov kev sib txuas sib txuas nrog Ca2+ thiab A13+ hauv cov khoom siv cement hydration los tsim cov choj tshwj xeeb, txhim kho lub cev ntawm cov khoom siv cement-based hardened, txo cov kev ntxhov siab sab hauv, thiab txo cov tiam ntawm microcracks.

Raws li cov cement gel qauv tsim, cov dej tau noj thiab cov khoom polymer yog maj mam kaw hauv qhov pores. Raws li cov cement yog ntxiv hydrated, cov dej noo nyob rau hauv lub capillary pores txo, thiab cov polymer hais aggregate nyob rau saum npoo ntawm cov cement hydration khoom gel / unhydrated cement particle sib tov thiab cov aggregate, yog li tsim ib tug nruam kaw-packed txheej nrog loj pores puv. nrog nplaum los yog nws tus kheej-adhesive polymer hais.

Lub dispersed emulsion ntawm redispersible latex hmoov tuaj yeem tsim cov dej-insoluble nruam zaj duab xis (polymer network lub cev) tom qab ziab, thiab qhov qis elastic modulus polymer network lub cev tuaj yeem txhim kho kev ua haujlwm ntawm cov cement; Nyob rau tib lub sij hawm, nyob rau hauv lub polymer molecule Tej pawg polar nyob rau hauv cov cement reacts chemically nrog cov cement hydration khoom los tsim tshwj xeeb txuas hniav, txhim kho lub cev qauv ntawm cov cement hydration khoom, thiab alleviate thiab txo cov tiam ntawm cov kab nrib pleb. Tom qab ntxiv cov hmoov latex redispersible, qhov pib hydration ntawm cov cement qeeb qeeb, thiab cov yeeb yaj kiab polymer tuaj yeem qhwv ib nrab los yog tag nrho cov cement hais, kom cov cement tuaj yeem ua kom muaj dej txaus thiab nws cov khoom muaj zog tuaj yeem txhim kho.