polymer foda da sauran inorganic adhesives (kamar sumunti, slaked lemun tsami, gypsum, yumbu, da dai sauransu) da kuma daban-daban aggregates, fillers da sauran Additives [kamar hydroxypropyl methylcellulose, polysaccharide (sitaci ether), fiber Fiber, da dai sauransu] suna jiki gauraye don yin busasshen turmi. Lokacin da aka ƙara busassun busassun turmi a cikin ruwa kuma a motsa, a ƙarƙashin aikin hydrophilic colloid mai kariya da ƙarfin jujjuyawar injiniya, za a iya watsar da ƙwayoyin latex foda cikin sauri cikin ruwa, wanda ya isa ya sanya foda mai sakewa da cikakken fim. A abun da ke ciki na roba foda ne daban-daban, wanda yana da wani tasiri a kan rheology na turmi da daban-daban gina Properties: da dangantaka da latex foda ga ruwa a lõkacin da aka redispersed, daban-daban danko na latex foda bayan watsawa, da sakamako a kan iska abun ciki na turmi da kuma rarraba kumfa, The hulda tsakanin roba foda da kuma sauran Additives da karuwa da ruwa ayyuka, da yawa latex foda, da karuwa da latex foda. danko.
An yi imani da cewa tsarin da redispersible latex foda inganta workability na sabo turmi shi ne cewa latex foda, musamman m colloid, yana da dangantaka da ruwa a lokacin da tarwatsa, wanda qara danko na slurry da kuma inganta cohesion na ginin turmi.
Bayan da sabon turmi mai dauke da latex foda watsawa aka samu, tare da sha da ruwa ta tushe saman, da amfani da hydration dauki, da volatilization zuwa iska, ruwa a hankali raguwa, da guduro barbashi sannu a hankali gabatowa, da interface a hankali blurs, da guduro a hankali fuses da juna. ƙarshe polymerized a cikin wani fim. Tsarin samar da fim ɗin polymer ya kasu kashi uku. A cikin mataki na farko, ƙwayoyin polymer suna motsawa cikin yardar kaina a cikin nau'i na motsi na Brownian a farkon emulsion. Yayin da ruwa ke ƙafewa, motsin ɓangarorin a zahiri yana ƙara ƙuntatawa, kuma tashin hankali tsakanin ruwa da iska yana sa su daidaita a hankali tare. A mataki na biyu, lokacin da barbashi suka fara tuntuɓar juna, ruwan da ke cikin hanyar sadarwa yana ƙafewa ta cikin capillary, kuma matsanancin tashin hankali da ake yi a saman ɓangarorin yana haifar da nakasawa na latex spheres ya sa su haɗu tare, sauran ruwan ya cika pores, kuma fim ɗin ya zama kusan kafa. Mataki na uku da na ƙarshe yana ba da damar watsawa (wani lokaci ana kiran kai-mannewa) na ƙwayoyin polymer don samar da fim mai ci gaba da gaske. A lokacin ƙirƙirar fim, keɓaɓɓen barbashi na latex na wayar hannu suna haɓaka zuwa wani sabon yanayin fim na bakin ciki tare da matsanancin damuwa. Babu shakka, domin foda mai tarwatsewa ta polymer ya sami damar samar da fim a cikin turmi da aka sake tadawa, dole ne a tabbatar da mafi ƙarancin zafin jiki na fim (MFT) ya zama ƙasa da yanayin zafin turmi.
Colloid - polyvinyl barasa dole ne a rabu da tsarin membrane na polymer. Wannan ba matsala ba ne a cikin tsarin turmi na simintin alkaline, saboda polyvinyl barasa za a saponified ta alkali samar da siminti hydration, da adsorption na quartz abu zai sannu a hankali raba polyvinyl barasa daga tsarin, ba tare da hydrophilic colloid kariya. , Fim ɗin da aka kafa ta hanyar watsar da foda mai lalacewa, wanda ba shi da ruwa a cikin ruwa, ba zai iya aiki kawai a cikin yanayin bushe ba, har ma a cikin yanayin nutsewar ruwa na dogon lokaci. Hakika, a cikin wadanda ba alkaline tsarin, irin su gypsum ko tsarin da kawai fillers, tun da polyvinyl barasa har yanzu partially wanzu a karshe polymer film, wanda rinjayar da ruwa juriya na fim, a lokacin da wadannan tsarin ba a yi amfani da dogon lokacin da ruwa nutsewa , da kuma polymer har yanzu yana da halayyar inji Properties, dispersible polymer foda har yanzu za a iya amfani da a cikin wadannan tsarin.
Tare da samuwar karshe na fim ɗin polymer, an kafa tsarin da ya ƙunshi inorganic da masu ɗaure a cikin turmi da aka warke, wato, kwarangwal da kwarangwal mai ƙarfi wanda ya ƙunshi kayan hydraulic, kuma foda polymer mai redispersible an kafa a cikin rata da m surface. m cibiyar sadarwa. Ƙarfin ƙarfi da haɗin kai na fim ɗin resin polymer wanda aka kafa ta latex foda yana haɓaka. Saboda sassauci na polymer, ƙarfin nakasar ya fi girma fiye da tsayayyen tsarin dutsen siminti, aikin nakasar turmi yana inganta, kuma tasirin tarwatsa damuwa yana inganta sosai, don haka inganta juriya na turmi.
Tare da haɓaka abun ciki na foda polymer mai tarwatsewa, duk tsarin yana tasowa zuwa filastik. A cikin hali na babban abun ciki na latex foda, da polymer lokaci a cikin warke turmi sannu a hankali ya wuce inorganic hydration samfurin lokaci, turmi zai sha qualitative canje-canje da kuma zama wani elastomer, da hydration samfurin na ciminti zai zama "filler" "The tensile ƙarfi, elasticity, sassauci da sealing Properties na mortard polymer foda an inganta dispersible polymer foda. foda yana ba da damar fim ɗin polymer (fim ɗin latex) don samar da wani ɓangare na bangon pore, ta haka ne ke rufe tsarin turmi mai ƙarfi na latex membrane yana da tsarin daidaita kansa wanda ke amfani da tashin hankali zuwa turmi ta hanyar waɗannan runduna ta ciki gabaɗaya, ta haka ne ke haɓaka ƙarfin haɗin gwiwa da haɓakar ƙwanƙwasa na turmi. Tsarin don haɓaka yawan damuwa da rashin ƙarfi shine kamar haka: lokacin da aka yi amfani da karfi, ana jinkirta microcracks saboda haɓakawa da sassauci, kuma kada ku kasance har sai an kai ga matsananciyar damuwa. Bugu da ƙari, yankunan polymer ɗin da aka haɗa su kuma suna hana haɗakar microcracks zuwa cikin fashe-fashe. Sabili da haka, foda na polymer mai tarwatsewa yana ƙaruwa da rashin ƙarfi da rashin ƙarfi na kayan.
Fim ɗin polymer a cikin turmi mai gyare-gyare na polymer yana da tasiri mai mahimmanci akan taurin turmi. Rubutun polymer foda wanda za'a iya rarrabawa a kan mahaɗin yana taka muhimmiyar rawa bayan an tarwatsa kuma an kafa shi a cikin fim, wanda shine ƙara haɓakawa ga kayan da aka haɗa. A cikin microstructure na wurin mu'amala tsakanin foda-polymer-gyara yumbu tayal bonding turmi da yumbu tile, fim din da polymer kafa gada tsakanin vitrified yumbu tile tare da matsananci low ruwa sha da siminti turmi matrix. Yankin tuntuɓar tsakanin abubuwa guda biyu masu ban sha'awa wuri ne na musamman mai haɗari inda raguwar raguwa ke haifar da haifar da asarar mannewa. Saboda haka, ikon fina-finai na latex don warkar da raguwar raguwa yana taka muhimmiyar rawa a cikin tile adhesives.
A lokaci guda kuma, foda mai yuwuwar yuwuwar yumbu mai ɗauke da ethylene yana da fitattun mannewa ga abubuwan halitta, musamman makamantansu, irin su polyvinyl chloride da polystyrene. Kyakkyawan misali na
Lokacin aikawa: Oktoba-31-2022