Rubutun polymer foda da sauran adhesives na inorganic (kamar sumunti, lemun tsami, gypsum, yumbu, da dai sauransu) da kuma nau'o'i daban-daban, masu cikawa da sauran addittu [irin su hydroxypropyl methylcellulose, polysaccharide (sitaci ether), fiber Fiber, da dai sauransu] suna cikin jiki. gauraye domin yin busasshen turmi mai gauraya. 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 tasiri a kan rheology na turmi da kuma daban-daban gina Properties: da zumunta na latex foda ga ruwa a lõkacin da aka redispersed, daban-daban danko na latex foda bayan watsawa, da tasiri a kan Abubuwan da ke cikin iska na turmi da rarraba kumfa, Haɗin kai tsakanin foda foda da sauran additives yana sa nau'ikan latex daban-daban suna da ayyuka na ƙara yawan ruwa, ƙara thixotropy, da karuwa. 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 inganta cohesion na turmi gini.
Bayan sabon turmi da ke ɗauke da ɗimbin foda mai tarwatsewa ya samu, tare da shayar da ruwa ta gindin tushe, da shan hydration dauki, da kuma jujjuyawar iska, ruwa a hankali yana raguwa, ƙwayoyin guduro a hankali suna gabatowa, haɗin gwiwar a hankali ya blurs. , kuma guduro a hankali yana haɗuwa da juna. ƙarshe polymerized a cikin wani fim. An raba tsarin samar da fim ɗin polymer zuwa matakai uku. A 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 sassan sassan jikin yana haifar da nakasawa na latex spheres ya sa su hade tare, kuma. sauran ruwan ya cika pores, kuma fim ɗin yana da ƙima. 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 tsarin turmi na simintin alkaline, saboda polyvinyl barasa za a saponified ta alkali da aka samar ta hanyar siminti hydration, da adsorption na quartz abu zai rabu da polyvinyl barasa a hankali 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. Tabbas, a cikin tsarin da ba na alkaline ba, irin su gypsum ko tsarin tare da masu cikawa kawai, tun da polyvinyl barasa har yanzu yana wanzu a cikin fim ɗin polymer na ƙarshe, wanda ke shafar juriya na ruwa na fim, lokacin da ba a yi amfani da waɗannan tsarin don ruwa na dogon lokaci ba. nutsewa , da kuma polymer har yanzu yana da halayyar inji Properties, dispersible polymer foda za a iya amfani da har yanzu 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 sassaucin ra'ayi 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 karuwar 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 kuma ya zama elastomer, da hydration samfurin na ciminti zai zama "filler" ". Ƙarfin ƙwanƙwasa, elasticity, sassauci da kaddarorin rufewa na turmi da aka gyara tare da rarrabuwar foda polymer. Haɗin foda na polymer mai tarwatsewa yana ba da damar fim ɗin polymer (fim ɗin latex) don samar da kuma samar da wani ɓangare na bangon ramukan, ta haka ne ke rufe tsarin turmi mai ƙarfi sosai. Membran latex yana da tsarin mikewa da kansa wanda ke amfani da tashin hankali ga angarinsa da turmi. Ta hanyar waɗannan dakarun cikin gida, ana riƙe turmi gaba ɗaya, ta haka ne ke ƙara ƙarfin haɗin kai na turmi. Kasancewar ƙwaƙƙwarar ƙwaƙƙwarar ƙira da ƙima sosai yana inganta haɓaka da haɓakar turmi. Hanyar haɓakar haɓakar haɓakar haɓakar haɓaka da ƙarfin gazawar ita ce kamar haka: lokacin da aka yi amfani da ƙarfi, ana jinkirta microcracks saboda haɓakar haɓakawa da haɓakawa, kuma kada ku samar har sai an sami 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 damuwa na 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