Cellulose ether zai jinkirta hydration na siminti zuwa daban-daban digiri, wanda aka bayyana a jinkirta samuwar ettringite, CSH gel da calcium hydroxide.A halin yanzu, hanyar cellulose ether jinkirta ciminti hydration yafi hada da zato na hana ion motsi, alkali lalata da adsorption.
1. Hasashen hana motsin ion
An yi la'akari da cewa ethers cellulose yana ƙara danko na maganin pore, yana hana yawan motsi na ion, don haka jinkirta ciminti hydration.Duk da haka, a cikin wannan gwaji, ether cellulose tare da ƙananan danko yana da ƙarfin da ya fi ƙarfin jinkirta ciminti hydration, don haka wannan hasashe ba ya riƙe.A gaskiya ma, lokacin motsi ko ƙaura yana da ɗan gajeren lokaci, wanda ba zai iya kwatantawa da lokacin jinkirin ciminti ba.
2. Lalacewar alkaline
Polysaccharides sau da yawa ana sauƙaƙa ƙasƙanta a ƙarƙashin yanayin alkaline don samar da acid hydroxycarboxylic waɗanda ke jinkirta ruwan siminti.Saboda haka, dalilin da ya sa cellulose ether jinkirta ciminti hydration na iya zama cewa ya ƙasƙanta a cikin alkaline ciminti slurry don samar da hydroxycarboxylic acid, amma binciken ya gano cewa Cellulose ether ne sosai barga a karkashin alkaline yanayi, kawai dan kadan ƙasƙanci, da ƙasƙantar da kayayyakin da kusan babu wani tasiri. a kan jinkirta ciminti hydration.
3. Adsorption
Adsorption na iya zama ainihin dalilin da yasa cellulose ether ya jinkirta jinkirin ciminti.Yawancin abubuwan da suka hada da kwayoyin halitta za su shiga cikin siminti da samfuran hydration, suna hana rushewar simintin siminti da crystallization na samfuran hydration, don haka jinkirta hydration da saitin siminti.An gano cewa cellulose ether yana da sauƙin adsorbed zuwa calcium hydroxide, C. S.Fuskar samfuran hydration irin su H gel da calcium aluminate hydrate, amma ba abu ne mai sauƙi ba a haɗa su ta hanyar ettringite da lokacin rashin ruwa.Bugu da ƙari, dangane da ether cellulose, ƙarfin adsorption na HEC ya fi ƙarfin na MC, kuma ƙananan abun ciki na hydroxyethyl a cikin HEC ko hydroxypropyl a cikin HPMC, ƙarfin adsorption shine: dangane da samfurori na hydration, hydrogen. Ƙarfin adsorption na calcium oxide C.S.Ƙarfin adsorption na H ya fi karfi.Ƙarin bincike kuma ya nuna cewa ƙarfin adsorption na samfurori na hydration da cellulose ether yana da dangantaka mai dacewa tare da jinkirta ciminti hydration: da karfi da adsorption, da karin jinkirin jinkiri, amma adsorption na ettringite zuwa cellulose ether yana da rauni, amma samuwarsa. an jinkirta sosai.Har ila yau, binciken ya nuna cewa cellulose ether yana da tasiri mai karfi akan tricalcium silicate da samfurori na hydration, don haka yana jinkirta jinkirin lokacin silicate, kuma yana da ƙananan adsorption zuwa ettringite, amma an hana samuwar ettringite.Babu shakka jinkirta, wannan saboda jinkirta samuwar ettringite yana shafar ma'aunin Ca2 + a cikin maganin, wanda shine ci gaba da jinkirin silicate hydration na cellulose ether.
A cikin sakamakon gwajin, ƙarfin retarding na HEC ya fi ƙarfin na MC, kuma ikon cellulose ether don jinkirta samuwar calcium hydroxide ya fi ƙarfin C. S.Ƙarfin H gel da ettringite yana da ƙarfi, wanda ke da alaƙa mai dacewa tare da ƙarfin adsorption na ether cellulose da siminti hydration kayayyakin.An kara tabbatar da cewa adsorption na iya zama ainihin dalilin da ya sa ether cellulose ya jinkirta jinkirin siminti, kuma ether cellulose da simintin hydration samfurori suna da dangantaka mai dacewa.Ƙarfin ƙarfin adsorption na samfuran hydration na siminti, mafi ƙarancin samuwar samfuran hydration na jinkiri.Sakamakon gwajin da aka yi a baya ya nuna cewa ethers na cellulose daban-daban suna da tasiri daban-daban akan jinkirin jinkirin simintin siminti na Portland, kuma ether guda ɗaya yana da tasirin jinkiri daban-daban akan samfuran hydration daban-daban, wanda ke nuna cewa samfuran simintin simintin Portland suna da tasiri daban-daban akan fiber.Adsorption na ether cellulose shine zaɓi, kuma tallan ether na cellulose zuwa samfuran hydration na siminti shima zaɓi ne.
Lokacin aikawa: Fabrairu-27-2023