Study On Modified Polymer Cement Waterproof Mortar

The rapid development of China's national economy has promoted the vigorous development of infrastructure construction and urban construction.However,many problems have been exposed in terms of project quality,especially in terms of project leakage.The leakage of the project is mainly caused by the poor quality of the waterproof construction of the project.The quality of the waterproof project is mainly determined by the waterproof material and the construction.In recent years,polymer cement waterproof mortar is widely used in building waterproof engineering due to its good impermeability,crack resistance and durability.There are many varieties of polymer cement waterproof mortar,and the quality is uneven.In this paper,the effects of various components of the polymer cement waterproof mortar on its performance are systematically studied.On this basis,a polymer cement waterproof mortar with good mechanical properties,crack resistance,impermeability and durability is prepared by modifying the polymer waterproof cement mortar with attapulgite and metakaolin.The research results are as follows:1.The effects of different components on the performance of polymer cement waterproof mortar were studied,and the mechanical properties,drying shrinkage properties,adhesive properties,water absorption and impermeability properties of the mortar were studied.The research results show that in the three polymer powders of ethylene-vinyl acetate copolymer?EVA?,styrene-acrylate copolymer?SAE?and butadiene-styrene latex copolymer?SBR?,the styrene-acrylic acid Ester copolymer?SAE?is more suitable for polymer cement waterproof mortar,the best effect is achieved when its content is controlled at about 8%;three mineral admixtures of fly ash,silica fume and ore powder have a significant impact on the performance of polymer cement waterproof mortar,and the best result is obtained by respectively adding 10%fly ash,5%silica fume and 5%ore powder.The effects of three additives such as defoamer,expansive agent and water repellent on the performance of polymer cement waterproof mortar are also significant.The best effect is obtained when the amount of antifoaming agent is 0.3%,the amount of expansion agent is0.9%and the amount of waterproofing agent is 9%.2.The effects of 400 mesh,800 mesh,1250 mesh,and 1500 mesh calcined attapulgite on the performance of polymer cement waterproof mortar were studied.After calcining at high temperature,the attapulgite has collapsed and destroyed its lattice,generating a large amount of active Si O₂And active Al₂O₃vitreous substances,which have good pozzolanic activity.These substances and Ca?OH?₂in cement hydration products generate hydrated calcium silicate and hydrated calcium aluminate.The experimental results show that 1250 mesh attapulgite with the best content of about 10%can greatly improve the performance of mortar impermeability,frost resistance,sulfate resistance,etc.;The joint agent?KH?modifies the attapulgite.The surfactant SA binds to the attapulgite surface and introduces hydrophobic groups,thereby releasing the water absorbed by the attapulgite.The silane coupling agent KH chemically bonds on the surface of the attapulgite and grafts on the surface of the attapulgite to improve the surface structure of the attapulgite.The modified attapulgite has better performance by adding mortar,and the modified attapulgite is better when 0.4%surfactant SA and 6%silane coupling agent HK were combined.3.The effect of calcined metakaolin with four finenesses of 400 mesh,800mesh,1250 mesh and 1500 mesh on the performance of polymer cement waterproof mortar was studied.Metakaolin possesses pozzolanic activity,and its activated aluminum and activated silicon can be hydrated with cement Ca?OH?₂reacts to form gel materials such as CSH and CASH,promote cement hydration,refine the pore structure and reduce porosity.The experimental results show that when the amount of 1250 mesh metakaolin is about 15%,the effect is the best.Significantly improve the performance of mortar impermeability,frost resistance,resistance to sulfate corrosion,etc.;then use surface active agent?SA?and silane coupling agent?KH?to modify metakaolin,surfactant SA and Ca⁺reaction The insoluble calcium salt fills the pores of the mortar.The silane coupling agent is grafted on the surface of metakaolin,which improves the activity of metakaolin.At the same time,the hydrophilicity of the silane coupling agent accelerates the rate of secondary hydration reaction.The modified metakaolin is better in adding mortar,and metakaolin modified by 0.4%surfactant SA and 6%silane coupling agent KH has better effect.