Study On Preparation And Performance Of Epoxy Based Waterproof And Anticorrosive Coatings For Concrete

Concrete often causes structural failure due to insufficient durability.Concrete structural damage occurs in various projects such as infrastructure,roads and bridges,oceans,etc.,which brings huge losses to our country’s economy and threatens the safety of people’s lives.Therefore,the durability of concrete is improved.It is of great significance.Applying an effective protective coating on the surface of concrete can form a barrier on its surface to resist external environmental erosion.Epoxy-based coatings have attracted much attention due to their excellent performance.This article prepared a toughened ring based on the existing problems of epoxy coatings.Epoxy-based waterproof and anticorrosive coatings and infiltrated and consolidated epoxy-based waterproof and anticorrosive coatings.The basic physical properties,mechanical properties,consolidation capabilities,permeability,and water-and corrosion-resistant properties have been studied.After comprehensive analysis,the composition of each component has been determined.The optimal dosage,the experimental results are as follows:Through the method of controlling single factor variables,changing the addition amount of curing agent and cardanol to study the effect on coating performance.The solid content can reach up to 87.4%at the dosage of 1.8phr.The surface dry time of the sample at the dosage of2.0phr is only 20min.The tensile strength can reach up to 56.53Mpa at the dosage of 1.5phr.The elongation at break and impact strength are both at 1.8phr.The maximum amount is 10.7%and 10.33 k J/m~2 respectively.The sample with 1.5phr amount has the highest bond strength and bond strength retention rate,and the bonding performance is better.When 1.8phr amount is used,the lowest water absorption rate is 2.12%,and the coating is alkali resistant.It has better salt resistance performance.The acid resistance is the best when the amount of 1.8phr is used.In summary,the best use amount of the curing agent should be between 1.5phr-1.8phr.The tensile strength of the sample gradually decreases after cardanol is added,and when the cardanol added amount is 15%,the elongation at break and impact strength reach the maximum value of 17.6%and 13.71 k J/m~2.The bond strength and bond strength retention rate both reach the maximum when the amount of cardanol is 15%,and the water absorption rate is at the amount of cardanol.When it is 15%,it reaches the minimum value of 1.57%.The alkali resistance and salt resistance of the coating are good.The two groups of samples with 12%and15%cardanol have the best acid resistance.In summary,the addition of cardanol The amount should be controlled between 12%-15%.The reaction feasibility of the infiltrated and consolidated epoxy-based waterproof and anticorrosive coating was analyzed,and methyl ethyl ketone was selected as the solvent to prepare the infiltrated and consolidated epoxy-based waterproof and anticorrosive coating.The effects of different solvent additions,aldol condensation reaction between solvents and different glycidyl ether additions on coating performance were studied.With the gradual increase in the amount of solvent added,the solid content of the coating gradually decreases,the initial viscosity gradually decreases,and the surface drying time becomes longer.The sample with 80%solvent content has the best penetration performance on the concrete surface,and the maximum penetration depth is 6.0mm;the maximum adhesive strength of the sample with 60%solvent addition on the dry base surface and the wet base surface is 6.1Mpa and 5.1Mpa,and the water absorption rate reaches the minimum 1.47%.The aldol condensation reaction between the solvents the coating is modified.As the proportion of ketone compounds increases,the solid content of the sample gradually increases,and the initial viscosity increases but the surface drying time becomes longer;the penetration depth on the concrete surface decreases,and the permeability is basically lost.The bonding strength between the base surface and the wet base surface has been improved,and the water absorption rate gradually increased;after adding glycidyl ether,the solid content of the coating gradually increased and both were greater than80%,up to 91.3%,and the initial viscosity gradually increased.The drying time is gradually shortened,and the mechanical properties of the samples are gradually enhanced;the permeability on the concrete surface becomes worse;the bonding strength between the dry base and the wet base is gradually reduced;the water absorption rate of the sample with 20%glycidol is the smallest 1.22%;the alkali resistance and salt resistance of each group of samples are good,there is no blistering or shedding after soaking for 28 days,the sample with the worst acid resistance has blistering in the coating at 9 days,and the acid resistance is the best The sample blistered at 21d.