Study On Lithium Silicate Water-based Coating And High Temperature Resistant Coating

Water-based coating is used widely in construction,furniture,and other industries,which with non-toxic,harmless,non-combustible,etc.It is a typical representative of coatings,which toward the direction of development in green,environmental protection.The traditional water-based coating is not ideal in its performance that used in the furniture industry.It emphasizes the water resistance while ignoring the hardness,resistance to alcohol,alkali resistance and other properties.It is significant to ensure that water-based coating excellent water resistance while improving the hardness of water-based coating,as well as other properties.High temperature coating is functional coating used in high temperature environment.It is typical of the development of coatings toward the functional direction.At present,organic high temperature coating is the main part of high temperature resistant coating.Inorganic high temperature coating has gradually developed,with the changing of high temperature coating application environment and performance requirements.It is significant to research on high temperature coating with excellent performance.Lithium silicate aqueous solution is usually prepared by lithium salt and silicate solution,with good mechanical,physical and chemical stability,etc.It can be used as paint base,binder,surface treatment agent,and so on.The coating film of lithium silicate aqueous solution used in coatings is heat resistant,water resistant,self-dry,non-flammable,and so on.In this experiment,lithium silicate aqueous solution will be added to the water-based coating primer and water-based coating varnish for modification.The effect of multiple factors on the properties of the modified water-based coating will be discussed by single factor method.The orthogonal analysis method will be used to optimize the modification process.And the formula for the modification of water-based coating will be obtained.In the experiment of lithium silicate water-based coating primer,the optimum combination conditions are as follows: the concentration of lithium silicate is 20%,the lithium silicate modulus is 8,the amount of lithium silicate is 0.6g,the water glassconcentration is 22%,the amount of water glass is 0.08 g,combining with single factor experiments and orthogonal experimental results.The performance of lithium silicate water-based coating primer made in the best conditions are as follows:hardness is H,water resistance,resistance to alcohol and alkali resistance are 0,heat resistance is 190℃,apparent drying time is 53.3min,hard drying time is 3.5h,which better than the performance of the original water-based coating primer.XRD,scanning electron microscopy and TGA are used to characterize the test samples.The results showed that the performance of test samples are excellent.Through single factor experiment and orthogonal experiment,the optimum combination conditions in the experiment of lithium silicate water-based coating varnish are as follows: the lithium silicate concentration is 15%,the lithium silicate modulus is 8,the amount of lithium silicate is 0.3 g,the water glass concentration is18%,the amount of water glass is 0.14 g.The performance of lithium silicate water-based coating varnish made in the best conditions is better: hardness is H,water resistance,alkali resistance,resistance to alcohol and pollution resistance are 0,heat resistance is 210℃,apparent drying time is 35 min,hard drying time is 3h,which better than the performance of the original water-based coating varnish.XRD,scanning electron microscopy and TGA are used to characterize the test samples.The results showed that the performance of test samples are excellent.In the experiment of high temperature resistant coating,the optimum formula are as follows: kaolin is 2.5g,magnesium oxide is 0.5g,alumina is 1.0g,wollastonite is 0.5g,glass powder is 0.5g,water glass is 3.0g,lithium silicate aqueous solution is 1.0g,additive is 0.5 g.Through the verification experiment,the performance of the high temperature resistant coating prepared under the best formula are as follows:the drying time is 177 min,the heat resistance is 883.3 ℃.There is a certain insulation effect.The test samples are characterized by XRD,SEM and TGA analysis,and so on.The results showed that the performance of test samples are excellent.High temperature performance is excellent under 1000 ℃,with the loss rate of sample is about 6.67%.