Preparation And Characterization Of Silica Thermal Insulation Coatings

In this paper,the composite thermal insulation coating of silica microspheres and airgel was designed and fabricated for the development and application of high performance thermal insulation coatings for heavy oil exploitation.Firstly,hollow silica microspheres and silica airgel powder insulation filler were prepared by hard template method and sol-gel method respectively.Then,the composite silica microspheres and the silica airgel powder were used as the coating,and the epoxy resin modified silicone resin was used as the film-forming agent.The insulating coating was prepared and the products under different processes The morphological characterization was carried out.The thermal insulation properties of the prepared thermal insulation coating were measured,and the influence of the process parameters on the thermal insulation performance was analyzed.The results show that the particle size of silica microspheres decreases with the increase of reaction temperature,and increases with the increase of volume fraction and ph value of tetraethyl silicate.Calcination temperature selection 400-500 ? range is more appropriate.Thermal insulation properties have shown that increasing the volume fraction of silica microspheres and airgel will reduce the thermal conductivity of the insulating coating.The thermal conductivity of the composite insulation coating using silica microspheres and silica aerogels is further reduced under appropriate proportions.Increasing the number of times the paint is applied will slightly enhance the insulation effect.At the same time,the thermal insulation effect of the coating increases with the increase of the amount of solvent,but too high solvent content will lead to cracking of the coating during heating.In this paper,the optimum conditions were as follows: the reaction temperature was 50 ?,the volume fraction of ethyl orthosilicate was 5%,the ph value was 10 and the calcination temperature was 450 ?.Diameter of 150 nm,microsphere thermal conductivity of 0.0356 W /(m · k),the prepared airgel powder thermal conductivity of 0.0237 W /(m · k),the use of both to prepare insulation coating with excellent insulation effect and Good workability and thermal stability.