Preparation And Properties Of Thermal Insulation And Anticorrosive Coatings

In order to reduce the indoor temperature of oil tanks and buildings,coatings applied on outdoor surface are supposed to have outstanding thermal insulating properties.Pigments with low thermal conductivity and high reflectance,such as hollow glass microsphere(HGM),silicon aerogel(AG)and titanium dioxide are widely used in thermal insulating coatings.The anticorrosive properties should also be taken into consideration as exterior coatings are directly exposed to the sun and rain.Furthermore,with increasing awareness of environmental protection,waterborne coatings with low volatile organic pounds are widely used.Thus,preparing thermal insulating coatings with high thermal insulation properties and anticorrosive properties is of great importance.In this work,thermal insulating coatings were prepared using titanium dioxide,hollow glass microsphere and silicon aerogel as fillers and FEVE emulsion as binder.The recipe and preparation methods were discussed.The solar reflectance and temperature difference were measured to describe thermal insulating properties.The effect of different fillers,particle size,filler content and two-layer coatings were discussed.In addition,anticorrosive properties such as salt fog resistance and artificial accelerated weathering were also tested.Hollow glass microsphere with a diameter of 40 ?m showed better thermal insulating properties.The reflectance decreased and the temperature difference increased when the content of hollow glass microsphere increased.The optimum content of hollow glass microsphere ranged from 8 wt%-12 wt%.The reflectance decreased when the content of silicon aerogel increased,but the temperature difference decreased first,and then increased.The optimum content of silicon aerogel ranged from 1 wt% to 3wt%.The reflectance and temperature difference increased as the dry thickness increased.When the dry thickness increased up to 100 ?m,this trend became less obvious.When a top layer using only titanium dioxide as filler was applied on the HGM/AG layer,the thermal insulating properties were better.A top layer of 25 ?m and second layer of 100 ?m showed best insulating properties.When the content of hollow glass microsphere ranged from 8 wt% to 12 wt% and the content of silicon aerogel ranged from 1 wt% to 3 wt%,the coating showed proper anticorrosive properties and ageing resistance,which was competent for exterior coatings.