Product application in the industry

Three major functions determine the good status of fumed silica in super insulation materials

Thermal insulation materials refer to materials that can block the transfer of heat flow, also known as thermal insulation materials. Super insulating material refers to the insulating material whose thermal conductivity is lower than the thermal conductivity of "no convection air" under the intended use conditions.

At present, there are two main types of super insulation materials: one is vacuum insulation material, and the other is nanoporous insulation material. Fumed silica can exert its application and function in both superinsulation materials.

So how does fumed silica work in superinsulation?

Fumed silica is very suitable for the preparation of vacuum superinsulation materials and nanoporous superinsulation materials, because it has the characteristics required for the preparation of these two kinds of superinsulation materials.

First, its particle size is relatively small, the primary particle size is only 7-40nm, and the specific surface area is high, which can reach 400㎡/g, so the pores in its aggregates and examples are very small, and the porosity is relatively high.

Second, the morphology of fumed silica is a three-dimensional dendritic rigid silica aggregate formed by the fusion of primary silica particles, and then the aggregates are connected by hydrogen bonds and van der Waals forces to form silica agglomerates , so it has a smaller bulk density.

Third, it is prepared at high temperature (1200℃-2100℃), so it is relatively stable at high temperature. Finally, the molding process is convenient, and it can be directly mixed with other additives such as infrared shielding agent and enhancer for molding.

For a long time, due to the small scale of production of super insulation materials and the high cost of production, this material can only be used in military, aerospace and other fields. With the improvement of environmental protection and energy saving requirements, the energy crisis Intensified and with the decline of the production cost of fumed silica and the improvement of production technology, the application of fumed silica in super insulation materials will also become more and more extensive, and super insulation materials will also be further developed, and its application The field will also expand a lot.