Silicones have low surface tension & therefore they can spread & get into the pores of the surface easily.The water repellant methyle group is directed towards the surface by the siloxanes, creating a breathable cover which allows the internal vapours trapped in the substrate but does not allow external water to enter.The advantages are as follows:
The ability to thoroughly cover a surface or penetrate a porous substrate Permeability to water vapour, Resistance to ultraviolet rays, heat, and oxidative degeneration Durability, flexibility, and mechanical and chemical adhesion.