Metals include ferrous metals (such as steel) and non-ferrous metals (such as aluminum alloys). In order to prevent rust, they must be surface treated. There are many surface treatment methods, of which cathodic protection surface treatment is a commonly used method. In the cathodic protection process, a zinc-rich primer is used. Zinc powder is a chemically active raw material. The electrode potential of zinc is 0.7628V and the electrode potential of iron is 0.409V. In the paint film, the zinc powder is in contact with each other and contacts with steel to conduct electricity. Therefore, when the steel structure coated with zinc-rich primer is corroded, because the electrode potential of metal zinc is lower than that of iron in a wide temperature range, zinc is the anode, which is corroded, iron is the cathode, which is protected and acts as a sacrificial anode Cathodic protection. At the same time, the product of zinc powder corrosion can fill the pores of the coating film, seal the damaged part of the coating film, and play a role of shielding the corrosion medium. Therefore, although the coating of zinc-rich paint is relatively thin, it still has a good anti-rust effect and a long service life.

Zinc-rich primers often use organic resins such as epoxy resins, chlorinated rubbers, vinyl resins, and polyurethanes as the film-forming binder. As early as 1962, it was discovered that zinc-rich primers formulated with partial hydrolysates of alkoxysilanes (such as ethyl orthosilicate) or alkali metal silicates and zinc powders were formulated to provide ferrous substrates. Cathodic protection is better than organic resin-based zinc-rich primer. However, the shortcomings of this technology are the short shelf life and the useful life of the paint. Twelve years later, it has been found that the stability and overall performance of the resulting zinc-rich primer are greatly improved by the transesterification reaction between silicate and organic polyols such as ethylene glycol or glycerol. This innovation was one of the most widely cited inventions of silicones from 1964 to 1985 and was cited 34 times. Because this zinc-rich primer introduces Si-O bond polymer, it has good corrosion resistance and adhesion; excellent weather resistance and heat resistance.