Borates have been started to be used in various materials (wood, cellulosic insulation, PVC and textile) for flame retardant purposes. Boron suppresses combustion by covering the burning material in such a way that it stops contact with oxygen.
Zinc borate is used in plastic materials and soluble borates such as boric acid, borax pentahydrate and borax decahydrate are used in cellulosic materials. These materials are natural fibers such as wood, plywood, wood fiber, paper and cotton.
In cellulosic insulation, borax pentahydrate and boric acid are used. These products are used to increase energy efficiency, to prevent the growth of fungi and other microorganisms and to increase the resistance of the material against flame.
Boron compounds used in PVC as a flame retardant are mainly zinc borate, barium metaborate, boron phosphates and ammonium fluoborate. HCl is released while PVC is burning. When zinc borate is added as a flame retardant to PVC, this gas reacts with non-volatile zinc and boron compounds to prevent the release of harmful gases.
Although borax and boric acid are useful flame retardants in the textile field, the problem of washing away from the product may be encountered due to their water solubility.
Disodium octaborate tetrahydrate can be successfully used for long-term protection of wood from fungi and insects. This material can be applied very easily to the timber by spraying, painting or pressure without any special precautions.