| abstract |
Certain phosphonic acid salts heated at temperatures over 200° C. generate thermally stable, highly efficient flame retardant materials well suited for use as flame retardant additives in polymers. Various methods for preparing flame retardant materials from more than one phosphonic acid salts are provided, wherein each method can generate different flame retardant materials from the same mixture of starting phosphonic acids. The flame retardants of the invention can be used as the sole flame retardant in a composition or in combination with other flame retardants, synergists or adjuvants. |