Self extinguishing polymeric compositions, which upon contacting a flame provide a nondropping char-forming incandescent crust, and which do not produce flame neither toxic fumes

摘要

There are described certain polymeric compositions which are made flame retarding, provide an incandescent char-forming crust, are not dropping and do not promote toxic fumes, in view of the addition, on 100 parts in weight of polymer, of 5-40 parts in weight of the reaction product between an acid of the phosphorus and at least a hydroxyalchyl derivative of at least a compound selected between the isocyanuric acid, the melamine and the urea, and, in a modified embodiment, in addition to the above indicated reaction product, of 5-30 parts in weight of a polymer of an ammonium polyphosphate of formula (NH.sub.4 PO.sub.3).sub. n", wherein n" is greater than 20. In a further modified embodiment there is added amine phosphate, such as the ortho- or pyrophosphate of melamine, in amount of 1-10 parts in weight. The reaction product as above comprises in its molecule the formula ##EQU1## Where R is at least a linear or branched alkylene derivative, n' is comprised between 1 and 6, and P is tri- or pentavalent.