Aromatic flock copolyesters stabilised with metallic salts of phosphinic acid

Stabilisers consisting of metallic salts of p-butoxyphenylcyclohexyl phosph inic acid were introduced into two industrial copolymers based on bisphenol -A and phenolphthalein respectively, and their effects on the mechanical an d thermal properties were investigated. The mechanical properties were sens itive to the amount of stabiliser. Ductility and breaking strength increase d with small additions, but as the amount of stabiliser increased, the proc ess was reversed. On the other hand the modulus of elasticity showed a stea dy decrease. Similarly, the thermal stability also increased with small con centrations of additive, and decreased at higher concentrations. Heat treat ment increased the brittleness and reduced the breaking strength.