Linear copolyester containing phosphorous, procedure for its preparation and its use as a flame-retardant additive

摘要

A linear copolyester is prepared by polycondensation of an aromatic bicarboxylic acid with an alkylene glycol and with a carboxyphosphinic acid or anhydride which produces monomeric units having the formula: ##STR1## wherein R.sub.1 is an alkylene or phenyl radical and R.sub.2 is an alkyl or phenyl radical.PPThis copolyester can be used as a flame-retardant additive for organic polymers.