Four different polyester plasticizers for poly(vinyl chloride) (PVC), havin
g moderate acid numbers (11.5-20.5 mg KOH/g resin), were synthesized. These
were modified by converting the terminal group to Ba(II) and Cd(II) carbox
y-late salts-in order to introduce the capability of heat stabilization for
PVC. The modified polyesters were applied as dual function polyesters, i.e
., a plasticizers and stabilizers at the same time. The thermal stabilizati
on efficiency of the formed plasticized PVC films was tested photometricall
y and the data obtained were compared with that afforded by "Irgastab BZ 55
6". The efficiencies of these modified polyesters as heat stabilizers for P
VC were found to be comparable with that afforded by "Irgastab BZ 556".