Epoxy based thermal stabilizer for poly(vinylchloride)

A tetrafunctional epoxy resin was prepared and characterized by epoxy equivalent weight, percentage nitrogen, IR spectroscopy and number average molecular weight (M n ) determined by GPC. The resin was evaluated as a thermal stabilizer for polyvinylchloride (PVC). The stabilizing efficiency was tested by yellowness index, HCl liberation, UV absorption, induction time, and changes in mechanical properties (tensile strength, elongation at break and Shore-A hardness). Epoxy resins with several epoxy groups are effective as in stabilizing PVC against dehydrochlorination during processing and use, compared with tribasic lead sulphate. The replacement of lead based stabilizers by epoxy stabilizers will remove the toxic effect of lead in water flowing through PVC pipes.