abstract |
N-(2,2,6,6-tetraalkyl-4-piperidinyl)amide-hydrazides of dicarboxylic acids contain a light stabilizing group, a heat stabilizing group, and a reactive hydrazide functionality in the same molecule. The reactive stabilizers are prepared by reacting 4-amino-2,2,6,6-tetraalkylpiperidines with diesters (or mono ester acid chlorides) of dicarboxylic acids or dialkyl itaconates followed by hydrazinolysis of the ester group of the intermediate mono esteramide. The compounds are useful for introducing permanent heat and light stability to coreactive polymers or copolymers. They are also useful in the stabilization of inert polymeric systems against the degradative effects of heat and light when merely mixed with, rather than reacted with, the polymers for which stabilization is sought. |