Piperidine-phenols stabilizing activity

In addition, we attempted to prepare piperidine compounds bonded with a hindered phenol moiety, since phenolic antioxidants are essential for processing and long-term stabilization. The proposed compounds were expected to have light-stabilizing activity and at the same time thermal stabilizing activity in the polymers. Bifunctional compounds were also synthesized. The corresponding diols were obtained by the reaction of the amines with ethylene oxide (Chart 11). The stabilizing activities of the above compounds are summarized in Table V. 

Attachment of B ansformation Products of Stabilizers. Up-to-date knowledge dealing with the chemistry of transformation products of phenolic [6, 15, 17, 20] and aromatic aminic [16, 43, 230] antioxidants and photoantioxidants based on hindered piperidines [10] indicates the possibility of attaching compounds having structures of quinone imine or quinone methide, or of radical species like cyclohexadienonyl, phenoxyl, aminyl or nitroxide to polymeric backbones. These reactions proceed mostly via reactivity of macroalkyl radicals derived fi-om stabilized polymers. Various compounds modelling this reactivity have been isolated [19, 230]. These results are of importance mainly for the explanation of mechanisms of antioxidant activity [6, 22, 24]. 

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