STABILIZATION OF POLYPROPYLENE BY ESTERS OF 2,2,6,6 - TETRAMETHYL 4-PIPERIDINOLE

The effect of the substituents R and X in esters of 2,2,6,6‐tetramethyl‐4‐piperidinole of the general formula 1 (Formula Presented.) on their stabilizing efficiency in polypropylene was investigated. As the substituents R, the aliphatic alkyls CH3 (CH2)n were used, where n=0‐16, X=H. By the derivative where R is an alkyl with 13 to 17 carbon atoms the affect of the substituent X was also investigated where X is H, 0, OH, OR. Both the thermooxidation and photooxidation stability of PP were found to be increased with the increasing chain length R. The effect of the substituents X is various. Both and stabilizers have high efficiency during the processing of PP. At the long‐term thermooxidation stress, the , and derivatives are more efficient than compounds which are the most efficient against the effect of the ultraviolet radiation and photooxidation. © 1990 Hüthig & Wepf Verlag, Basel