Significant aspects of the free radical chemistry of 2,2,6,6,-tetramethylpiperidinederivatives (HALS) which are of interest in respect to the mechanism of inhibition of polyolefin photo-oxidation have been elucidated by performing an ESR study of the reactions initiated by t-butoxyl radicals. With unsubstituted 2,2,6,6,-TMP the preferred site of the H-abstraction is the NH bond; this selectivity is preserved also when activated CH bonds adjacent to ester groups are present. The reactions of the aminyl radical products with the parent molecules and other reactive compounds have been followed by kinetic ESR and their rate constants and activation energies measured.
Radicalreactivity of 2,2,6,6,-tetramethylpiperidinederivatives: A kinetic ESR study
FAUCITANO, ANTONIO;BUTTAFAVA, ARMANDO;MARTINOTTI, FAUSTA;
1985-01-01
Abstract
Significant aspects of the free radical chemistry of 2,2,6,6,-tetramethylpiperidinederivatives (HALS) which are of interest in respect to the mechanism of inhibition of polyolefin photo-oxidation have been elucidated by performing an ESR study of the reactions initiated by t-butoxyl radicals. With unsubstituted 2,2,6,6,-TMP the preferred site of the H-abstraction is the NH bond; this selectivity is preserved also when activated CH bonds adjacent to ester groups are present. The reactions of the aminyl radical products with the parent molecules and other reactive compounds have been followed by kinetic ESR and their rate constants and activation energies measured.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
