There are disclosed polymerizable thioester synergists which have utility in enhancing the anti-oxidative activity of phenolic and amine stabilizers. The invention is also concerned with the thioesters themselves, their use in oxidizable organics, their combination with polymerizable and/or conventional antioxidants, and with polymers which contain these thioesters as physical admixtures or segmeric units of the polymer.
The present invention relates to thioesters having the structural formula:
wherein Rx is selected from the group of formulae consisting of:
R¹, R² and R³ are independently selected from the group of radicals consisting of hydrogen or methyl; R⁴ and R⁵ are independently selected from the group of radicals consisting of hydrogen, alkyls having 1 to 18 carbon atoms, aryls having 6 to 10 carbon atoms, aralkyls having 7 to 9 carbon atoms, and radicals of the formula:
and R⁶ is selected from the group of radicals consisting of alkyls having 1 to 24 carbon atoms, aryls having 6 to 12 carbon atoms and aralkyls having 7 to 12 carbon atoms.
These thioesters are particularly useful as a synergist for conventional phenolic and amine antioxidants.