The top 10 hindered phenol antioxidants are not a universal ranking; selection depends on the polymer, processing temperature, and end use. Common choices include butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), 2,2′-methylenebis(4-methyl-6-tert-butylphenol), 4,4′-thiobis(6-tert-butyl-3-methylphenol), and 2,2′-methylenebis(4-ethyl-6-tert-butylphenol). The list also includes tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) of pentaerythritol, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N′-hexamethylene bis(3,5-di-tert-butyl-4-hydroxyhydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and a tris(hydroxybenzyl) triazine-trione derivative.
Why so many? Their molecular size and compatibility differ. Smaller molecules such as BHT can be easier to incorporate, while larger structures are often selected when low volatility or reduced migration matters. These are tendencies, not guarantees. Formulation and processing tests still matter.
Plastics Europe’s Plastics – the Fast Facts 2023 reports global plastics production of 400.3 million tonnes in 2022. That scale helps explain the need to protect polymer materials from oxidation during processing and use, but it does not establish which antioxidant performs best. For comparison, ASTM D3895 measures oxidation induction time in polyolefins. A longer result can be useful, yet it should not replace testing under real processing conditions. Small differences in heat history can change the outcome.