The polymer is usually in an anoxic state under extrusion processing conditions, and the system contains a large number of carbon radicals rather than alkoxy radicals and hydroxyl radicals. Therefore, the ideal processing stabilizer should be able to capture carbon free radicals effectively. The hydroxylamine antioxidant mentioned above is a kind of carbon radical trapping agent.
The main carbon free radical trapping agents in the market are hydroxylamine, bisphenol mono-acrylate, ortho acrylyl substituted phenol and benzofuranone several categories.
Bisphenol monoacrylate antioxidants:
In bisphenol monoacrylate molecules, the carbon radical is captured by the acrylyl group, and the enol radicals generated can be converted into stable phenolic oxygen radicals by the hydroxyl functional group in the same molecule. This effect is known as the bifunctional stabilization mechanism. This gives bisphenol monoacrylate a very strong free radical trapping ability. Its stabilization is strong even at high temperatures. Companies in Japan and Europe have launched such products. At present, Sumilizer GM by Sumitomo Chemical, IRGANOX 3052 by BASF, and AO3352/AO3353 are mainly used in the market.
| PRODUCT | AO3352 | AO3353 |
| CAS NUMBER | 61167-58-6 | 123968-25-2 |
| APPEARANCE | WHITE POWDER | WHITE CRYSTAL POWDER |
| ASSAY(%) | 99.00 MIN | 99.00 MIN |
| MELTING POINT(℃) | 130.00 MIN | 115.00 MIN |
| VOLATILES(%) | 0.30 MAX | 0.50 MAX |
| ASH(%) | 0.10 MAX | 0.10 MAX |
| APPLICATION | Widely used in PP, PE and other polyolefin, ABS, HIPS, EPDM, SBR and other elastomers. | Widely used in adhesives, styrene thermoplastic elastomers, ABS, polystyrene and rubber modified polyphenylethylene and other fields. It can effectively capture alkyl radicals, and performs synergistic effect with benzotriazole UV absorbers and HALS light stabilizers. In the adhesive elastomer, it has a good synergistic effect with phenolic antioxidants and phosphite ester antioxidants. |