To prevent rubber aging, additives that effectively inhibit oxidation reactions are often added to the rubber. These rubber antioxidants can be classified into the following categories based on their chemical properties and mechanisms of action:
(1) Physical adsorbents: such as silica, which adsorb pollutants such as moisture and oxygen inside the rubber, thus delaying rubber aging.
(2) Cyanide-reducing agents: such as amphetamine and N-phenyl-α-naphthylamine, which interact with reactive oxygen species, consuming free radicals and thus delaying rubber aging.
(3) Amine bactericides: such as N,N-dimethyl-p-phenylenediamine, which reduce the aging rate of rubber by inhibiting free radical reactions.
(4) Antioxidants: such as NaUGO, which react directly with oxygen, counteracting or reducing the oxidative effect of oxygen on rubber.
(5) Catalysts: such as phenolic resins, which promote internal reactions within rubber molecules through their own catalytic action, thereby reducing the aging rate of rubber.
