Changes in the appearance of rubber products after aging

Different rubber varieties, different conditions of use, different changes occur.
Softening and sticking:Thermal oxidation of natural rubber, aging of chlorohydrin rubber.
Hardening and brittleness: thermal oxidation of male rubber, aging of nitrile rubber and styrene butadiene rubber.
Cracking: Ozone aging of unsaturated rubber, photo-oxidative aging of most rubbers, but the shape of cracking is different.
Mold: Biological microbial aging of rubber.
In addition: spots, cracks, frosting, chalking and whitening.