Natural rubber photo-oxidation

Pyrolysis of synthetic polyisoprene in the presence of oxygen also is expected to be identical to that of natural rubber. Thermal oxidation of natural rubber is assumed always to be associated with scission, although photo-oxidation at low temperature may involve peroxide formation without scission. The effect of oxygen is to increase the reaction rate of scission and therefore to decrease the temperature where the scission starts. The oxidation may take place after the initial formation of a free radical that reacts with oxygen ... 

Ot and photo-oxidants Pulmonary oedema, emphysema, asthma, eye. nose, and throat irritation, reduced lung capacity. Vegetation damage, necrosis of leaves and pines, stunting of growth, photosynthesis inhibitor, probable cause of forest die-back, suspected cause of crop loss. Attack and destruction of natural rubber and polymers, textiles and materials. 

Natural rubber was also studied regarding pyrolysis in the presence of oxygen. Thermal oxidation of natural rubber is assumed always to be associated with scission, although photo-oxidation at low temperature may involve peroxide formation without scission. 

Styrene-butadiene rubber, similar to natural rubber, is only slightly resistant to light attack and in particular to photo-oxidative degradation. In contrast to natural rubber, crosslinking is dominant [32]. 

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