Cis-l,4-polybutadiene in carbon tetrachloride solution

Irradiation of a dilute solution of cis-l,4-polybutadiene in carbon tetrachloride (CCI4) with UV radiation in air causes the formation of a white insoluble gel. The observed crosslinking reaction is caused by reactive radicals formed from photolysis of CCI4 [1115]  

These radicals can abstract hydrogen from methylene groups (—CH2—) and/or can react with double bonds  

The chlorinated polymeric radicals (3.102) react further with oxygen to give polymer peroxy radicals (3.103)  

Polymer peroxy radicals (3.103) abstract hydrogen from the polymer molecules (PH) and produce polymer hydroxyperoxides (3.104)  

All polymer radicals formed (3.102), (3.103) and (3.104) may participate further in crosslinking reactions giving an insoluble gel  

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