Evidence of crosslinks in a butadiene-divinylbenzene-ethylvinylbenzene copolymer by metathesis degradation

1,3‐Butadiene was copolymerized with a mixture of divinylbenzene isomers containing ethyl‐vinylbenzene isomers. The crosslinked copolymers were degraded in a cross metathesis reaction with (Z)‐2‐butene or (E)‐3‐hexene using the catalyst WCl6/Sn(CH3)4. The low‐molecular‐weight products were investigated by gas chromatography/mass spectrometry coupling. Products containing the crosslinks were found. Others were attributable to copolymer units resulting from butadiene and ethylvinylbenzene. Characteristic mass spectra of the products are discussed.