Sulfur Dioxide with 1,5-Cyclooctadiene—General Method

Copolymerization of Sulfur Dioxide with 1,5-Cyclooctadiene—General Method [52] 

All polymerizations are carried out in roimd-bottom flasks fitted with a dry ice 

After c/5,ds-1,5-cyclooctadiene, b.p. 67°-68°C (46 mm) ( + 99.8% pure VPC), and the distilled solvents are added, the flask is chilled to - 70°C and anhydrous sulfur dioxide, as a liquid, is transferred under nitrogen to the flask. With the flask still at - 70°, the catalyst is added and the reaction mixture allowed to rise to the reflux temperature of the given mixture. The time of reaction noted in Table XI refers to elapsed time from the addition of the catalyst to the precipitation of the reaction mixture. For those mixtures in which such polymer solvents as dimethyl sulfoxide and tetramethylene sulfone are used, the polymer remains in solution and is precipitated by the addition of methanol. For nonsolvents the polymer is precipitated by the addition of methanol. For non-solvents the polymer is precipitated during the polymerization. In all cases, the isolated 

Wave length (pm) Intensity Wave length (pm) Intensity 

30 (B) Copolymer of sulfur dioxide and cis,cis-1,5-cyclooctadiene (I) Medium 7.80 Strong 

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