Hydroxyl‐terminated cotelomers of butadiene and bromostyrene

The synthesis of hydroxyl-terminated cotelomers of 1,3-butadiene and bromostyrene was studied. Hydrogen peroxide was used in solution copolymerization to obtain cotelomers of average molecular weights of 1000–4000. The higher the hydrogen peroxide concentration, the broader the molecular weight distribution. The molecular weight is apparently unaffected by the hydrogen peroxide concentration within the limits studied. The concentration of bromostyrene in the products is correlated with its concentration in the monomers. Microstructure of the cotelomers is analyzed. Vinyl content is about 25% of the butadiene content. A correlation of the glass transition temperatures of the cotelomers with those of pure polybromostyrene and polybutadiene is discussed.