In-situ Polymerization: Its Effect on Polymer Structure.

Blends of polybutadiene and polystyrene have been prepared by an in-situ polymerization technique. The chemical structure of the polybutadiene prepared with a Ti(0Bu)(4) catalyst was dependent on the difference between the polymerization temperature and the glass transition temperature (T(g)) of the matrix. For example, at temperatures well below the T(g) of the polystyrene- catalyst film significantly more cis 1,4 polybutadiene was produced. These results were not repeated when a V(III)acac catalyst was used.