Elasticity of sphere-forming polystyrene-b-polyisoprene-b-poly(2-vinylpyridine)/polystyrene-b-polyisoprene/ polyisoprene-b-poly(2-vinylpyridine) blends: The role of dangling chains

The relationship between the young's moduli and bridge/dangling chain fractions for the SIP used in studies was analyzed. Two diblock copolymers, SI and IP were synthesized by anionic polymerization technique as SIP. The blend samples were prepared by solvent casting from dilute THF solutions of samples for a few days and further dried for 6h and annealed at 150 °C for 12 h in a vacuum oven. Dynamic elongation measurements were performed with Rheometric Solid analyzers. It was observed that there was dependence between storage modulus and loss modulus measured for all samples. The results show that young's moduli of sphere-forming triblock copolymers are proportional to the bridge fraction and the difference between dangling ends and loops are very minor.