PHYSICAL GELATION OF POLYSTYRENE-BLOCK-POLY(ETHYLENE BUTYLENE)-BLOCK-POLYSTYRENE COPOLYMER IN PARAFFINIC OIL - OSCILLATORY SHEAR AND COMPRESSION MEASUREMENTS/

The thermoreversible gelation of the triblock copolymer ne-block-poly( ethylene/butylene)-block-polystyrene (SEBS2) in paraffinic oil was stu died. The solvent used is selective for the middle PEP block of the co polymer. The thermal behaviour as a function of copolymer concentratio n was investigated. The sol-gel transition temperature increases with the copolymer concentration. The mechanical properties were examined t hrough oscillatory shear and compression measurements. The concentrati on dependence of the elastic storage modulus, G', was established. The relaxation rates observed were extremely high, indicating a considera ble mobility in the gel during the measurement time.