The structure and rheological properties of block copolymers based on butadiene and styrene

The influence of structure on the rheological properties of butadiene-styrene block copolymers of linear (DSTL 30-01), radial (DSTR 30-00) structure, as well as linear thermoplastic elastomer Kraton G 1650E (SEBS) with hydrogenated elastic block has been investigated by methods of infrared spectroscopy and rotorless rheometry. The flow curves of thermoplastic elastomers in the temperature range from 140°C to 190°C were obtained. It has been established that they are characterized by the effect of an extreme decrease in viscosity in the range from 155°C to 170°C, associated with a change in the physical state of the polystyrene phase and possible partial mutual dissolution of styrene and butadiene fragments.