Effect of diblock copolymers on dynamic mechanical properties of polyethylene/polystyrene blends

摘要: A systematic investigation of the dynamic mechanical properties high-density polyethylene (HDPE)/high-impact polystyrene (HIPS)/copolymer blends was carried out. Blends 80/20 weight percent HDPE/HIPS were prepared in melt state at 180°C a batch mixer. Synthesized pure diblock (H77) and tapered (H35) copolymers hydrogenated polybutadiene (HPB) (PS) added different concentrations (1, 3, 5 wt %), investigated. The results show that: (1) both enhance phase dispersion interphase interactions; (2) structure molecular are important parameters design copolymers; (3) effects occur when only small amounts copolymer (up to interface saturation concentration SC); (4) micellar formation is possible excess blend; (5) effect on SC critical (CMC) more pronounced than weight. These found be lower for copolymer. analysis thermal (DMTA) obtained 20/80 blend leads conclusion that also interactions between heterogeneous phases. Similar conclusions based electron microscopy reported literature. DMTA shows great potential relate macroscopic observations an immiscible blend.