Mechanical properties of poly(styrene-b-n-butylmethacrylate) diblock copolymers, PS-b-PBMA, with different lengths of the polystyrene block were investigated. The copolymers display a composition range where the tensile strength of the block copolymers exceeds the values of the corresponding homopolymers. At a PS-content of 74 vol% not only the tensile strength but also the strain at break is higher than that of pure polystyrene. Furthermore, the absorbed energy shows a maximum at a polystyrene content of 29 vol%. This composition reveals a morphology of hexagonally packed PS-cylinders which turns out to be effective for the increase of toughness in PS-b-PBMA diblock copolymers. The improved properties of PS-b-PBMA diblock copolymers are discussed with respect to a possible correlation and synergism between phase behaviour, morphology, deformation mechanism, and interface formation.
Посилання на статтю:
Mechanical properties of weakly segregated block copolymers: 1. Synergism on tensile properties of poly(styrene-b-n-butylmethacrylate) diblock copolymers / R. Weidisch, G.H. Michler, H. Fischer, M. Arnold, S. Hofmann, M. Stamm // Polymer. – 1999. – N 40. – P. 1191–1199.