Double Yielding in a Styrene/Butadiene Star Block Copolymer

The morphology and tensile deformation behaviour of a highly asymmetric styrene/butadiene star block copolymer (polystyrene (PS) content = 74%) containing random PS-co-PB (polybutadiene) copolymer as a rubbery phase were investigated. The existence of double yielding, similar to that observed in some semicrystalline polymers, was detected in this nanostructured amorphous polymer. The observed phenomenon may be correlated with two different micromechanical processes taking place at the initial stage of deformation.

[1]  G. Michler,et al.  Correlation between Molecular Architecture, Morphology, and Deformation Behaviour of Styrene/Butadiene Block Copolymers , 2003 .

[2]  G. Michler,et al.  Morphology and micromechanical deformation behavior of styrene/butadiene‐block copolymers. I. Toughening mechanisms in asymmetric star block copolymers , 2002 .

[3]  K. Knoll,et al.  Microstructure and rheological properties of triblock copolymers under extrusion conditions , 2002 .

[4]  Lin-Xian Feng,et al.  Tensile behaviour of homogeneous ethylene copolymers , 2002 .

[5]  K. Knoll,et al.  Styrolux+ and styroflex+ ‐ from transparent high impact polystyrene to new thermoplastic elastomers: Syntheses, applications and blends with other styrene based polymers , 1998 .

[6]  J. L. Feijoo,et al.  The phenomenon of double yielding in oriented high density polyethylene films , 1997 .

[7]  R. Seguela,et al.  Tensile Yield of Polyethylene and Related Copolymers: Mechanical and Structural Evidences of Two Thermally Activated Processes , 1997 .

[8]  A. Peacock,et al.  The double yield in the tensile deformation of the polyethylenes , 1995 .

[9]  I. Ward,et al.  Modeling of double yield points in polyethylene: Temperature and strain‐rate dependence , 1995 .

[10]  I. Ward,et al.  Double yield points in polyethylene: Structural changes under tensile deformation , 1995 .

[11]  R. Seguela,et al.  Phenomenological aspects of the double yield of polyethylene and related copolymers under tensile loading , 1994 .

[12]  V. Balsamo,et al.  The phenomenon of double yielding under tension in low-density polyethylene, linear low-density polyethylene and their blends , 1993 .

[13]  I. Ward,et al.  Investigation into double yield points in polyethylene , 1992 .

[14]  L. Mandelkern,et al.  Influence of structural and morphological factors on the mechanical properties of the polyethylenes , 1987 .

[15]  M. Takayanagi,et al.  Structural factors in deformation of crystalline polymers , 1973 .

[16]  M. Takayanagi,et al.  Study of fine structure of viscoelastic crystalline absorption in polyethylene single crystals , 1967 .