Kinetics of Shear Microphase Orientation and Reorientation in Lamellar Diblock and Triblock Copolymer Melts as Detected via FT‐Rheology and 2D‐SAXS

Abstract

AbstractThe microphase orientation/reorientation alignment kinetics behaviour of lamellar PS‐b‐PB diblock and PS‐b‐PB‐b‐PS triblock copolymers under LAOS conditions is studied. By online monitoring the degree of the mechanical nonlinearity during the orientation process, as determined via the higher harmonics in FT rheology [i.e: I3/1(t), ϕ3(t)], and investigation of the orientation distribution by 2D‐SAXS, the kinetics of the microphase alignment for different experimental shear conditions was followed. For di‐ and triblock copolymers, the shear orientation into parallel alignment is possible and the kinetics of orientation is strongly dependent on the strain amplitude.magnified image