Styrene/2-vinyl pyridine block copolymer interface

Figure 6.16. Segregation of a deuterium-labelled styrene-vinyl pyridine block copolymer to an interface between polystyrene and poly(vinyl pyridine), revealed by forward recoil spectrometry. The block copolymer was initially imiformly distributed in the upper, polystyrene film after annealing for 8 h at 178 °C an interfacial excess of 100 A has developed. After Shull etal. (1990).

Figure 7.9. Interfacial reinforcement of a polystyrene/poly(vinyl pyridine) interface by a high relative molecular mass deuterated styrene-vinyl pyridine block copolymer, with degrees of polymerisation of each block 800 and 870, respectively. Circles (right-hand axis) show the measured interfacial fracture energy as a function of the areal chain density of the block copolymer 2, whereas crosses show the fraction of dPS found on the polystyrene side of the interface after fiacture. The discontinuity in the curves at 2 = 0.03 nm is believed to reflect a transition from failure by chain scission to failure by crazing. After Kramer et al. (1994).

Figure 6.17. The excess of styrene-2-vinyl pyridine block copolymer at a polystyrene/ poly(2-vinyl pyridine) interface, determined by forward recoil spectrometry. The degrees of polymerisation of the styrene and vinyl pyridine blocks were 391 and 68, respectively. The solid line is the prediction of self-consistent field theory, assuming a value for the Flory-Huggins interaction parameter %ps-pvp of 0.11. After Shull et al. (1990).

Figure 7.4. Fracture energies of interfaces reinforced by block copolymers as a function of the effective areal density of chains crossing the interface. Triangles and squares are for polystyrene/poly(2-vinyl pyridine) interfaces reinforced with styrene-2-vinyl pyridine block copolymers (Creton et al. 1992) circles are for poly(xylenyl etherypoly(methyl methacrylate) interfaces reinforced with styrene-methyl methacrylate block copolymers (Brown 1991a, b). After Creton et al. (1992).

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