Investigation of equilibrium and non‐equilibrium states of polymer blends by small‐angle neutron scattering

摘要

Small‐angle scattering of neutrons (SANS) has been applied to investigate the equilibrium properties of polymer blends, in particular the critical fluctuations in the homogeneous regions ford‐PS/PS, PS/d‐PB andd‐PS/PVME. The transition between mean‐field and Ising behaviours has been observed for PS/d‐PB about 6 K aboveTc. The non‐equlibrium behaviour of the SANS structure factor ofd‐PS/PS has been studied after a temperature step has been applied. Only for very small scattering vectors does the time‐dependent structure factor follow the predictions of the Cahn–Hilliard theory. Also, early stages of decomposition within the miscibility gap have been studied in this system and ind‐PS/PVME. PS = polystyrene; PB = polybutadiene; PVME = po