The interfacial thickness of symmetric diblock copolymers: Theory and experiment

A recent application of density functional theory to the structure and thermodynamics of the ordering of symmetric, tangent hard site, diblock copolymers [S. K. Nath et al., J. Chem. Phys. 106, 1950 (1997)] predicted an interfacial thickness larger than would be expected from previous self-consistent-field studies of thread chains. Here we compare the theoretical predictions with the few experimental measurements of interfacial thickness in symmetric diblocks. It is observed that predictions of the thickness of the interface are sensitive to the details of the monomer structure included in the underlying model, and that the range of the experimental measurements is spanned by the two theoretical models.