This value is determined from both *H NMR and 2H NMR measurements of the polymer with (CD2)10 spacer of a relatively low molecular weight.22 It is somewhat larger than s 0.6 obtained in ref 11 from the measurement of diamagnetic anisotropy of a high molecular weight polymer. This difference is most likely due to the difficulty in achieving complete alignment of the high molecular weight polymer under the applied magnetic field in the latter experiment.

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We present a theoretical study of the lamellar structure of diblock copolymers blended with neutral solvent. The calculations are based on numerical solutions of the equations of the mean field self-consistent theory of incompressible polymer/solvent blends, from the weak through to the strong segregation limits. For idealized model systems of symmetric copolymers and perfectly nonselective solvent, we examine the variation of the equilibrium lamellar thickness with molecular weight, Flory χ parameter, solvent quality, and copolymer volume fraction, as well as the distribution of solvent and polymer within the subdomains. We also examine a real system which has been extensively studied experimentally, namely PS-b-PI with the (nearly) nonselective solvent toluene.

We present a study of adsorbed diblock copolymers, which is based on the mean-field selfconsistent theory of incompressible polymer/solvent blends. We assume that one of the blocks is tightly adsorbed and model the remaining block using the formalism recently developed for crystallizable/ amorphous block copolymer blends. Restricting attention primarily to near-9 conditions, we present series of calculations describing adsorption at a single surface and adsorption on two parallel surfaces a finite distance apart. For the second case, we calculate the long-range forces acting on the two surfaces. We make quantitative comparisons with experiment for conditions corresponding to slightly good, 0, and slightly poor solvents. We determine the thickness and shape of the polymer density profiles, obtain approximate scaling relations and the ranges of their applicability, study finite molecular weight effects, as well as the extent of the interdigitation of layers adsorbed on opposite surfaces, and show how these quantities vary as the surface separation changes. In addition, we show how the scaling of the apparent range of the measured long-range force can differ from the scaling of the thickness of a single adsorbed layer.