Neutron Reflectivity Study of Block Copolymers Adsorbed from Solution

We report neutron reflectivity experiments from solution of symmetric diblock copolymers of polystyrene and poly(methyl methacrylate), P(S-b-MMA), near a quartz wall in carbon tetrachloride. This solvent is a good solvent for the PS block but a poor solvent for the PMMA block. When all four combinations of hydrogen and deuterium labeling of the blocks are utilized, it is shown that the PMMA block strongly adsorbs onto the quartz substrate forming a PMMA-rich layer of 30 Å, comparable to its radius of gyration, with a volume fraction of 0.42. However, the concentration of polystyrene segments beyond this initial layer of PMMA is too low to be determined by these experiments. © 1990, American Chemical Society. All rights reserved.