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Theoretical prediction of the performance of adsorbed polymeric dispersion stabilizers requires information on the configuration of polymers at the solid/liquid interface. Parameters describing polymer adsorption configuration on aqueous polystyrene latices are evaluated for representative linear homopolymers, block copolymers, and random copolymers of polyethylene oxide) and poly (propylene oxide). Effective hydrodynamic adsorption layer thicknesses, determined with photon correlation spectroscopy, are reported for the different polymer systems as a function of molar mass, concentration, and time from initial mixing. Specific adsorption isotherms are also determined. The data suggest that the polymers adsorb in the extended configuration, as loops and/or tails.Polymers and Colloids.Registry No. PEO (homopolymer), 25322-68-3; (PEO)-(PPO)-(block copolymer), 106392-12-5; (PEO)(PPO)(copolymer), 9003-11-6; polystyrene, 9003-53-6.

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A simple apparatus was designed and constructed capable of measuring the unsteady‐state permeability and the capillary pressure simultaneously in a simulated composite impregnation experiment. It was found that the Kozeny‐Carman equation used to describe the permeability of composites during impregnation adequately described experimental results for woven fabric preform up to porosity values of 0.5. Above this value, observed deviations were attributed to interfacial effects between adjacent woven fabric layers. For woven fabric preforms made of T‐300 carbon fibers, a maximum capillary pressure of 3.7 × 104 Pa (=5.4 psi) was observed at low porosity values. Thus, the capillary pressure may compete with other pressure sources in low pressure processes, such as the prepregging process. The woven fabric preform used in this study is observed to have a permeability similar to a unidirectional fibrous preform along the transverse direction. Furthermore, an existing modeling methodology capable of predicting permeability and capillary pressure through different preforms was found to be valid for fibrous preforms of complex orientation.