Competition between micellization and adsorption of diblock copolymers in a colloidal system
Article first published online: 10 MAR 2003
Copyright © 1995 John Wiley & Sons, Inc.
Journal of Applied Polymer Science
Volume 58, Issue 2, pages 265–269, 10 October 1995
How to Cite
Dewalt, L. E., Ou-Yang, H. D. and Dimonie, V. L. (1995), Competition between micellization and adsorption of diblock copolymers in a colloidal system. J. Appl. Polym. Sci., 58: 265–269. doi: 10.1002/app.1995.070580205
- Issue published online: 10 MAR 2003
- Article first published online: 10 MAR 2003
- Manuscript Accepted: 9 APR 1995
- Manuscript Received: 18 FEB 1995
Significant adsorption of polystyrene-poly(ethylene oxide) (PS-PEO) diblock copolymers onto PS latex particles in an aqueous dispersion is accomplished through suppression of micelle formation by adding tetrahydrofuran (THF) as a cosolvent. We add THF, a good solvent for the micelle core, to weaken the micelle and allow free chains for adsorption to the colloidal particles. Choosing a PS colloidal particle as the adsorption substrate (thus the adsorbed PS block can fully wet the subsurface), we eliminate the complications which arise from micelle formation on the colloidal surface. Since the PS particles swell in the mixed solvent, the adsorbed PS block may penetrate into the swollen latex core, which is favored for entropic reasons. A subsequent water quench of the system to a low THF solution shrinks the PS particle to its original size while retaining most of the adsorbed polymers. The adsorbed chains cannot be removed by adding surfactants or raising temperature to 90°C, indicating that the adsorbed layer is tightly attached to the surface due to kinetic hinderance of the chains in a confined environment. Neutron scattering experiments is being carried out to settle whether the PS penetrates the PS particle. © 1995 John Wiley & Sons, Inc.