Mobile nanoparticles and their effect on phase separation dynamics in thin-film polymer blendsH.-J. Chung, A. Taubert, R. D. Deshmukh and R. J. Composto
Department of Materials Science and Engineering and Laboratory for Research on the Structure of Matter, University of Pennsylvania Philadelphia, PA 19104-6272, USA
received 7 June 2004; accepted in final form 30 August 2004
We present a systematic study of mobile nanoparticles (NP) and their effect on phase separation dynamics in polymer blend films. Starting with a homogeneous dispersion of silica NP in films, the NP are observed to partition into the PMMA-rich phase and stratify during phase separation. The correlation length between phases grows as for blends containing 0, 2, and 5 % NP. However, phase size decreases as the wt% of NP increases. This behavior agrees with a coalescence model, which incorporates an increase in viscosity due to the NP.
64.70.Ja - Liquid-liquid transitions.
82.35.Np - Nanoparticles in polymers.
68.55.-a - Thin film structure and morphology.
© EDP Sciences 2004