Acta Phys. -Chim. Sin. ›› 2008, Vol. 24 ›› Issue (08): 1487-1492.doi: 10.3866/PKU.WHXB20080827

• ARTICLE • Previous Articles     Next Articles

Stratification in Bimodal Polymer Brushes

SUN Zhe; SONG Hai-Hua   

  1. School of Chemistry and Chemical Engineering, Tianjin University of Technology, Tianjin 300384, P. R. China; School of Chemical Engineering, Tianjin University, Tianjin 300072, P. R. China
  • Received:2008-02-10 Revised:2008-04-19 Published:2008-08-06
  • Contact: SUN Zhe E-mail:zhesun@tjut.edu.cn

Abstract: The density profiles in a mixture of bimodal polymer brushes and solvent were simulated with the aid of a self-consistent field theory (SCFT). The results showed that the bimodal brushes in good solvent form two sub-layers, which were in good agreement with those from both experiments and Monte Carlo simulations. And the increase of solubility not only makes the density profiles obtained by SCFT close to the results calculated with strong segregation theory (SST) asymptotically, but also leads to further stretching of polymer chains and sufficient orientation of chain segments. Moreover, the enlargement of grafting densities facilitates the stratification of brushes. In good solvent condition, density profiles with different total grafting densities could fall onto the same master curve. Additionally, polymerization index of long chains plays an important role in stretching of long chains, but it has little effect on density profiles of short chains.

Key words: Polymer brushes, Self-consistent field theory, Stratification, Morphology

MSC2000: 

  • O641