“Mechanically–Induced Generation of Counterions Inside Surface–Grafted Charged Macromolecular Films: Towards Enhanced Mechanotransduction in Artificial Systems”.

O. AZZARONI; B. TRAPPMANN; P. VAN RIJN; F. ZHOU; B. KONG; W.T.S. HUCK

Angewandte Chemie

Año: 2006 p. 7440 - 7443

1433-7851

In seminal work, Klein and co-workers have shown that two surfaces coated with strong polyelectrolyte brushes exhibited significantly improved lubrication because of resistance of the brushes towards collapse. The crucial observation we report here is that deliberate mechanical compression of strongly charged polyelectrolyte brushes in pure water should lead to a state where the microenvironment in the brush layer resembles the high ionic strength environment that would otherwise lead to collapse so as to minimize Coulombic repulsions between the charges on the brushes. To put this idea into practice we exploited the ionization of dye molecules immobilized inside polyelectrolyte brushes upon mechanical deformation of the surface-grafted polymer chains.