Polyelectrolyte-mediated undulation of surfactant bilayers

We studied the effect of the cationic polyelectrolyte poly(diallyldimethylammonium chloride) (PDADMAC) on the highly dilute lamellar $L_{\alpha }$ phase formed by the nonionic surfactant triethylene glycol monodecyl ether ${(\mathrm{C}}_{10}{\mathrm{E}}_3)$ in water. Upon addition of PDADMAC, light scattering shows nonlamellar order, indicating the formation of strongly undulated bilayer structures with repeat distances as large as 200 nm. The effect is supposed to originate from attractive bridging forces between polyelectrolyte-covered membranes.