Bis(trifluoromethyl)carbinol polynorbornene as a pseudo-polyelectrolyte in multilayered films

Using weak, opposed to strong polyelectrolytes in multilayer polymer systems provides a convenient means of altering some of the physico-chemical properties of these thin films. Recently, we pushed the limits of the weak polyacids by the introduction of an additional class of polyelectrolytes, the pseudo-polyelectrolytes (pPE). This paper focuses on another pPE, poly[5-(2-trifluoromethyl-1,1,1-trifluoro-2-hydroxypropyl)-2-norbornene] (PNBHFA). As, with poly(4-vinylphenol), multilayer assembly with both a weak and a strong polycation was accomplished from aqueous media. However, this was achieved only at a high pH value of 12.0. The films that were produced were exceptionally thick, > 1.25 μm after only 30 total layers for the poly(allylamine hydrochloride)/PNBHFA system. The films were very hydrophobic with the contact angle of water increasing with the layer number; reaching a maximum of ~ 123° after 50 total layers of poly(diallyldimethylammonium chloride)/PNBHFA.