Photochemical preparation of polymer-clay composites

Polymer–clay composites of poly([2-(methacryloxy)ethyl]trimethylammonium chloride) and various clayey minerals have been prepared by visible light-induced free radical polymerization. The starting monomer–clay formulation contained: (i) the initiating dye, Rose bengal derivative, (2′[6-(3-trimethylaminopropoxy)-2,4-diiodo-3-oxo-3H-xanthen-9-yl]-benzyloxy-propyltrimethyl-ammonium dibromide, DBEE); (ii) the electron donor, 2-(dimethyl-amino)ethyl methacrylate; and (iii) the crosslinking monomer, poly(ethylene glycol) dimethacrylate. The method allows to prepare 1–2 mm thick foils that can be formed under both artificial lights and the sunlight exposition. The foil is flexible and insoluble in water. The clay is not rinsed out from the composite even after hundreds of hours of water treatment. The obtained composites do not exhibit good mechanical properties.