There is provided a method of treating textile fibres including: a) providing a polymeric precursor including a diallyl amide cationic compound and a corresponding counter ion; b) either (i) coating the textile fibres with the polymeric precursor and polymerising the polymeric precursor to form a polymeric coating, or (ii) polymerising the polymeric precursor and contacting the polymerised polymeric precursor with the textile fibres to form a polymeric coating on the textile fibres. There is also provided a composite structure including a polymeric coating formed from the polymeric precursors of the present invention.