Innovative Solutions To Enhance The Flame Retardancy Properties Of Natural And Synthetic Fabrics: Sol-Gel, Dual-Cure Processes And Layer By Layer Assembly

Nowadays, nanotechnology has a real and great potential in the textile industry, considering that conventional methods used to give different properties to fabric textiles often do not lead to permanent effects against wearing or laundering; in such scenario, the use of nanotechnology has been proved to give high durability for fabrics, improve the performance of fibres and create unprecedented functions [1]. The idea is to develop a new method based on the introduction of nanoparticles during the finishing step. Multilayered thin films made of nano size layers, with total thickness ranging from submicron to a few millimetres, can be prepared with a new technique called layer-by-layer (LbL). Now, the technique can be tailored to multimaterial assembly of several compounds without special chemical modifications, thus enabling the production of multilayer films. Furthermore, the technique is very easy and applicable to different field applications, such as textile sector. It consists in an alternate immersion or more simply in alternate spraying of the substrate with an oppositely charged polyelectrolyte solutions, thus creating a structure of positively and negatively charged layers piled up on the substrate surface. On the other hand, the nano-sized particles have been synthesized by sol-gel process, which involves inorganic precursors (organo-silicates, -titanates-aluminates, etc.) that undergo several reactions resulting in the formation of a three-dimensional molecular network. The sol-gel process is conducted at a low temperature which also enables the incorporation of organic compounds into the inorganic structure without decomposition. [1] J. Alongi, F. Carosio, R.A. Horrocks, G. Malucelli. Flame Retardant Textiles: State of the Art, Environmental Issues and Innovative Solutions, Rapra, In press.