Chapter 16 - Flame-Retardant Thermoset Nanocomposites for Engineering Applications

Abstract

Thermosets such as epoxy, unsaturated polyester, acrylic, and vinyl ester resins are commonly used for rigid fiber-reinforced composites. The flammability of polymeric resins has always been a great concern, limiting their use in applications where fire safety is a key criterion. The chemical modification of the resin and the use of conventional flame retardants (FRs) are common methods of rendering them flame retardant. However, the addition of high concentrations of additive and sometimes reactive flame retardants in a polymeric system often causes significant deterioration of the mechanical properties of the material. Environmental concerns have also been raised regarding the production of toxic gases during burning of certain flame-retarded resins. On the other hand, polymer nanocomposites have attracted considerable attention for last two decades by offering good mechanical, thermal, and fire-retardant properties to polymers, while being incorporated in polymers at very low concentrations (2–5wt% as opposed to >15% of conventional FRs). This chapter discusses the variety of nanoparticles that have been used as flame retardants, alone or with conventional flame retardants in last 20 years in thermoset resins and fiber-reinforced composites. The challenges posed for the successful commercial exploitation of thermoset nanocomposite resins are also outlined.