Flame retardant organic polymers have found many applications ranging from aircraft interiors, interior components of rail cars and bus, constructions, and electronic components, etc. However, except for a limited number of so-called inherently flame resistant polymers such as polytetrafluoroethylene (Teflon) and polyvinyl chloride, etc., the commonly used unsaturated polyesters and vinyl esters in composite industries are not generally flame resistance. One most used technique to improve flame retardant is by physically blending flame retardant additives such as Sb_2O_3 in combination of brominated aromatics. The disadvantages associated with physically blended flame retardant additives include compatibility issues, problem of additives leaching out over time, and the fact that the decomposition temperature of the fire retardant needs to be appropriate for a specific polymeric material. In order to avoid the problem of aging, one may add halogens bonded to the backbone of unsaturated polyesters, vinyl esters and epoxy systems. This incorporation has resulted in an increased char yield and higher limiting oxygen index, which is one of the often used measurement methodologies. The disadvantage of halogen based flame retardants is the fact that toxic gases of hydrobromide (HBr) or hydrochloride (HCL) are emitted upon combustion. There is also common belief that switching from styrenated resin system to styrene free or monomer free resin system may further improve the smoke generation and smoke toxicity. The new halogen free and monomer free flame retardant vinyl hybrid resin chemistry was developed by incorporating flame retardant structures into the polymeric backbone. The new resin system has demonstrated excellent fire resistant properties characterized by UL 94 and Cone calorimetry tests. This paper will describe and present the mechanical properties, flame retardant properties and thermal properties of this novel chemistry as compared to standard flame retardant vinyl esters. In addition, this new resin system contains no halogen, no styrene and other monomers, and has extra low VOC (volatile organic compounds) (< 0.8%). This new chemistry also demonstrates excellent catalyzed stability at room temperature and snap cure at elevated temperature.
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