Influence of flame retardants on the mechanical properties of glass fiber reinforced compounds in polymeric matrix epoxy and polyester

In the present study, polymeric epoxy and polyester resin reinforced with glass fiber compounds were prepared by adding of flame retardants based on aluminum and magnesium hydroxide in order to evaluate their influence on mechanical properties. An experimental DOE design was developed with two qualitative factors: the resin and retardant type; with two levels each and a quantitative factor: volumetric composition of the retardant with three levels (3%, 6% and 9%). With all possible combinations; tensile, flexural and impact tests were carried out. The results showed that the addition of retardants in different percentages has different influence for each mechanical property. It was evidenced that the 9% HA Aluminum Hydroxide has no significant effect on the tensile strength and its modulus compared to Magnesium Hydroxide HM. Conversely; on the flexural strength, flexural modulus and rupture energy the HM has a slightly lower effect with respect to the HA. For flexural strength and its modulus, the best proportion of retardant was 6%. 3% is the recommendation for rupture energy. The data presented in this document can be used to improve the fire resistance of the existing materials studied. (paper)