Flammability of benzoxazine resin based carbon fibre composite samples

Abstract

The present paper is dealing with the flammability characteristics of a composite system manufactured with hybrid benzoxazine resin and carbon fibre. Benzoxazine thermoset resin can polymerize on heating to 200℃ to give a good thermal resistance, high mechanical strength properties and good processability with nil volatiles and near-zero volume change during cure. Benzoxazine resin possesses excellent flammability behavior which is similar to phenolic resins due to its nature of formation of a comparable network after polymerization. Samples were made using bi-directional 2x2 twill of 200 GSM carbon fibres with Anabond®Anazine 1951 hot cured hybrid benzoxazine monomer resin. Samples were cut and tested as per UL94 vertical burning standard using a Bunsen burner apparatus. It is observed from the test results that the samples can extinguish fire within 3 seconds after first flame application and 4 seconds after second flame application; this fulfills the requirement for UL94 V0 fire retardancy classification which is the mandated requirement for the composite materials used in spacecraft and aerospace applications.