Thermal degradation of polymers. VIII. Ablation studies on a series of fiber-reinforced phenolic resin composites

The use of a laboratory ablation test rig for the assessment of tubular fiber‐reinforced composites is described. Ablation resistance, char depth, smoke, and flash measurements have been made on a series of composites based on a standard phenol–formaldehyde resin incorporating various fibrous reinforcing agents. The results have been compared with those obtained from a standard asbestos‐reinforced composite prepared from the same resin. Results are discussed in terms of the properties of the composite and of the fibrous reinforcing agent.