Influence of temperature on tensile deformation and fracture of unfilled and short-glass-fiber filled poly(cyano aryl ether)

Tensile deformation and fracture of injection-molded poly(cyano aryl ether) thermoplastic (UR-PCAE) and its short-glass-fiber reinforced composite (SGF-PCAE) were studied with particular attention to the effect of testing temperature T. PCAE exhibited high performance in stiffness and thermal resistance in the dynamic mechanical analysis. The tensile strength for UR-PCAE specimens was decreased to about a half with an increase of T from - 40° C to 100° C. SGF-PCAE exhibited brittle-like fracture in the temperature range stated above, and a large decrease in failure strain and strain energy ductility index. Compact tension type specimens showed low fracture toughness Jt: UR-PCAE provided a minimum value at 60°C, but a large increase in Jt with a further increase in T. For SGF-PCAE, however, Jt showed a slight increase from 23°C to 100°C. Fracture surface observation revealed that the matrix ductility considerably affected the dependence of T on the toughness.