Toughening effect of poly (arylene ether nitrile) on phthalonitrile resin and fiber reinforced composites.

A strategy for toughening phthalonitrile-based resin containing benzoxazine (BA-Ph) with poly (aryl ether nitrile) (PP-PEN) was proposed. Through kinetic analysis, the underlying influence mechanism of PP-PEN with different molecular weight on the polymerization process and cross-linking structure of BA-Ph was explored. In addition, the glass fiber reinforced composite laminates (BA-Ph/PP-PEN/GF) were fabricated by hot pressing. The effect of the molecular weight of PP-PEN on the mechanical and thermal properties of BA-Ph/PP-PEN/GF was verified. The results indicated that the impact strength of the modified composite laminates increased from 77 kJ/m2 to 106 kJ/m2. The bending strength and modulus improved from 484 to 516 MPa and 21 GPa to 25 GPa, respectively. Besides, all the thermal performances of the modified composite laminates had fairly good thermal stability (358 ~ 382 °C). It is believed that the as-prepared phthalonitrile-based composite material with high temperature resistance and toughness is expected to expand the application of high-performance resin based composites. [ABSTRACT FROM AUTHOR]