PHOSPHORUS-CONTAINING PHTHALONITRILE RESIN FOR VIMP AND RTM PROCESSING.

New phthalonitrile resin formulation based on the low-melting phosphorus-containing monomer bis(3-(3,4-dicyanophenoxy)phenyl) phenyl phosphate recently reported by our research group, common phthalonitrile 1,3-bis (3,4-dicyanophenoxy)benzene and aromatic diamine as curing agent was developed. The resin processing properties (melt viscosity 150 mPa⋅s at 150°C) allowed to produce carbon fiber composites by vacuum infusion molding process and resin transfer molding at 150 °C. The curing cycle consisting of 3 hours at 180 °C and post-curing at 375 °C was required to achieve the best thermal properties. After post-curing the obtained composites demonstrated up to 90 % mechanical properties retention at 400 °C (τr.t.12 = 60-80 MPa). Flame retardant properties were investigated and the composites demonstrated extremely high LOI > 80 %. Thus easily processable phthalonitriles with quick curing and excellent heat resistant and flame retardant properties were developed. [ABSTRACT FROM AUTHOR]