Phthalonitrile resin PN-3М (PN-CF)

Structures requiring high heat resistance;Parts requiring non-combustibility;Parts of engines and other special applications;High temperature tooling for thermoplastics

Samples for testing were obtained by vacuum infusion based on PN-3M resin and carbon fabric 22502 (twill 2x2, 200 g/m2, HTA40-3K, 3.95 GPa).

Assemble the vacuum bag. Perform a leak test, the rate of the vacuum drop should not be more than 1 mbar per minute. The residual pressure in the bag must not be more than 10 mbar. Assemble the second vacuum bag, put airweave material between the layers of the vacuum film. Perform a leak test for the second vacuum bag. The residual pressure in the bag must not be more than 10 mbar. Degas for 30-40 minutes, at 150-160°C, at a pressure of no more than 10 mbar. During the degassing, the resin should be stirred intensively. Heat the tool up to 150-170°C. Maintaining the temperature of resin dispenser at 160°C, start the infusion process. After complete impregnation of the bag, close the resin inputs, but continue evacuation from the inner bag for at least 30 minutes. Then close the outputs from the inner bag. Maintain the outer vacuum bag until the end of curing process. Increase the temperature at a rate of 2°C/min to 180°C. Dwell at 180°C for 6 hours. Before removing the part, cool the mold to at least 60°C at a speed of no more than 5°C/min. Post-cure can be performed without tooling. Heat to 180°C at a rate of 2°C/min, then heat to 375°C at a rate of 5-10°C/min. Dwell at 375°C for 8 hours. Cool down the part to 60°C at rate <5°C/min. For the measurement of vacuum, the use of absolute pressure sensors is recommended.