Preparation and properties of bisphenol A-based bisphthalonitrile polymers

The nitrile groups of 2,2-bis [4-(3,4)-dicyanophenoxy phenyl] propane (bisphthalonitrile; BAPh) can be cured by the nucleophilic phenol groups. Bisphenol A (BPA) can react with 4-nitrophathalonitrile to synthesize BAPh. Therefore, BPA was used as a novel curing agent to react with BAPh. The BAPh/BPA prepolymers and polymers were prepared by heat polymerization. The curing behaviors were characterized using differential scanning calorimetry, dynamic rheological analysis, and thermogravimetric analysis. The results indicate that BPA can decrease the melting temperature of BAPh, shorten the curing time of BAPh with lower curing temperature at 243°C, and widen the processing windows of BAPh to 95–120°C. Meanwhile, BAPh/BPA polymers could withstand temperatures up to 443°C under nitrogen atmosphere and 420°C in air when cured at 240°C for 10 h. The mechanical properties of BAPh/BPA polymers were investigated, and it exhibits a flexural strength of 75 to 122 MPa. Dynamic mechanical analysis was used to evaluate the dynamic mechanical properties of BAPh/BPA polymers. The polymers show glass transition temperature ranging from 244 to 299°C heating and cured to 240°C. Herein, the BAPh/BPA polymers can be a good candidate resin for high-performance polymeric materials.