Poly(phenylene oxide) modified cyanate resin for self-healing Li Yuan1/2/3/4*, Sidi Huang3, Yinhui Hu3, Yuzheng Zhang3, Aijuan Gu4, Guozheng Liang4, Guoqiang Chen1, Yongming Gao2, Steven Nutt3** 1. L. Yuan, G. Chen, College of Textile and Clothing Engineering, Soochow University, Suzhou, Jiangsu, 215123, China 2. L. Yuan, Y. Gao, Jiangsu Yingxiang Chemical Fiber Stock Co., Ltd, Wujiang 215228, China 3. L. Yuan, S. Huang, Y. Hu, Y. Zhang, S. Nutt, Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA, 90089, USA 4. L. Yuan, A. Gu, G. Liang, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering, and Materials Science, Soochow University, Suzhou, Jiangsu, 215123, China * Correspondence to: Li Yuan, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, China. E-mail:
[email protected] ** Correspondence to: Steven Nutt, Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089, USA. E-mail:
[email protected] Abstract: Self-healing cyanate ester resins (CE) were developed by adding low molecular weight poly(phenylene oxide) (PPO) resin, yielding a high performance CE/PPO system via a low- temperature process. The addition of PPO improved the flexural strength and fracture toughness of the CE matrix without sacrificing thermal properties. CE/PPO formulations with 5, 10, and 15 wt.% PPO showed 43%, 65%, and 105% increase in fracture toughness due to a combination of crack deflection, crack pinning, and matrix cavitation around second-phase particles.