Greatly enhanced mechanical properties and liquid oxygen compatibility of carbon fiber/epoxy composites for liquid oxygen cryotanks by one phosphorus-nitrogen flame retardant

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 2023-03, Vol.166, p.107374, Article 107374
• Main Authors: Long, Jun-Fei, Qian, Jian, Wang, Tong-Tong, Tan, Di, Zhou, Zi-Li, Wu, Tao, Li, Yuan-Qing, Fu, Shao-Yun
• Format: Article
• Language: English
• Subjects: A. Carbon fibre; A. Polymer-matrix composite; B. Flame/fire retardancy; B. Mechanical property
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2022.107374

Carbon fiber reinforced epoxy composites (CFRECs) with excellent liquid oxygen (LOX) compatibility and superior mechanical properties are highly desirable for developing LOX composite cryotanks. Here, firstly, the influences of phosphorus-nitrogen flame retardant (i.e. a bi-group compound (TAD)) on the mechanical, thermal and LOX compatibility performances of epoxy (EP) resin are systematically investigated, and an optimal formulation of TAD modified epoxy resin (15TAD-EP with 15 phr TAD) is proposed. Secondly, the CFREC based on the 15TAD-EP was manufactured via hot press process and is systematically studied with their mechanical properties and LOX compatibility. Interestingly, the flexural strength, flexural modulus, interlaminar shear strength and GIIC of the CFREC at room temperature (RT) and 90 K are all greatly enhanced due to the improvement of interfacial adhesion by the addition of TAD. And the twenty samples of the composite all pass the LOX impact test, showing their excellent LOX compatibility.