Liquid oxygen compatibility of epoxy matrix and carbon fiber reinforced epoxy composite. (March 2022) - Li, Shichao
Highlights: A novel additive DOPO-PGE was prepared by the polymerization reaction between P-H bond and epoxy group. DOPO-PGE can enhance the liquid oxygen compatibility of epoxy resin and carbon fiber reinforced epoxy composite. The mechanism of DOPO-PGE enhancing the liquid oxygen compatibility of epoxy resin and composite was analyzed in detail. Long-term liquid oxygen immersion will affect the liquid oxygen compatibility of carbon fiber reinforced epoxy composite. Abstract: Liquid oxygen compatibility is the key to evaluating whether carbon fiber reinforced epoxy composites (CF-composite) can be used in liquid oxygen environment. In this work, DOPO-PGE was prepared to improve the liquid oxygen compatibility of epoxy resin and CF-composite. The FTIR, 1 H and 31 P NMR spectrum was used to confirm the chemical structure of DOPO-PGE. According to the UL94 test results, TG-FTIR, char residue analysis, and XPS analysis, the mechanism of DOPO-PGE affecting the liquid oxygen compatibility of epoxy resin is mainly attributed to the fact that the radical PO released in the initial thermal decomposition stage of DOPO-PGE/epoxy can capture the highly active radical H, O, HO and terminated the radicals' chain exothermic reactions. The CF-composites show better liquid oxygen compatibility than epoxy resin matrix. However, the long-term liquid oxygen immersion can deteriorate the liquid oxygen compatibility of CF-composites.