Formulating Novel Halogen-Free Synergistic Flame Retardant Epoxy Resins for Vacuum Assisted Resin Infusion Composites

• 作者: WANG Ming WEI Yi QIU Yiping
• 来源期刊: 东华大学学报（英文版）
• 学科: 工学
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: Textile Reinforced Composites
• 页码范围: 120-127
• 页数: 8页
• 分类号: TQ327.8
• 语种: 英文
• DOI: 10.19884/j.1672-5220.202104016

摘要

The most common process to manufacture advanced composites is the costly autoclave. One of the out-of-autoclave alternatives is the low-cost vacuum assisted resin infusion ( VARI ) which produces quality parts with less pollution. Epoxy resin is a widely used composite matrix resin, but its high flammability limits its use as interior composite parts for vehicles. The usual flame retardant for epoxy involves halogen, which is effective but has high smoke toxicity. As a result, halogen-free flame retardant epoxy resin systems become dominant. In this paper, phosphorus flame retardant was combined with benzoxazine ( BOZ) to produce synergistic effect and achieve satisfactory flame retardance, as well as mechanical improvement for the epoxy resin. Differential scanning calorimetry (DSC), dynamic mechanical analysis ( DMA) , thermal gravitational analysis ( TGA) , the cone calorimeter ( CC) , and limiting oxygen index ( LOI) were used to characterize the resins. The results showed significant improvement on the flame retardance of the synergistically modified resins. Specifically, the carbon residue increased by 113. 6％, and the char thickness increased by 6 to 7 times, compared to those of the flammable benchmark resin. The LOI reached 33 and passed the UL94 V-0 vertical burn rating. The modified resins also exhibited adequate stability and viscosity suitable for VARI processes.