Abstract: To achieve efficient thermal insulation of carbon fiber composites,a porous structure system was constructed through the solvent-induced phase separation strategy using T300 carbon fiber prepregs as the reinforcement and epoxy resin as the matrix.Isopropyl alcohol was used as the pore-forming agent and the gradient design of the porosity in the carbon fiber composites was achieved by regulating its additions (0,10%,20% and 30%,by mass).The coupling mechanism of the pore structure evolution on the mechanical and thermal insulation properties of the materials was explored.The results show that:as the isopropyl alcohol addition increases from 0 to 30%,the porosity of the composites increases from 0.71% to 2.14%,accompanied by an increase in the pore number and size,the pore morphology evolves from point-like defects to circular defects,while the mechanical properties show a controllable degradation trend;meanwhile,the thermal insulation performance shows a gradually increasing trend.When the isopropyl alcohol addition is 10%,the material exhibits a porosity of 1.12%,achieving the minimal reduction in the mechanical properties and relatively optimal thermal insulation performance.

Key words: carbon fiber composites, microstructure, mechanical properties, thermal insulation performance

摘要： 为实现碳纤维复合材料的高效隔热,以T300碳纤维预浸布为增强体,环氧树脂为基体,通过溶剂诱导相分离策略构建多孔结构体系。采用异丙醇作为造孔剂,通过调控异丙醇的添加量(质量分数分别为0、10%、20%和30%)实现碳纤维复合材料孔隙率的梯度化设计,探究孔隙结构演化对材料力学与隔热性能的耦合作用机制。结果表明:随着异丙醇添加量从0增加至30%(w),复合材料孔隙率从0.71%提升至 2.14%,孔隙数量递增且孔隙尺寸扩增,孔隙形貌由点状缺陷转变为圆形缺陷,但力学性能呈现可控性衰减趋势;随着异丙醇添加量从0增加至30%(w),材料的隔热性能呈现逐渐上升的趋势;当异丙醇添加量为10%(w)时,材料的孔隙率为1.12%,材料的力学性能降低程度最小,且隔热性能相对最佳。

关键词: 碳纤维复合材料, 显微结构, 力学性能, 隔热性能