材料期刊网

为对比分析不同超临界流体对碳纤维/环氧树脂(CF/EP)复合材料的降解效果，首先，在间歇反应釜中通过超临界流体降解CF/EP复合材料，分析了不同反应温度下超临界 CO2和超临界醇对 CF/EP 复合材料的降解能力，并提出了降解CF/EP复合材料的超临界流体选择方法；然后，采用单丝拉伸测试、SEM以及原子力显微镜等测试手段分析了超临界正丙醇和超临界正丁醇回收碳纤维的力学性能和微观形貌。结果表明：超临界 CO2对CF/EP复合材料的降解能力较弱，正丙醇作为夹带剂时，降解效果有显著提高；超临界正丁醇对 CF/EP 复合材料的降解能力最强，其次为超临界正丙醇，超临界甲醇的降解能力最弱；选用的反应介质介电常数越小、偶极矩越大、溶解度参数与树脂基体越为接近，在超临界状态下CF/EP复合材料越容易降解。使用超临界流体降解 CF/EP复合材料可以得到性能优异的碳纤维，与原始碳纤维相比，通过超临界正丙醇和超临界正丁醇回收的碳纤维单丝拉伸强度保持率在98%以上，且韦氏模数相近。

In order to compare and analyze the degradation effects of different supercritical fluids on carbon fiber/epoxy (CF/EP)composites,CF/EP composites were degraded by supercritical fluids in batch reactor firstly,the degradation capabilities of supercritical CO2 and supercritical alcohols at different reaction temperatures for CF/EP composites were analyzed,and the select method of supercritical fluid for the degradation of CF/EP composites was proposed.Then,the mechanical properties and microstructures of carbon fibers recycled using supercritical n-buta-nol and supercritical n-propanol were analyzed by testing measures such as single filament tensile tests,SEM and atomic force microscope etc.The results show that the degradation capability of supercritical CO2 for CF/EP com-posites is weaker,and the degradation capability has significant improvement when using n-propanol as the entrai-ner.Supercritical n-butanol has the strongest degradation capability for CF/EP composites,followed by supercritical n-propanol,and the degradation capability of supercritical methanol is the weakest.The smaller the dielectric con-stant of selected reaction medium is,the greater the dipole moment is,the closer the solubility parameters with the epoxy matrix is,the easier for the degradation of CF/EP composites under supercritical conditions.Carbon fibers with excellent performances could be obtained by degradation of CF/EP composites using supercritical fluids.Com-paring with the original fibers,the retention rates for single filament tensile strength of supercritical n-butanol and supercritical n-propanol recycled carbon fibers are above 98%,and the Weibull modulus are close.