The status and the variation of electrical resistance of impacted carbon fiber/epoxy-matrix composites were studied by ultrasonic F-scan and electrical resistance measurement The experimental results shows that impact...The status and the variation of electrical resistance of impacted carbon fiber/epoxy-matrix composites were studied by ultrasonic F-scan and electrical resistance measurement The experimental results shows that impact damage energy threshold value of carbon fabric/epoxy-matrix composites can determine by using ultrasonic F-scan. When the impact energy exceeds the threshold value, damage is generated in composites. Electrical resistance of impacted composites is changed owing to the contact of each carbon fiber unit in composites, which cause a change of the series-parallel in conductors. The veracity of detecting impact damage in composites can be improved in this case.展开更多
以1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(DSX)和环氧氯丙烷(ECH)为原料,利用相转移催化剂,合成双酚F环氧树脂(BPFER)改性剂N,N,N′,N′-四缩水甘油基-1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(TG-siloxane),并用FTIR、13 C NMR谱图对其结...以1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(DSX)和环氧氯丙烷(ECH)为原料,利用相转移催化剂,合成双酚F环氧树脂(BPFER)改性剂N,N,N′,N′-四缩水甘油基-1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(TG-siloxane),并用FTIR、13 C NMR谱图对其结构进行了表征。对TG-siloxane改性BPFER/mXDA(间苯二甲胺)体系的固化动力学进行了研究。根据DSC曲线和Starink方程,得该体系表观固化活化能为51.52kJ.mol-1。用esták-Berggren模型求得不同升温速率下的表观因子、反应级数。动力学方程表明,升温速率对固化反应影响明显;所得方程用于预估反应进程时,与实测值吻合程度高。TG分析表明,TG-siloxane改性BPFER/mXDA体系固化物的耐热性能优于单纯BPFER/mXDA固化物。展开更多
基金Funded by the Key Laboratory of Nondestructive Testing (Nanchang Hangkong University), Ministry of Education, China(No.ZD200829001)
文摘The status and the variation of electrical resistance of impacted carbon fiber/epoxy-matrix composites were studied by ultrasonic F-scan and electrical resistance measurement The experimental results shows that impact damage energy threshold value of carbon fabric/epoxy-matrix composites can determine by using ultrasonic F-scan. When the impact energy exceeds the threshold value, damage is generated in composites. Electrical resistance of impacted composites is changed owing to the contact of each carbon fiber unit in composites, which cause a change of the series-parallel in conductors. The veracity of detecting impact damage in composites can be improved in this case.
文摘以1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(DSX)和环氧氯丙烷(ECH)为原料,利用相转移催化剂,合成双酚F环氧树脂(BPFER)改性剂N,N,N′,N′-四缩水甘油基-1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(TG-siloxane),并用FTIR、13 C NMR谱图对其结构进行了表征。对TG-siloxane改性BPFER/mXDA(间苯二甲胺)体系的固化动力学进行了研究。根据DSC曲线和Starink方程,得该体系表观固化活化能为51.52kJ.mol-1。用esták-Berggren模型求得不同升温速率下的表观因子、反应级数。动力学方程表明,升温速率对固化反应影响明显;所得方程用于预估反应进程时,与实测值吻合程度高。TG分析表明,TG-siloxane改性BPFER/mXDA体系固化物的耐热性能优于单纯BPFER/mXDA固化物。
