抽油杆用CF/VE拉挤复合材料在盐溶液中的老化机理

文中研究了95℃盐溶液(3%NaCl水溶液)中油田抽油杆用碳纤维/乙烯基酯树脂(CF/VE)单向拉挤复合材料的吸湿特性,以及材料的静态力学性能和动态热机械性能的变化,并用SEM观察了弯曲断口形貌。结果表明,该复合材料的吸湿行为符合菲克第二定律,材料的平衡吸湿率Mm 约为0.778%,水分在该复合材料中的扩散系数约为4.988×10^-6mm²/s;复合材料的性能下降趋势与吸湿率的增加趋势相对应,浸泡1176h后 ,弯曲强度和层间剪切强度的最终保留率分别约为63%和66%;DMTA及SEM结果表明,复合材料的性能变化是由基体溶胀塑化、界面脱粘以及基体、界面的形貌变化引起的,未发生化学反应

Aging mechanisim of pultruded carbon fiber/vinylester resin composite used for sucker rods in brine solution

The absorption characteristics, the changes in the static mechanical properties and dynamic mechanical thermal properties of the pultruded carbon fiber /vinyl ester (CF/VE) composite, which was used for sucker rod in oil field, were studied as it was immersed in 3% NaCl aqueous solution at 95℃. The results show that the composite obeys the Fick's second law in terms of absorption behavior, having an equilibrium moisture content about 0.778% and a diffusion coefficient of the order of 4.988×10^-6mm²/s, and a decrease in the properties of the composite is very relative to the increase in its moisture content. After the composite had been immersed for 1 176 hours, its interlaminar shear strength and flexural strength had a reservation about 63% and 66%, respec-tively. The results of dynamic mechanical thermal analysis (DMTA) and SEM show that changes in properties are caused by swell and plasticization of matrix, interfacial debonding and the microstructure changes of matrix and interface. No chemical changes are found.