空气等离子体炬改性连续玻纤束的工艺研究

Process of modification of continuous glass fibers using an air plasma torch

玻璃纤维表面光滑且呈化学惰性,聚丙烯缺少极性官能团,导致玻璃纤维与聚丙烯之间的界面润湿性能较差。为了提升玻璃纤维增强聚丙烯(GFRP)复合材料的界面结合性能,设计并搭建了空气等离子体炬处理装置,通过该装置在连续玻璃纤维束表面沉积SiO纳米颗粒,并测定了改性玻璃纤维的润湿性能和GFRP复合材料的界面剪切强度;采用响应曲面法(RSM)分析了喷嘴与纤维间的距离、载气流量、处理时间对玻璃纤维润湿性能的影响,并对这些工艺参数进行了优化。结果表明:当处理距离为20 mm、载气流量为1.5 L/min、处理时间为6 s时,与对照组相比,改性后的玻璃纤维与聚丙烯的接触角降低了49.8%,GFRP复合材料的界面剪切强度提高了94.7%;载气流量对玻璃纤维润湿性能的影响程度最大,处理时间次之,处理距离的影响最小。优化后的工艺参数为:喷嘴与纤维间的距离为18 mm,载气流量为1.7 L/min,处理时间为7 s。在此工艺条件下制备了空气等离子体炬改性的玻璃纤维,实测的接触角(24.6°)与预测值(25.0°)之间的偏差仅为1.6%。

The surface of a glass fiber is smooth and chemically inert,and polypropylene lacks polar functional groups,resulting in poor interfacial wettability between glass fibers and polypropylene.In order to improve the interfacial bonding properties of glass fiber reinforced polypropylene(GFRP)composites,an air plasma torch treatment device was constructed and used to deposit SiOnanoparticles on the surface of continuous glass fiber bundles.The wettability of the modified glass fibers and the interfacial shear strengths of the GFRP composites were measured.The effects of varying the distance between the nozzle and fiber,carrier gas flow rate and treatment time on the wettability of glass fibers were analyzed by response surface methodology(RSM),and the process parameters were optimized.When the treatment distance was 20 mm,the carrier gas flow rate was 1.5 L/min,and the treatment time was 6 s,the contact angle between the modified glass fiber and polypropylene decreased by 49.8%,and the interfacial shear strength of the GFRP composite increased by 94.7%compared with the control group.The influence of carrier gas flow rate on the wettability of glass fibers is the greatest,followed by treatment time,whilst the influence of treatment distance is the least significant.The optimized process parameters are as follows:a distance between the nozzle and fiber of 18 mm,a carrier gas flow rate of 1.7 L/min,and a treatment time of 7 s.Glass fibers modified using the air plasma torch were prepared under the optimized process conditions,and the deviation between the measured contact angle(24.6°)and the predicted value(25.0°)was only 1.6%.