| Resin matrix composite is an excellent functional materials which combine thewave-transparent property and mechanical property. Epoxy resin is one of the mostwidely matrix in the resin matrix wave-transparent composites, which has thecharacteristics of the technology mature, light weight and high strength. However,the dielectric properties and toughness of epoxy resin is poor. These flaws make itreally difficult to meet the requirement of broadband wave-transparent compositematerials. We have modified the epoxy resin to overcome these flaws to get a kindof resin with low viscosity and good dielectric properties. Then the quartz fiber thathas an excellent dielectric performance is used as reinforced material, we haveprepared quartz fiber reinforced modified resin composites. Also we have made adetailed analysis of the research on properties of the composite materials, such aswave transmission properties, dielectric properties, heat resistance performance andmechanical properties.The best curing process of modified epoxy/MeTHPA/DMP-30system is80℃/4h+130℃/4h+150℃/2h, and glass transition temperature of the composites wasabout120℃.The four different ratios of resins （A:B=100:0,95:5,85:15and70:30）canmeet the requirements of the wave-transparent materials on dielectric properties andwave-transparent property. In particular, in the frequency range from0.1GHz to20.01GHz, their dielectric constants and dielectric loss are respectively2.40~2.60and0.003~0.025, while the composite is3.50mm thickness, the transmissionefficiency is over86%. In addition, we have studied the influence of the thicknesson the wave-transparent performance by using electromagnetic field analysissoftware HFSS. The results shows that the thickness variations of the compositesmade from four different proportions of resin, which exert influence on thewave-transparent performances are similar. As the composites is1.00mm thickness,the transmission efficiency is over94%, Even it is over97%when the ratio of resinis A:B=70:30. Moreover, In the frequency range from11GHz to20.01GHz, the5mm thickness of composites is better than the3.50mm thickness of composites on the transmission efficiency. By testing the dielectric properties of composite madefrom A：B=70:30at the end of each ageing cycle, We have studied the experimentresult and have known that the dielectric constants decreased and then increase withthe increasing of aging cycle, but the dielectric loss changes is no rules to follow.Besides, the effect of hydrothermal ageing on the dielectric properties of compositesis more obvious than ultraviolet radiation.The four different ratios of resins can meet the requirements of thewave-transparent materials on mechanical properties. When the proportion of A andB is70:30, its impact toughness is382KJ/m2, it had played the function oftoughening （while A:B=100:0,its impact toughness is341KJ/m2）. The effects ofultraviolet radiation and hydrothermal ageing on the properties of composites werestudied. The composites are processed by four aging cycle, the experiment resultsshow that the composites made from the four different ratios of resins have excellentageing resistance. the ratios of resin are A:B=100:0and95:5, the flexural modulusdecrease insignificantly, but, A:B=85:15and A:B=70:30, the flexural modulusincrease slightly.B component content is less than30%, wave-transparent property andmechanical properties are good. And when A:B=70:30, the impact toughness andwave-transparent are the most excellent performance. |
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