羰基铁粉改性环氧树脂/乙基纤维素微胶囊的吸波性能

以羰基铁粉为吸波剂用溶剂蒸发法制备出环氧树脂/乙基纤维素微胶囊，使用矢量网络分析仪、激光粒度分析仪、ESEM-EDS和FTIR分别表征了微胶囊的吸波性能、粒径分布、颗粒特性以及化学结构。结果表明：羰基铁粉嵌入乙基纤维素中物理结合成微胶囊壁材，羰基铁粉提高了微胶囊的吸波性能。羰基铁粉的粒径越小与电磁波相互作用的面积越大，微胶囊的吸波性能越好。频率为18 GHz时，未掺羰基铁粉的微胶囊电磁波反射损失为-1.63 dB，而掺入粒径为3 μm和0.5 μm羰基铁粉(掺量50%)的微胶囊电磁波反射损失分别为-5.08 dB和-5.44 dB，分别降低了3.45 dB和3.81 dB。掺入粒径为0.5 μm羰基铁粉的微胶囊不团聚，其微观形貌更好。

Wave-Absorption Properties of Epoxy /Ethyl Cellulose Microcapsule Modified by Carbonyl Iron Powder

Carbonyl iron powder was taken as electromagnetic wave absorbent, then the epoxy/ ethyl cellulose microcapsule incorporated with carbonyl iron particles was prepared by means of solvent evaporation. The wave-absorbing property, particle size distribution, characteristics of particle and chemical structure of the microcapsules were characterized by means of vector network analyzer, laser particle size analyzer, ESEM-EDS and FTIR. The result shows that the wall material of the microcapsules consists of carbonyl iron powder and ethyl cellulose, thus the wave-absorption properties of microcapsules incorporated with carbonyl iron powder were reinforced. The smaller carbonyl iron powder has a larger interaction area with electromagnetic waves, therefore, the microcapsules incorporated with smaller particle carbonyl iron particles will exhibit better wave-absorption properties. At 18 GHz, the reflection loss of microcapsules without carbonyl iron particles was -1.63 dB, but the reflection loss of the microcapsules incorporated with 50% carbonyl iron particles can reach -5.08 dB and -5.44 dB for the particle size of 3 μm and 0.5 μm respectively, correspondingly, which are 3.45 dB and 3.81 dB lower than that for microcapsule without carbonyl iron particles, besides, the microcapsules incorporated with 50% carbonyl iron particles of 0.5 μm show excellent dispersibility as well.