金属离子掺杂对皮胶原纤维基吸波剂的雷达吸波性能影响

Effects of metal ions doping on rader waves absorption performances of collagen fiber based waves absorbents

将皮胶原纤维(CF)与水杨醛(Sa)反应,获得含有席夫碱结构(CN)的胶原纤维(Sa-CF),再进一步用Fe3+、Mn2+、Co2+、Cu2+和Zn2+过渡金属离子对Sa-CF进行"掺杂",制备了具有雷达波吸收性能的皮胶原纤维(M-Sa-CF)。分别将CF、Sa-CF和M-Sa-CF压制成膜,采用探针法对其电导率进行测定,利用弓形法测定其对雷达波(频率0.5～18.0GHz)的反射损失(RL)。结果表明,CF的电导率仅为1.08×10-9 S/cm,而Sa-CF电导率可提高3个数量级,达到2.86×10-6S/cm;再经金属离子掺杂后其电导率进一步提高,如Zn2+掺杂后的电导率达到8.37×10-4S/cm。Sa-CF和M-Sa-CF的吸波机理为电损耗型,Sa-CF经金属离子掺杂后,电导率提高,对雷达波的反射损失增强,但不同金属离子掺杂后反射损失增加的幅度不同,Sa-CF雷达波反射损失在8.8GHz处最高为7.57dB,经Cu2+掺杂后雷达波反射损失在8.29GHz处最高达到8.35dB,而经过Fe3+掺杂后雷达波反射损失在8.11GHz处最大可达14.68dB。采用Fe3+、Mn2+和Zn2+具有半满壳和全满壳电子构型的金属离子掺杂,对雷达波的反射损失可大幅度提高,且吸收频段加宽。另外,掺杂量不同,最大反射损失和最大反射损失所处的频率均发生了变化。

Using skin collagen fiber（CF） as raw material,Schiff base structure contained CF（Sa-CF） was synthesized through CF-salicylaldehyde reaction,then metal ions,including Fe3＋,Mn2＋,Co2＋,Cu2＋ and Zn2＋ were doped in Sa-CF to make M-Sa-CF radar waves absorbents.Sa-CF and M-Sa-CF were pressed and membranes were obtained.The probe method was used to determine conductivity of Sa-CF and M-Sa-CF membranes,and the arch measurement method was used to investigate their radar waves reflectance loss（RL） in the frequency range of 0.5-18.0GHz.Experimental results indicated that the conductivity of CF was significantly increased three orders of magnitude after reacted with salicylaldehyde,and further increased after doping with metal ions.It was found that the conductivity of Zn2＋ doped Sa-CF was 8.37×10-4S/cm.The electric-loss is the radar waves absorption mechanism of Sa-CF and M-Sa-CF.The conductivity of Sa-CF is increased after doped with metal ions,and therefore their absorbing strength are also increased.However,the radar waves reflectance loss（RL） of M-Sa-CF is quite different when doped with different metal ions.The greatest RL of Fe-Sa-CF was 14.68dB at 8.29GHz,while Cu-Sa-CF was only 8.35dB at 8.29GHz.It was found that the RL and frequency bandwidth of M-Sa-CF were greatly enhanced and widened respectively when doped with Fe3＋,Mn2＋ and Zn2＋,which have the electronic configuration of half-full-shell and full-full-shell.With different dosage of doping,the greatest RL and its frequency location were also changed.