CB/PBO复合材料制备及吸波性能研究

以4, 6二氨基间苯二酚盐酸盐(DAR?2HCl)、对苯二甲酸(TPA)为原料, 合成TA盐, 再缩聚制得具有较高耐热性的聚对苯撑苯并二噁唑(PBO)。以PBO为基体, 炭黑(CB)为吸收剂, 热压法制备CB/PBO复合材料。对不同炭黑质量分数的复合材料介电及PBO基体与复合材料的热性能进行研究。结果表明, 随着炭黑含量的增加, 材料的复介电常数的实部与虚部均增大。含5%炭黑的试样厚度达到2 mm时, 吸波性能最好, 反射率小于-10 dB的带宽可达2.4 GHz, 最小反射率可达-32 dB。在空气中450℃保温5 h, PBO的质量损失为11.84%, 而5% CB/PBO复合材料的质量损失为21.99%。

Preparation and Microwave Absorption Properties of CB/PBO Composite

TA salt was prepared by the solution of 4,6-diaminon1,3-benzenediol and terephthalic acid, and then copolymerized in PPA to get poly(p-phenylene benzobisoxazole) (PBO) with good thermal resistance. Using as-prepared PBO as matrix, carbon black (CB) as absorber, CB/PBO composites were fabricated by hot pressing. Influences of CB weight concentration on complex permitivity and on thermal properties of CB/PBO composites were investigated. The results show that the real and imaginary parts of permittivity are increased with the increase of carbon black concentration. The reflectivity bandwidth and reflection loss lower than -10 dB are about 2.4 GHz and -32 dB, respectively, when CB weight concentration is 5% and the thickness of composite is 2 mm. The mass loss of PBO and CB/PBO composite are 11.84% and 21.99%, respectively, when kept at 450℃ for 5 h.