乳液聚合条件对纳米Fe3O4／导电聚苯胺磁导率的影响

Effect of Emulsion Polymerization Conditions on Permeabilities of Fe_3O_4/Conductive Polyaniline Nanoparticles

以十二烷基苯磺酸(DBSA)为乳化剂和掺杂剂,过硫酸铵(APS)为氧化剂,采用乳液聚合的方法合成了导电聚苯胺包覆磁性四氧化三铁的纳米核-壳复合材料。利用3cm波导式测量线法分别研究了聚合反应中Fe3O4,DBSA和APS与苯胺的相对含量对复合材料磁导率(μ′,μ″)的影响。测量结果表明,Fe3O4的加入能够显著提高材料的磁损耗,扩展吸收频带;DBSA和APS的加入主要对聚苯胺的共轭结构和导电性产生影响,对磁损耗的改变比较小,但是其过量的加入将会增加复合材料中的界面原子数和电偶极子的含量等,从而使复合材料的磁导率产生波动性变化。

Electrically conducting polyaniline （PANI） -magnetic oxide （Fe3O4） composites with electrical and ferromagnetic behaviors were synthesized by the way of emulsion polymerization in the presence of dodecyl benzene sulfonic acid （DBSA） as a surfactant and dopant and ammonium persulfate （APS） as the oxidant. The permeabilities of Fe3O4/DBSA -PANI nanocomposites with core-shell structure were studied by varying the contents of Fe3O4, DBSA and APS. The results show that the Fe3O4 can improve the magnetic loss of the composites remarkably and widen the absorbing wave band. The contents of DBSA and APS have the less influence on the permeabilities of the composites because they mostly influence the conjugated structures and conductivities of the PANI, but the excessive DBSA and APS will increase the number of interfacial atoms and dipoles in the composites and therefore make the permeability have a fluctuant change. The different dissipative mechanisms were discussed to explain the varieties.