Research Of Conductive Composites Vulcanizated Aided With External Field Induction

With the rapid growing of modern science and technology, our life has been strongly affected by electromagnetic interference. Electromagnetic shielding materials have been received more and more widespread attention. As excellent electromagnetic shielding materials, conductive composites have been used widely in electronics, communication and construction. Because of higher and higher requirement of shielding material, their development tends to be more smart and efficient. As an effective way to improve the shielding smart material, ordering structure has become an important direction in the research of conductive composites.On the basis of the traditional preparation of conductive silicon rubbers(CSRs), this project sets up the vulcanized experiment platform with two different induction external fields and introduced the technology of inducing external fields. With CSRs vulcanization, nickel-coated carbon fiber, nickel-coated graphite, nickel-coated aluminum, nickel carbonyl have been arranged orderly by induction external fields. Accordingly, the purpose of this paper can be achieved that make shielding materials structure orderly. Based on the assessment of electrical properties and mechanical properties of CSRs, this study tries to investigate the mechanism of induction external fields for conductive particles in the CSRs.In the experiments of CSRs vulcanization, the experiment platform of single and double magnet induced vulcanization without heating and the experiment platform of magnet field induced vulcanization with heating have been established. The results show that conductive particles in the CSRs are obviously effected by magnetic fields. And the resistivity of CSRs decreased significantly by conductive particles’ orderly arrangement, which reduced 10 orders of magnitude at most. The shielding effectiveness(SE) of CSRs improved significantly too. In addition, the mechanical properties of CSRs is related to the morphology and size of conductive particles. In addition, with the influence of vulcanization by induction magnetic fields, the resistivities of CSRs present different results in different directions of measurement, which can be up to more than one order of magnitude. This is the characteristics of anisotropy.Three sets-up of induction electric field with different voltage including 30 V DC, 220 V AC and AC high-voltage have been built to assist particle orientation in the vulcanization of conductive composites. Unfortunately, the conductive particles in conductive composites have not arranged orderly, because that metal-coated conductive particles can hardly produce electric dipole moment by induction electric fields.