Research On Preparation And Properties Of Carbon Fiber/Nickel/PP Electromagnetic Shielding Composites

With the development of information technology and widespread use of electromagneticwave, our environment is full of electromagnetic radiation. Electromagnetic radiation isrecognized as the fourth largest pollution after the air,water and noise pollutions.Electromagnetic radiation will not only cause electromagnetic interference, destroy thenormal operation of the electronic and electrical equipments, but also threaten human’shealth.Electromagnetic shielding materials with good shielding effect become a hotresearch，many countries have done a lot of researches in the development of new shieldingmaterials. Filler type composite electromagnetic shielding materials gain more attention forthe superior performance. Our country get behind other countries in this field,so studying onnew electromagnetic shielding composite materials has important practical significance.Composite blending with carbon fiber have conductivity and good mechanicalproperties,but low shielding efficiency.In order to gain better electromagnetic shieldingperformance in the wide frequency range, electromagnetic shielding materials should be thecombination of high magnetic conductance materials and high conductivity materials. In thispaper,carbon fiber and nickel fill with PP to make electromagnetic shielding compositematerials.The cohesiveness between carbon fiber and PP is weak, and dispersiveness of fillersis not good,so make surface treatment on carbon fiber and nickel with titanate couplingagent respectively. Effect of addition of carbon fiber and nickel on conductivity、shieldingefficiency in1GHz to18GHz range and mechanical properties of shielding composition isstudied in this paper.Compare CF/PP and CF/Ni/PP composites comprehensive properties toexplore a new preparation method of electromagnetic shielding materials.Results showed that shielding effectiveness of composite increased fluctuantly as the riseof frequency in1GHz to18GHz range. Shielding effectiveness of CF/PP composite increasedand mechanical properties first increased then decreased with the increase of carbon fibercontent.Shielding effectiveness increased after adding nickel with the same carbon fibercontent， but the optimum nickel addition was different with different carbon fibercontent.When carbon fiber content was2%or5%,shielding effectiveness was best with nickel addition was12%and mechanical properties decreased with increasing nickel content.Whencarbon fiber content was10%or15%,shielding effectiveness reached optimum with nickeladdition was15%and mechanical properties fluctuated with increasing nickel content.The composite with15%carbon fiber content and15%nickel addition had the optimumshielding effectiveness,which average value was40.07dB and the maximum was49.49dB.The composite had best mechanical properties when carbon fiber and nickel additionwas15%and8%respectively.The breaking elongation of CF/Ni/PP composite is higher thanCF/PP composite with same fillers content.