Study On The Preparation And Properties Of Conductive Glass Fabrics And Their Epoxy Resin Composites

With the development of science and technology,the use of electronic products and equipment have made great progress,however these electronic products and equipment will produce different levels of electromagnetic radiation,which would cause the interference between electronic products,and harm to people's health.Thus,people have taken more attention to protect the electromagnetic radiation.At present,protection materials used in electromagnetic radiation were usually prepared by metal coating method.Now,the methods to deposit metallic coatings on the surface of substrates are mainly focused on conductive coating,vacuum coating,sputtering coating,spraying and electroless plating.Among these methods,electroless plating was a simple and inexpensive technology and the coatings obtained with uniform coatings and excellent conductive.What's more this method can be used in conductive,nonconductive and complicated shape matrix materials.Nowadays many fibers can be metallized by electorless plating method.The metalized fabrics not only possess flexibility and other some inherent excellent properties of the fabrics,but also have conductivity of metal,so metalized fabrics have became a kind of new functional materials,and these materials have potential applications in the field of conductive fillers,electromagnetic shielding,medical,memory materials and so on.Epoxy resin(EP)was currently used in the preparation of excellent composite matrix,which has good mechanical properties,insulation performance,processing performance and so on.It can be combined with glass fiber,carbon fiber,hybrid fiber and its fabrics to prepare functional composites materials,thereby broadening its application in electronics,defense and other industriesIn this paper,we have prepared cobalt or nickel coated glass fabric composites(Co/GFF and Ni/GFF)by electroless plating method using glass fabric as matrix materials,and then nickel-coated glass fabric/epoxy resin(Ni/GFF/EP)and glass fabric/epoxy resin(GFF/EP)composites were prepared using Ni/GFF and glass fabric as fillers and EP as matrix materials,respectively.In this work,we have firstly studied the roughening process of the glass fabric in the process of pretreatment,in order to improve the hydrophilicity of the fabric surface and the bonding properties between coatings and fiber matrix.Secondly,the influence of electroless plating parameters on the conductivity and microstructure in the electroless cobalt or nickel plating process were researched in details.Finally,we prepared Ni/GFF/EP and GFF/EP,and studied the mechanical properties and shielding property.The results of this work were listed as follows:1)Roughening the glass fabric surface using sodium hydroxide solution,and studying the influence of the roughening concentration,roughening temperature and roughening time on the conductivity,bonding properties and microstructure of the sample,respectively.Finally,obtained the optimum roughening conditions: the roughening concentration,roughening temperature and roughening time was 40 g/L,60 ?,30 min,respectively.In these conditions,not only the specific surface area and surface activity of the glass fabric were increased,but also the adhesion between the fiber matrix and metal coatings was improved.2)Co/GFF and Ni/GFF composites with complete,dense,and uniform coatings were successfully prepared by electroless plating method,and the influence of electroless plating parameters on the conductivity and microstructure were studied respectively.The results showed: the volume resistivity of the Co/GFF and Ni/GFF was 1.61×10-2 ?·cm and 6.25×10-3 ?·cm,and the shielding properties was 37-43 and 58-61 dB in the frequency of 2-18 GHz,respectively.The research indicated that with increasing of the reaction temperature the saturation magnetization of the Co/GFF was increased and the coercivity of the Co/GFF was decreased.In addition,the enlargement experimental of the nickel plated process showed that the sample obtained with excellent conductivity of volume resistivity was 5.0×10-3 ?·cm,moreover the complete,uniform and dense coatings were covered on the surface of the fabric.3)The Ni/GFF/EP and GFF/EP composites were prepared using Ni/GFF or glass fabric as fillers and EP as matrix materials,respectively.The shielding performance and mechanical properties were studied.The results showed that the bending strength and impact strength of the Ni/GFF/EP was 225.59 MPa and 11.54 k J·m-2,which was decreased by 53.6% and 14.83% relative to the GFF/EP,respectively.However the shielding performance of Ni/GFF/EP could research 64-76 dB in the frequency of 2-18 GHz,which was increased relative to the Ni/GFF,this was due to the conductivity and multiple reflection performance between Ni/GFF of the Ni/GFF/EP was increased,so the shielding performance of the Ni/GFF/EP was greatly improved.