Preparation And Properties Of Ni/PANI/PTT Electromagnetic Shielding Fabric

The electromagnetic wave can not only cause the electromagnetic interference and damagefor the electronic instruments and equipment, but also give rise to the electromagnetic pollutionfor the environment, and the electromagnetic radiation does harm to people’s health. Therefore, avariety of the functional electromagnetic shielding fabrics produce in order to reduce or eliminatethe electromagnetic radiation interference, and the damage for the human. At present, a lot of theprotective mechanism of the electromagnetic shielding fabrics are mainly reflection, scatter, and asmall amount of the transmission. However, they can cause again the secondary pollution for theenvironment. So the emphasis should develop the electromagnetic shielding fabric that is givenpriority to the absorption loss, and increase the absorption value, which can have thoroughly theshielding effect. This topic contrapose the above problems, it puts forward using intrinsicconductive polyaniline with the microwave-absorbing characteristics and the metallic nickelhaving the magnetic conductivity, and the main absorption loss to get the soft electromagneticshielding fabric.This paper uses the polytrimethylene-tereph-thalate(PTT) fabric as substrate material and theaniline(An) monomer as raw material to produce the polyaniline(PANI)/PTT compositeconductive fabric by in-situ chemical polymerization. Then, it studies the concentration of anilinemonomer(An), ammonium persulfate(APS), hydrochloric acid(HCl), and polymerization reactiontime to influence on the properties of the PANI/PTT composite conductive fabric. Meanwhileutilizing the SEM, FTIR, XRD analyze and observe the PANI/PTT composite conductive fabric,and it analyses the change of the compound fabric in mechanical properties. The results show thatelectrical conductivity of the PANI/PTT composite fabric are very well at the concentration of An0.4mol/L, APS0.4mol/L, HCl1.25mol/L, and polymerization reaction time120min. And it hasthe best electromagnetic shielding effectiveness when the concentration of An0.4mol/L, APS0.5mol/L, HCl1.25mol/L, polymerization reaction time120min, and the maximum shieldingeffectiveness of composite fabric is about9~10dB in the range of300kHz~3GHz. SEM canobserve that the PANI are attached to the PTT fabric to form a conductive network access, andFTIR indicates that the PANI don’t introduce new impurities in the polymerization system, so thepurity of compound fabric is very high and the molecular chemical structure of PTT fabric have nodamage. Besides, XRD illustrates that the PANI diffuses into the compound fabric to breakgradually the ordered arrangement of atoms and the amorphous area is bigger, which results in thecrystallinity of the fabric decreased. The strong tensile test results showed that polyaniline have aninfluence on the mechanical property of the fabric, and after polymerization the fabric breakingstrength is increased, but the elongation at break is decreased.A layer of Nickel(Ni) on the PANI/PTT composite conductive fabric is obtained by themethod of chemical plating, which can get a better Ni/PANI/PTT electromagnetic shielding fabric of the conductivity and electromagnetic shielding effectiveness. It discusses the main factorsincluding the concentration of nickel sulfate, sodium hypophosphite, sodium citrate, and sodiumacetate to influence on the properties of the electromagnetic shielding fabric. Also using the SEMto study the coating surface morphology of Ni/PANI/PTT electromagnetic shielding fabric, and itanalyses the change of the compound fabric in mechanical properties. The results show that theelectrical conductivity and shielding effectiveness of the Ni/PANI/PTT electromagnetic shieldingfabric are very well at the concentration of NiSO425mol/L, NaH2PO220mol/L, Na3C6H5O715mol/L, CH3COONa20mol/L, and the maximum shielding effectiveness of composite fabric isabout42~43dB in the range of300kHz~3GHz. The coating surface morphology of theelectromagnetic shielding fabric is analysed via the SEM, and the results show that the continuous,compact and uniform layer of the metal Nickel deposits on the PANI/PTT composite fabricsurface through electroless plating in order to form a conductive network access andelectromagnetic shielding layer. Meanwhile, The strong tensile test results showed that thechemical nickel-plating have a great influence on the mechanical property of the fabric, and afternickel-plating the fabric breaking strength is obvious increased, and the elongation at break issilght improved.