Preparation And Properties Of Functional Textile Materials Deposited With Ag/FC Films By Magnetron Sputtering

With the development of science and technology,electromagnetic radiation is now becoming the fourth largest pollution after water pollution,air pollution and noise pollution.Magnetron sputtering is a new technology for the surface functionalization of the textile materials,with characteristicsincludinglowtemperaturedeposition,lowcost,eco-friendliness and easy controllability.Has important significance to prepare the textile materials with electromagnetic shielding function though magnetron sputtering technology in theory and application.In this paper,Ag,FC and Ag/FC composite films were successfully deposited on the surface of textile materials by using magnetron sputtering techniques with pure silver?Ag?and polytetrafluoroethylene?PTFE?targets.The surface morphology,physical and chemical structure,hydrophobic properties,electrical conductivity and electromagnetic shielding properties of the Ag,FC and Ag/FC coated textile materials were then studied.The growth pattern of the films,the interface bonding mechanism and the timeliness were also investigated.The main contents and conclusions were as follows:The growth pattern of Ag on the surface of PET fibers is the Volmer-Weber growth model,the process as follows:firstly Ag particles deposited and generated nuclei on defect part of PET fiber surface,and then nuclei grew up in three-dimensional directions into isolated island,interconnecting into a continuous film,which conforms to the island growth pattern.FC film deposited on the surface PET fiber initially showed rod-like and granular growth,the etching effect would damage the surface of substrate materials and the continuous film was formed as the sputtering time was prolonged.In the deposition of the FC film layer,the Ag/FC layer is deposited in the defect location of the growth Ag film,and then the continuous film is formed.The growth pattern of the Ag/FC composite films coated on PET fiber by co-sputtering is Volmer-Weber model.The amount of Ag and F elements on the deposited film surface is related to the parameters of magnetron sputtering and it is evenly distributed on the surface of the PET nonwoven fabrics.In the single layer Ag film,Ag/FC multilayer film and Ag/FC composite film,the Ag is in the state of elemental and no chemical reaction occurred.PTFE material via magnetron sputtering deposited on the surface of PET substrate and fractured into FC macromolecular chain structure containing-C-C-,-C-CF-,-CF-,-CF₂-and-CF₃ groups.It was observed that vibration peak of-CF₂-groups appeared at the wave numbers of 1200-1250cm-1,and the F/C atomic percentage is lower than PTFE target itself.The Ag?111?,?200?,?220?,?311?and?222?crystal planes characteristic peaks were found in the Ag film and the Ag/FC multilayer film,which was along the?111?plane orientation.The crystallinity increases as the sputtering power increases and Ag exhibits an amorphous state in Ag/FC composite film by co-sputtering.The static contact angle?CA?of FC film deposited on the surface of PET nonwoven increases with the increasing of sputtering time and sputtering power.Once the contact angle reaches 140°,the increase of sputtering time and sputtering power of PTFE will no longer had significant effect on CA.The gas pressure has little effect on the contact angle in the range of 0.55-2.0 Pa and the contact angle decreases with the gas pressure in the range of2.0-10.0 Pa.The contact angle of the deposited Ag/FC multilayer film is larger than that of the FC film,which reaches 145.21°.The static contact angle of PET nonwoven fabrics with Ag/FC composite film by co-sputtering decreases with the increasing of Ag content.The surface resistance of Ag film coated on PET nonwoven fabric decreased as the sputtering power and sputtering time increased.But once the continuous film formed,the increase of sputtering power and sputtering time will no longer had significant impact on the resistance value.The surface resistance of Ag/FC multilayer film deposited on PET nonwoven fabric increased as the thickness of FC layer increased.When the sputtering parameters of Ag/FC composite film were 30 W/50 W,15min and 0.55 Pa,the surface resistivity decreases sharply,and the conductive network is formed.Electromagnetic shielding effectiveness?SE?of PET nonwoven fabric coated with Ag film is greatly influenced by sputtering power and sputtering time,and slightly affected by the working gas pressure?0.55-2.0 Pa?,ranging from30 MHz to 1.5 GHz.With the increasing of the thickness of the FC layer,the average Electromagnetic SE of Ag/FC composite film first increases and then decreases;which was caused by the occurrence of resputtering phenomena during the FC sputtering.The Electromagnetic SE of the Ag/FC composite film deposited on PET nonwoven fabric is consistent with the changing trend of the surface resistance,and is stronger than those of Ag film deposited on PET nonwoven fabric.The thickness and pore structure of the nonwoven fabric itself have a great influence on the Electromagnetic SE.Deposition of Ag film on the surface of PET nonwoven fabric,along with the increasing of sputtering power and sputtering time,the surface resistance decreases,Once a continuous film formed,the increase of sputtering power and sputtering time will no longer have significant impact on its surface resistance.The corrosion resistance of the samples was analyzed through hydrogen sulfide corrosion experiment.The results showed that the PET nonwoven fabric deposited with Ag/FC multilayer film and Ag/FC composite film can slow down the Ag reaction with sulfur-containing small molecules.The adhesion between Ag/FC composite film and PET nonwoven fabric is the largest in all samples,which proves that the composite structure is beneficial to interfacial bonding.