Research On Surface Modifaction Of Nomex With Excimer UV Light Source

Excimer UV light source is a new high-power,incoherence and only decade history UV source,and it is expected to be an effective method for functional fibers and continuous waterlessness equipment.In recent years,high-performance fibers have developed rapidly,while Nomex fiber as these fibers has been broadly applied in bunker clothing and insulation papers,but it is difficultly made to the composite materials with resins because of its smooth surface.Lately, part of countries developed magnetic functional fibers in succession,and this kind of magnetic functional fiber with certain uniform magnetic field intensity is woven to fabric,and then made to clothes.These clothes not only have better magnet therapy,but also comfortable wearing.The magnetic product made from it can be used in magnetic recording,magnetic memory, electromagnetic change-over,magnetic shielding and protection,medical treatment and biotechnology,isolation and purification,etc.While it will be broad prospect and important meanings that Nomex fabric as a magnetic material is applied in functional protective（particularly absorbing materials）.In this paper,we firstly choose excimer lamp at wavelength of 172nm to treat Nomex fabric with single-side directly,and the modification mechanism is explored via changing irradiated atmosphere（air,nitrogen and argon）.The results showed that wettabilitys in both nitrogen and argon were superior to that in air,but all had the certain timeliness with slight yellow.SEM and XPS testings reveal that the surface of the Nomex fiber takes place the photo-oxidation after irradiated by the 172nm excimer UV lamp,and the surface is etched and hydrophilic functional groups such as carboxylic acid are produced.These two factors lead to the improvement of the wetting property.As the result of the etchings and wettability,the adhesive strength of the N/PE composites irradiated by 172nm excimer UV lamp has been increased 93.57%,thus this improved the adhesive property of the composites greatly.Meanwhile the dyeing property of the Nomex fabric was improved,too.The improvement of these properties shows the application performance of the Nomex has been increased after irradiated with excimer UV lamp.Following,the Nomex fabric irradiated with excimer UV lamp was infused in Fe₃O₄ magnetofluid to prepare the magnetic fabric.The result showed that the prepared Nomex fabric had better superparamagetism,and the hysteresis loop of the fabric displayed zero residual magnetism and zero coercive force.The saturation magnetization of the fabric decreased with the washing times,but the decline of the irradiated sample was lower than that of the non-irradiated sample.This revealed that the washing fastness and rubbing fastness after treatment had improved.Finally,the change of physical properties was researched when the magnetic Nomex fabric was irradiated in different atmosphere and time.Before washing,the magnetic weight ratio of the Nomex fabric change little with the irradiated time.After washing 20 times,the magnetic weight ratio in nitrogen atmosphere is the biggest.But because Fe₃O₄ particles tend to link with-COOH and the magnetic shielding was resulted from the etching,the saturation magnetization in air was higher than that in anoxic atmosphere.Also the strength loss of the fabric after this treatment is lower,and the body structure of the Nomex fiber won’t produce any influence.The LOI value testing illustrated magnetic finishing had certain combustion which is very little,and this combustion won’t have an affect on the inflaming retarding of the Nomex fabric.