Personal Thermal Management Fabric Based On Polyamide 6

The energy and thermal management clothing are becoming an increasingly important and attractive aspect due to our increasing awareness to energy consumption and our persisting pursuit of comfort and health.At present,with the rapid development of material science and textile technology,different personal thermal management fabrics have been reported,such as air cooling,liquid cooling,phase change cooling,wicking-evaporative cooling,semiconductor cooling and optical control cooling fabrics.However,the cutting-edge personal thermal management fabrics still have many problems and challenges:（1）Active personal thermal management fabrics consume energy,and some of them are heavy and not suitable for daily use.（2）The external flexible devices used in some thermal management fabrics have poor integration with clothing.（3）The mechanism of personal thermal management is limited and it is difficult to achieve efficient adjustment for both temperature and humidity.（4）Wearable performance such as washing resistance,abrasion resistance and air permeability are poor.In view of the above problems and challenges,this work focus on the fabric materials,structure and personal thermal management regulation mechanism.Through in-depth researches on the preparation of nanofiber fabrics,filament fabrics,and the personal thermal management principle,we improved the cooling efficiency and wearing comfortability of thermal management fabrics.The specific research content is as follows:（1）The polyamide 6（PA6）/silicon oxide（SiO₂）nanofiber fabric with daytime radiative cooling effect is prepared by high-voltage electrospinning.The fabric has a controllable micro-nano network structure,which can effectively reflect sunlight and reduce the heat from sunlight.Meanwhile,the infrared transmission material PA6 can effectively transmit the infrared radiation of the human body,and the randomly distributed SiO₂ microspheres can effectively radiate the infrared radiation of 9μm emitted by the human body,which jointly achieve the purpose of personal cooling.（2）A moisture wicking passive cooling fabric,PA6/SiO₂/cellulose acetate（CA）/aluminum oxide（Al₂O₃）/HPX（moisture control agent）nanofiber fabric,was prepared by electrospinning and dip coating.The stretching vibration of C-H,C-O,C-O-C and C-OH in CA,the strong phonon polaron resonance of SiO₂（～9μm）and Al₂O₃（～12μm）,the excellent infrared transmission performance of PA6 and the controllable micro-nano network structure all endow the fabric with excellent optical control capabilities.Furthermore,the application of the moisture control agent and the difference pore size of the double-layer give the fabric significant wettability gradient which supports the transfer of sweat from the inner layer（CA/Al₂O₃/HPX layer）to the outer layer（PA6/SiO₂/HPX layer）to achieve ultra-fast evaporation.The optical control cooling and wicking evaporative cooling can improve the cooling efficiency and effectively maintain the personal thermal comfort.Experimental results verify that the PA6/SiO₂/CA/Al₂O₃/HPX nanofiber fabric enables simulated skin to prevent overheating by 16.6℃ compared to traditional textiles.（3）Using infrared-radiation-enhanced material SiO₂ and infrared transparent material PA6 as raw materials,we adopted industrialized melt spinning methods to prepare fibers with passive radiative cooling effect.Then we weaved fibers into a plain weave fabric through a manual loom.The night cooling test indicates that the addition of inorganic particles increases the radiative cooling performance of the fabric.When the size of SiO₂particle is 4μm and the mass ratio of SiO₂ is 5%,the SiO₂/PA6 radiative cooling fabric can enable simulated skin to avoid overheating by 4℃ compared to pure PA6 fabric.