Preparation Of Silver Nanowires Induced By Metal Ions With Different Valence States And Its Multifunctional Fibers/Fabrics

Smart textile is a typical intelligent material,which can sense and respond to various environmental changes or stimuli(such as force,electricity,light,magnetic,thermal and chemical environment).Currently,it has been widely used in detection and sensing,aerospace,medical care,sports and entertainment and other fields.Compared with the traditional sensor,the fabric-based sensor is stretchable,bendable,wearable,foldable and washable,which is more suitable for the use of non-planar structures.Moreover,the fabric-based sensor has good elasticity,and its working range as a strain sensor is wider than that of the traditional metal strain gauge.However,the current flexible strain sensor has problems,such as low sensitivity,small strain range and unstable performance after multiple stretching,and its functionality is single.In this study,a series of multifunctional fibers and fabrics with strain sensing properties were designed and prepared by inducing the growth of silver nanowires(Ag NWs)with different valent states of metal ions(Na⁺,Cu²⁺,Fe³⁺)and using waterborne polyurethane resin(WPU)to disperse Ag NWs and Multifunctional yarn and fabrics.This thesis focused on the generating mechanism of Ag NWs induced metal ions with different valence states and combination of Ag NWs with the elastic fabric.On the one hand,the formation of conductive network at low filling amount of Ag NWs improved the conductivity of the initial elastic fabric;on the other hand,waterborne resin as the bonding agent formed interface layer in the process of fabrication effectively improved the sensitivity and stability of strain sensor.At the same time the multifunction of anti-UV,anti-bacterial,electromagnetic interference shielding,electric heating was realized.The results showed that Ag NWs with diameter ratio of 1200 was synthesized by using monovalent NaCl as nucleating agent,polyvinyl pyrrolidone(PVP)with molecular weight of1.3 million as protective agent,reaction temperature of 130?and reaction time of 8 h.When the filling amount of Ag NWs was 10wt%,the strain range of PU/cotton@Ag NWs core spun yarn was 0-60%,the sensitivity was up to 12.6,and the strain sensing performance was stable after 100 times of repeated stretching.The strain range of the multifunctional fabric prepared was 0-60%,and the sensitivity was up to 107.5.It could be used for human tiny motion detection,and the strain sensing performance was stable after 100 times of repeated stretching.In addition,it had good washing resistance and excellent antibacterial,anti-UV,electromagnetic interference shielding and electro-thermal performance etc.