Research Based On AGNWS/PDMS Flexible Tensile Strain Sensor

Flexible tensile strain sensors as wearable sensors in the field of an important part,by virtue of its good mechanical properties and repeatability,sensitivity,linearity and hysteresis and other characteristics are widely used in health monitoring system.Silver nanowires are widely used in the preparation of flexible sensors because of their good electrical properties,optical properties and unique structural features.In this study,polyvalent alcohol method was used to prepare silver nanowires with uniform morphology in 30 minutes by adding cupric chloride solution as nucleation control agent.The nanowires were characterized by scanning electron microscopy,UV spectrophotometer and XRD.Using self-made silver nanowires as the conductive material and polydimethylsiloxane(PDMS)as the base material,no modification of other reagents is needed,and only semi-dry PDMS adhesive nanowires are used to make the flexible conductive film and then assembled into a simple flexible tensile strain sensor.By changing the concentration of silver nanowires(0.5 mg/cm,1 mg/cm,1.5 mg/cm2 and 2 mg/cm),to explore the impact of changes in the concentration of the sensor performance.The mechanical properties as well as repeatability,sensitivity,linearity and hysteresis were tested by universal testing machine and universal digital meter.And flexible tensile strain sensor installed in the human knee,finger bending test.Through the characterization of silver nanowires,it was proved that the silver nanowires with high aspect ratio were prepared rapidly by the polyol method with the average diameter of 53 ±9nm,the length of 31 ± 7?m and the aspect ratio of 584.9.By EDS characterization,to prove the pure silver nanowires prepared successfully.The addition of silver nanowires improves the mechanical properties of flexible conductive films.When the concentration of silver nanowires is 1 mg/cm2,the maximum breaking load is 14.97N,and the repeatability is the best at this concentration.The maximum variation of resistance is 25?.When the concentration of silver nanowires is 0.5mg/cm2,the sensitivity of silver nanowires is lowest,only 0.53.However,with the increase of silver nanowires concentration,the sensitivity increased significantly.When the concentration of silver nanowires is 1.5mgicm,the sensitivity is the highest,reaching 4.18;when the concentration of silver nanowires is 1 mg/cm2,the sensitivity is 3.65,which is relatively good.The linearity of the sensor is the best when the silver nanowire concentration is 2mg/cm2,reaching 95.79%.The maximum hysteresis error firstly increases and then decreases with the increase of silver nanowire concentration.When the silver nanowire concentration is 2 mg/cm2,the maximum hysteresis error of the flexible sensor is the smallest,which is 29.5%.Installed in the human body,the resistance of the flexible strain sensor changes with the movement of the human body,can well reflect the movement of the human body.