Preparation And Performance Of Rubber Based Resistance Flexible Strain Sensor

With the progress of society,more and more health problems have attracted people's attention.Due to its ability to timely,effectively,and conveniently detect physiological signals of the human body,flexible strain sensors have received extensive attention.In this dissertation,flexible strain sensors made of three systems,carbonized natural fiber fabric/Ecoflex rubber,carbon black/carbon nanotube/silicone rubber,carbon black/carbon nanotube/natural rubber,were studied.The preparation process was investigated and the morphology and structure were characterized by scanning electron microscopy and Raman spectroscopy.The mechanical and electrical properties were measured using an electronic universal testing machine and a keithley 2400.The resulting flexible strain sensor responded sensitively to human joint motion,respiration,tension,vocal cord sound(numbers,letters,songs),and has better cycle stability and fatigue resistance.Carbonized natural fibers / Ecoflex system of the kind of natural fibers(flax,bamboo,etc.),a braided structure,the carbonization temperature,carbonization atmosphere,and other conditions were discussed,determined excellent process parameters.Finally,a carbonized flax fabric/Ecoflex rubber-based flexible strain sensor was obtained and its strain response was examined.Carbon black/carbon nanotubes/silicone rubber is mainly studied for the best carbon black(CB)and carbon nanotube(CNT)filling content(2%,4%,6%,8%,10%,12%,15%),and the influences on the electrical properties and sensitivity of the flexible strain sensor,and the characterization of mechanical electrical properties after the mixture of the two are explored.The flexible strain sensor prepared with 4% content of carbon nanotubes and 6% content of carbon black has the best sensitivity,and the mixing of the two in the ratio of 2:3 can improved their electrical and mechanical properties.Carbon black/carbon nanotubes/natural rubber improved the cycle performance and fatigue resistance of the flexible strain sensor under the premise of maintaining excellent electrical performance.At the same time,different content of silver-coated glass microspheres(10%,20%,30%,45%,70%,75%,80%,85%)of composite natural rubber was used to prepare flexible strain sensors,and their electrical properties were discussed.The carbon black/carbon nanotube/natural rubber flexible strain sensor finally prepared in this paper can responded well to the change,and the cycle,sensitivity and fatigue resistance were good,and the resistance showed regular change with the strain.The sensor can withstand strain of 130%,accumulated experience for wearable sensors,smart clothes,health monitoring,and motion detection in the future.