碳化工艺对蚕丝包覆纱性能的影响OA

Flexible strain sensors have attracted the attention of a large number of scholars and have shown great potential applications in many fields such as medical,electronic skin and intelligent robots.However,the detection range of traditional metal or inorganic semiconductor commercial sensors is very limited(about 5%),and signal instability is prone to occur due to the characteristics of rigid materials. As a common textile fiber material,silk possesses good flexibility,biocompatibility,and mechanical properties,and is easily degradable,making it environmentally friendly.The fibroin in silk mainly consists of a β-sheet structure.Under inert gas atmosphere conditions,it is converted into a six-ring graphite carbon structure with excellent conductivity after high temperature carbonization.Therefore,the carbonized silk material can be used as a matrix material for flexible sensors.The properties of carbonized silk materials produced by different carbonization processes are different.This is mainly because the β-sheet structure in silk fibroin is transformed into a six-ring graphite carbon structure under different carbonization conditions,which in turn affects the mechanical properties and electrical conductivity of the material.In addition,the yarn structure has an important influence on the construction of the conductive network.The coated yarn structure can make the sensor obtain a larger strain range and improve the sensitivity. In this paper,carbonized silk-coated yarns were prepared by high temperature carbonization method and combined with the special structure of coated yarns.The effects of carbonization process parameters such as heating rate,carbonization temperature and carbonization time on the resistance and mechanical properties of coated yarn were systematically investigated.The flexible strain sensor was prepared by elastic packaging technology,and the effect of carbonization process on the sensing performance was studied.The results showed that the fracture strain of the yarn increased with the decrease of the heating rate,carbonization temperature and carbonization time in the first stage.With the increase of the second stage heating rate,carbonization temperature and carbonization time,the yarn resistance decreased.When the heating rate of the first stage was 3℃/min,the heating rate of the second stage was 4℃/min,the carbonization temperature was 900℃and the carbonization time was 60 min,the fracture strain of the carbonized silk yarn(CSYS)with the largest fracture strain was 52.06%.When the heating rate of the first stage was 4℃/min,the heating rate of the second stage was 5℃/min,the carbonization temperature was 1000℃and the carbonization time was 180 min,the resistance of the carbonized silk yarn(CSYR)with the smallest resistance was 47.1 Ω/cm.The strain range of the CSYS-based sensor was 53%,the sensitivity was 4.98,and the linearity was 0.957.The strain range of the CSYR-based sensor was 42%,the sensitivity was 12.52,and the linearity was 0.972.The CSYS sensor has higher durability and faster response speed,and can be used to detect the motion information of different parts of the human body,showing good signal recognition ability.The research results can provide reference for the development of silk-based flexible strain sensing.