A silicone oil emulsion with 60% of solid content was prepared with methyl silicone oil used as the main material by means of the emulsifier-in-oil method.The influence of emulsification conditions on the droplet diam...A silicone oil emulsion with 60% of solid content was prepared with methyl silicone oil used as the main material by means of the emulsifier-in-oil method.The influence of emulsification conditions on the droplet diameter of silicone oil emulsion was discussed.The experimental results showed that the emulsification method,including the quantity of the emulsifier,the time and temperature of emulsification,the emulsifying water dosage,and the stirring speed,had significant impact on the droplet size.The optimal conditions were identified to achieve a smallest droplet diameter of the emulsion at an emulsifier dosage of 6%,an emulsification temperature of 70 ℃,an emulsification time of 30 min,and a stirring speed of 1100 r/min,with water added in two portions at a ratio of 1:1.The high-solid content silicone oil emulsion with a mean droplet diameter of 2.731 μm was prepared under these conditions that could ensure absence of stratification and floating oil under centrifuging at a speed of 3000 r/min for 30 min.展开更多
Flexible pressure sensors play an important role in the field of monitoring, owing to their inherent safety and the fact that they are embedded at the material level. Capacitive pressure sensors have been proven to be...Flexible pressure sensors play an important role in the field of monitoring, owing to their inherent safety and the fact that they are embedded at the material level. Capacitive pressure sensors have been proven to be quite versatile, with the ability to change the sensitivity and monitoring range by modifying the pore structure of the dielectric layer(elastic modulus). In this paper, capacitive pressure sensors are devised, comprising hierarchical porous polydimethylsiloxane. Due to the inherent hollow and hierarchical micropore structure, the capacitive pressure sensor allows operation at a wider pressure range(~1000 kPa) while maintaining sensitivity(6.33 MPa-1) in the range of 0–300 k Pa. Subsequently, the capacitance output model of the sensor is optimized, which provides an overall approximation of the experimental values for the sensor performance. Additionally, the signal response of the“break up the whole into parts”(by analysis of the whole sensor in parts) is simulated and outputted by the finite element analysis. The simplified analysis model provides a good understanding of the relationship between the local pressure and the signal response of the pressure sensor. For practical applications, seal monitoring and rubber wheel pressure array system are tested, and the proposed sensor shows sufficient potential for application in large deformation elastomer products.展开更多
文摘A silicone oil emulsion with 60% of solid content was prepared with methyl silicone oil used as the main material by means of the emulsifier-in-oil method.The influence of emulsification conditions on the droplet diameter of silicone oil emulsion was discussed.The experimental results showed that the emulsification method,including the quantity of the emulsifier,the time and temperature of emulsification,the emulsifying water dosage,and the stirring speed,had significant impact on the droplet size.The optimal conditions were identified to achieve a smallest droplet diameter of the emulsion at an emulsifier dosage of 6%,an emulsification temperature of 70 ℃,an emulsification time of 30 min,and a stirring speed of 1100 r/min,with water added in two portions at a ratio of 1:1.The high-solid content silicone oil emulsion with a mean droplet diameter of 2.731 μm was prepared under these conditions that could ensure absence of stratification and floating oil under centrifuging at a speed of 3000 r/min for 30 min.
基金supported by the National Natural Science Foundation of China(Grant No.52075119)。
文摘Flexible pressure sensors play an important role in the field of monitoring, owing to their inherent safety and the fact that they are embedded at the material level. Capacitive pressure sensors have been proven to be quite versatile, with the ability to change the sensitivity and monitoring range by modifying the pore structure of the dielectric layer(elastic modulus). In this paper, capacitive pressure sensors are devised, comprising hierarchical porous polydimethylsiloxane. Due to the inherent hollow and hierarchical micropore structure, the capacitive pressure sensor allows operation at a wider pressure range(~1000 kPa) while maintaining sensitivity(6.33 MPa-1) in the range of 0–300 k Pa. Subsequently, the capacitance output model of the sensor is optimized, which provides an overall approximation of the experimental values for the sensor performance. Additionally, the signal response of the“break up the whole into parts”(by analysis of the whole sensor in parts) is simulated and outputted by the finite element analysis. The simplified analysis model provides a good understanding of the relationship between the local pressure and the signal response of the pressure sensor. For practical applications, seal monitoring and rubber wheel pressure array system are tested, and the proposed sensor shows sufficient potential for application in large deformation elastomer products.
