Fabrication of hierarchically porous structured PDMS composites and their application as a flexible capacitive pressure sensor. (15th April 2021)

• Record Type: Journal Article
• Authors: Hwang, Juwon; Kim, Yeongjun; Yang, Hyeondong; Oh, Je Hoon
• Is Part Of: Composites. Number 211(2021)
• Publication Date: 2021-04-15
• Subjects: Hierarchically porous polymer composite -- Capacitive pressure sensor -- Combined template method -- Wearable electronics; Composite materials -- Periodicals; Materials science -- Periodicals; Composite materials; Periodicals; Electronic journals; 620.118
• DOI: 10.1016/j.compositesb.2021.108607
• Languages: English
• ISSNs: 1359-8368

Abstract

Abstract: Pressure sensors for wearable electronics are mounted on irregular surfaces and exposed to various external stimuli. Therefore, the sensor should have a flexible structure and wide pressure measurement range along with high sensitivity. In this study, we fabricated hierarchically porous structured polydimethylsiloxane (PDMS) composites with a simple and cost-effective method using sugar particles and a water-in-oil emulsion. Hierarchically porous PDMS composites were employed as the dielectric layers of flexible capacitive pressure sensors. The capacitive pressure sensor presents a sensitivity 22.5 times higher (0.18 kPa −1 ) than the sensors using bulk PDMS with a wide measurement range (0–400 kPa). The finite element analysis was implemented to analyze the non-linearity of sensors by observing the compressive behavior of the PDMS composites. For the practical applications, finger attached-sensor, respiration monitoring system, and sensor array were tested, and the proposed sensors showed sufficient potential for application in wearable electronics.