Investigations on thermal and mechanical characteristics of PDMS embedded FBG sensors for wearable sensing applications

Abstract Fiber Bragg Grating (FBG) sensors embedded in polydimethylsiloxane (PDMS) are suitable for real-time monitoring of parameters like strain, temperature, force etc. This work investigates the thermal and mechanical properties of PDMS samples at mixing ratios of 6:1, 10:1, and 15:1 with embedded FBGs. The 10:1 sample showed the highest temperature sensitivity of 22.51±0.54 pm/◦C. Young’s modulus values from mechanical characterization ranged from 2.20-8.16 MPa, 2.56-7.68 MPa, and 0.44-5.02 MPa for mixing ratios 6:1, 10:1, and 15:1, respectively. The highest force and strain sensitivities were 1.356 nm/N and 0.153 pm/µϵ for the 10:1 ratio, making it preferable for wearable sensors.