Influence of curing temperature on mechanical and viscoelastic properties of siliglass platinum silicone for Fiber Bragg Grating sensors encapsulation in flexible and wearable applications

Applications in flexible wearable devices and wearable electronics for health monitoring purposes often rely on soft materials whose mechanical and viscoelastic properties can be precisely tuned and controlled. Siliglass, a platinum-cured silicone, is a promising candidate due to its flexible characteristics, biocompatibility, and tunable performance. This study investigates the effect of curing temperature (25 degrees C, 50 degrees C, 75 degrees C) on the mechan ical behavior and stress-relaxation of Siliglass. Uniaxial tensile tests revealed a strong dependence on curing conditions: elongation at break decreased from 97% to 34% as temperature increased, while Young's modulus rose by over 60%. Poisson's ratio remained close to 0.5, confirming the near incompressibility of the material. Stress-relaxation tests showed that both initial strain and strain rate significantly influence relaxation dynamics, with faster stress decay observed at higher curing temperatures. Finite element simulations help in evaluating the experimental results, confirming the consistency of the outcomes. The findings highlight the capacity for adjustment of Siliglass properties via curing temperature, suggesting the optimal one for flexible and wearable device applications.