Stretchable Dielectric Substrate Manufacturing for Printed Electronics

S. Deshmukh, E. Keaney, C. Barry, J. Mead
University of Massachusetts Lowell,
United States

Keywords: stretchable electronics, substrate manufacturing, butyl rubber, barium strontium titanate, composites, compounding, curing

Summary:

Stretchable electronics are being used in various applications such as wearable electronics, robotic skin, wearable health monitoring devices, and smart textiles due to their excellent mechanical conformability through stretching, flexing, twisting, and folding. This work focuses on batch mixing and compression molding a thin stretchable dielectric substrate with a ferroelectric filler, barium strontium titanate (BST), in a base elastomer, butyl rubber (IIR). BST is incorporated to enhance the dielectric properties of the substrate compared to current commercially available elastomers substrates. To achieve the material improvement in terms of dielectric properties, a high loading of BST is required. Although the filler improved the electrical properties, material and mechanical properties such as filler-elastomer interaction, curing, flexibility and stretchability of the substrate was compromised with increased filler loading. The effect of BST loading on the material, mechanical and electrical properties is evaluated. The work also addresses the difficulties in substrate manufacturing in detail. At last stretchable conductive ink is selected for printing a square design to measure conductivity for both single and multiple stretch cycles.