# Stretch Sensor: Development of Biodegradable Film

## TL;DR

Researchers developed a biodegradable stretch sensor using κ-carrageenan and iron oxide microparticles, improving mechanical properties and sensitivity.

## Contribution

A novel biodegradable stretch sensor composition using κ-carrageenan and Fe2O3 microparticles is developed and tested.

## Key findings

- Incorporating Fe2O3 microparticles improved Young’s modulus but reduced elongation percentage.
- The GF of the films ranged from 0.67 to 10.47 depending on composition.
- Sensors achieved up to 10% elongation and demonstrated good sensitivity and stability.

## Abstract

This article presents research on biodegradable stretch sensors produced using biological material. This sensor uses a piezoresistive effect to indicate stretch, which can be used for force measurement. In this work, an attempt was made to develop the composition of a sensitive material and to design a sensor. The biodegradable base was made from a κ-carrageenan compound mixed with Fe2O3 microparticles and glycerol. The influence of the weight fraction and iron oxide microparticles on the tensile strength and Young’s modulus was experimentally investigated. Tensile test specimens consisted of 10–25% iron oxide microparticles of various sizes. The results showed that increasing the mass fraction of the reinforcement improved the Young’s modulus compared to the pure sample and decreased the elongation percentage. The GF of the developed films varies from 0.67 to 10.47 depending on composition. In this paper, it was shown that the incorporation of appropriate amounts of Fe2O3 microparticles into κ-carrageenan can achieve dramatic improvements in mechanical properties, resulting in elongation of up to 10%. The developed sensors were experimentally tested, and their sensitivity, stability, and range were determined. Finally, conclusions were drawn on the results obtained.