Development of flexible solvent sensors from natural rubber and EPDM rubber nanocomposites

• Grant number: 25/01273-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2025
• End date: January 31, 2026
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Rafael Barbosa
• Grantee: Vinícius Toassa Corrêa
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Belonging to the area of smart polymers, conductive elastomeric composites (CECs) have been investigated for application in flexible electronics. One of the promising aspects is the use of these composites as piezoresistive solvent sensors. It is based on the swelling behavior of crosslinked polymers in the presence of solvents, which separates the conductive charges increasing the resistivity of the compound. In this project, CECs will be prepared with the incorporation of carbon nanotubes in natural rubber latex assisted by ultrasound and surfactants and subsequent mixing of this rubber with EPDM rubber in different proportions. The objective is to understand what morphology is formed in these blends after vulcanization, the electrical and mechanical properties found and the effect of differential swelling of the phases in specific solvents for the sensing capacity. The effect of protection against temperature-catalyzed oxidation of EPDM in natural rubber will be evaluated by differential scanning calorimetry, determining the oxidation onset temperature of the prepared composites. Therefore, it is expected at the end of the project to obtain mechanically reliable, electrically conductive, oxidation resistant devices that act as sensors for organic solvents.