Mechanical and thermal characterization of condom industry waste reinforced natural rubber composites - Circular economy approach

Abstract

Condom industry waste mainly consists of light magnesium carbonate (LMC), which is extensively used as a finishing powder during the final stages of condom production. This LMC waste (LW) is usually disposed of as a landfill, causing an increase in the hardness of water. LW generated in HLL Lifecare Limited, India, was procured, characterized by analytical techniques, and reutilized in natural rubber (NR) as a reinforcing filler. The prepared composites were subjected to rheological, mechanical, thermal and sorption characterizations. In comparison to NR neat, the composite with 3 phr (parts per hundred of rubber) LW showed a rise in tensile strength, tear strength, and modulus at 300% elongation by 22%, 20%, and 28%, respectively. A remarkable decrease in abrasion loss is also evidenced. The activation energy (Ea) for degradation, calculated by the Coats-Redfern (CR) method, showed 10 kJmol-1 increase for composite with 3 phr LW, proving its better thermal stability. It also exhibited higher solvent uptake resistance, as established by sorption experiments. The superior properties of this composite have been attributed to the uniform LW distribution and ameliorated NR-LW interaction. Hence, the prepared composites find considerable potential in manufacturing industrial NR components accomplishing a circular economy.