Synthesis and Characterization of Limonene-Based Sulfur Polymer

Abstract

In this research, a sulfur-based polymer has been synthesized with limonene extracted from orange peels. The synthesis process has been carried out by dropping limonene at 0 wt.%, 0.5 wt.%, 1 wt.%, 2 wt.%, and 4 wt.% ratios into the molten sulfur. The change in the chemical bond structure of the synthesized sulfur-based polymer is determined by Fourier Transform Infrared Spectrophotometer (FTIR). Moreover, the density, Shore D hardness, and thermal conductivity coefficient of the sulfur-based polymer are also characterized. According to the evaluations, it has been seen that limonene extracted from 1% orange peel gave the best results. It has been observed that the polymerization efficiency is low when used below 1 wt.% by mass. At higher rates, Shore D hardness of the sulfur-based polymer decreases, thus a softer polymer is obtained. Besides, the density of the sulfur-based polymer is approximately 2067 kg/m3, and the thermal conductivity coefficient is measured at an average of 0.25 W/m·K. As the content of limonene in the polymer mixture raises, the thermal conductivity coefficient decreases and a more porous structure is formed.