An Efficient Ring-Opening Copolymerization of Elemental Sulfur with Various Olefinic Compounds to Produce Thermoplastic Polymeric Sulfur: Synthesis and Characterization

Inverse vulcanization reaction is a copolymerization process that involves the interaction of elemental sulfur with alkenes at high temperatures to yield highly distinctive materials having high percentage content of sulfur. In this study, new polymeric sulfur compounds were synthesized via inverse vulcanization reaction in which elemental sulfur interacts with two different types of materials including thermoplastic polymers like amorphous Poly Alfa-Olefin (APAO) copolymer, and Ethylene-vinyl-acetate copolymer (EVA), while the second kind was thermoplastic rubber like styrene-butadiene-styrene copolymer (SBS), and rubber waste from MAC Carpet. The reaction occurred at 180 oC in the presence of bitumen as dissolving media. The polymeric sulfur products were chemically characterized by FTIR and XRD. Changes in the morphology of surfaces were examined by SEM. Thermal stability was also examined through DSC and TGA. Finally, dynamic mechanical properties were investigated using DMA. The result approved that all prepared polymeric sulfur have high stiffness, and the polymeric sulfur based on alfa olefin, and SBS have higher storage modulus than EVA, and Mac waste materials. Also, glass transition temperatures Tg of prepared polymerics sulfur were around 58 °C to 63 °C that confirms their high thermal resistance. Consequently selected synthesized materials succeeded as good elasticators for sulfur polymerization.