Effects of olefin and acid stabilizers on the properties of insoluble sulfur

Highlights: • Insoluble sulfur(IS) was prepared using olefin and acid as stabilizers. • Both the olefin and acid stabilizers could improve the thermal stability of the IS. • The olefin stabilizers were superior to the acid stabilizers. • The stability mechanism of carboxyl group and CC was proposed. The effects of the polymerization conditions on the yield of insoluble sulfur were investigated by using olefin, such as the 1,-dodecene, 1,-tetradecene, 1,-octadecene as well as acids, such as the salicylic acid, lauric acid and the oleic acid as polymerization stabilizers. The properties of the as-prepared insoluble sulfur were characterized by mu-Raman spectrometer and differential scanning calorimetry (DSC). The results demonstrated that both the olefin and acid stabilizers could couple with the end groups of the IS, thus improved the thermal stability of the IS, and the olefin stabilizers were superior to the acid stabilizers. The stabilizing effect of oleic acid was the best for the acid stabilizers, and the CC in the oleic acid played a crucial role in the stabilization of the IS.