A study on the structure and properties of polymeric sulfur

The structure of insoluble sulfur prepared by quenching sulfur vapours, a polymeric sulfur allotrope used as non-blooming vulcanizing agent in the rubber industry, has been studied by X-ray diffraction of powders. The diffraction pattern has been compared with previous data taken on stretched plastic sulfur and fibrous sulfur prepared at very high pressures (30-60 kbar). The superstructures of stretched plastic sulfur and fibrous sulfur are shown to be similar to each other but different from that of insoluble sulfur used in the rubber industry. The FT-IR spectrum of insoluble sulfur has been reported in comparison with that of rhombic sulfur, showing that this technique is very useful for qualitative analysis of sulfur allotropes. The thermal behaviour of insoluble sulfur was studied by DSC and the heat of fusion and the melting point were determined in comparison with rhombic and monoclinic sulfur.