Thioglycidyl Methacrylate-Based Reactive Polyalkylene Sulfide Resin as an Alternative Substrate for the Reaction with Elemental Sulfur: Peculiarities of Synthesis, Thermodynamic and Mechanical Properties of Sulfur-Rich Plastics with High Adhesive Ten

The search for chemical and technological solutions to process cheap and available elemental sulfur to produce valuable multifunctional materials is one of the current challenging tasks. Instead of extensively used low-molecular-weight monomers, we proposed to use the original reactive polyalkylene sulfide resin as an alternative reagent containing pendant methacrylic groups. The use of a reactive viscous resin instead of monomers allows the syntheses to be carried out under reduced pressure conditions and high temperature, which allows volatile impurities and byproducts to be removed from the reaction zone. Peculiarities in the glass transition temperatures, heat capacities, and onsets of thermal degradation were addressed in the paper. Two glass transition temperatures were demonstrated to be the unique feature of the synthesized materials. This phenomenon was attributed to the enhanced chain mobility of the polyalkylene sulfide resin used, which was consequently expressed as a specific chain organization in the systems studied. Assuming the analysis of the literature data and the results presented in this work, it was concluded that in order to obtain more homogeneous materials less susceptible to undesirable aging, it is preferred to use the ratio of double bonds to sulfur, providing the formation of short cross-links consisting of 2–3 sulfur atoms. The materials obtained showed relatively high values of the onset of thermal degradation exceeding 270 °C and very high adhesion to glass and steel. In both cases, the adhesion tensile strength values exceeded 10 MPa. Furthermore, the obtained materials showed high chemical resistance to basic organic solvents.