Studies on the Stability and Optical Properties of Polymers Made from Sulfur

Abstract

Chapter 1: This study investigated the effect of the sulfur rank on the chemical characteristics of polymers produced by inverse vulcanisation. Using a novel and safe approach, six distinct sulfur polymers were produced. These polymers were investigated by changing the quantities of sulfur and alkene in the mixture. A wide range of microstructural analyses, including SEM, EDX, STA, NMR, XRD, and FT-IR spectroscopy, validated the synthesis of poly (S-r-DIB). The results of the tests revealed that the polymer with the lower sulfur content had slightly higher chemical and thermal stability than the polymer with a higher sulfur ratio. Poly(S-rDIB) treated with pyridine yielded soluble material, and the rate of the reaction with pyridine depended on the sulfur content. The use of poly(S-r-DIB) with a higher sulfur rank (Rank ≥4) have better mercury uptake properties Chapter 2: A unique and risk-free method was employed to create cyclic trisulfide monomer. This monomer can be used as a precursor to a crosslinked polymer. The interesting aspect about this monomer is that it allows polysulfide polymers to be made from a single monomer through ring opening polymerisation, rather than through a copolymerisation with sulfur and an alkene. A variety of microstructural techniques, including SEM, EDX, DCS, NMR, XRD, and TGA, verified the monomer and polymer synthesis. Chapter 3: An optimization approach was developed for separating cyclic trisulfide monomer from S-DCPD oligomer by reduction reaction. This process could be considered as a way to recycle sulfur polymer. Polymerization of this monomer resulted in polysulfide polymer, and this was validated using SEM, EDX, DCS, XRD, GC-MS and TGA. Chapter 4: Using norbornadiene as a crosslink, a new sulfur polymer was successfully created. Polymer production was confirmed using a range of microstructural methods, including SEM, EDX, DCS, IR, XRD, GC-MS and TGA. Reduction reaction of the polymer was carried out to confirm that the sulfur reacted with the two double bonds in the alkene. To assess the transparency of these novel poly(S-r-NBD) films, long wave infrared (LWIR) imaging studies were carried out