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The preparation of sulfur containing polymers from inexpensive, commodity sulfur base chemicals is an emerging field of polymer chemistry as a route to consume elemental sulfur generated from fossil fuel refining. Recently a new process, termed, sulfenyl chloride inverse vulcanization has been developed that exploits the high reactivity and miscibility of sulfur monochloride, (S2Cl2) with a broad range of allylic monomers to prepare soluble, high molar mass linear polymers, segmented block copolymers and crosslinked thermosets with greater synthetic precision than achieved using classical inverse vulcanization with elemental sulfur. However, the ring opening of episulfonium intermediates from this polymerization can proceed via Markovnikov, anti-Markovnikov, or alternative pathways resulting in complex regioisomeric microstructures, particularly when used with allylic ester monomers. Hence, to accelerate structural characterization of this new class of polyhalodisulfides prepared by the sulfenyl chloride inverse vulcanization process, we report on a detailed structural characterization to quantify the molar composition of regioisomeric units in these materials using NMR spectroscopy,focusing on sulfenyl chloride additions to allylic benzoate substrates. We report on a general methodologyusing one- and two-dimensional NMR spectroscopic techniques to enable direct integration of 2D NMRspectroscopic cross peaks to quantify the molar composition of regioisomeric units in 1,3-diallyl isophthalate(DAI) polymerized with S2Cl2, along with detailed studies on model compound reactions to detail the analytical methodology. 

Abstract The development of a low‐cost photopolymer resin to fabricate optical glass of high refractive index for plastic optics is reported. This new free radically polymerizable photopolymer resin, termed, disulfide methacrylate resin (DSMR) is synthesized by the direct addition of allyl methacrylate to a commodity sulfur petrochemical, sulfur monochloride (S₂Cl₂). The rapid rates of free radical photopolymerization confer significant advantages in preparing high‐quality, bulk optical glass. The low‐cost, optical glass produced from this photopolymer possesses a desirable combination of high refractive index (n ≈ 1.57–1.59), low birefringence (Δn < 10⁻⁴), high glass transition values (T_g ≈ 100 °C), along with optical transparency rivaling, or exceeding that of poly(methyl methacrylate) (PMMA) as indicated by very low optical absorption coefficients (α < 0.05 cm⁻¹at 1310 nm) measured for thick glass DSMR photopolymer samples (diameter (D) = 25 mm; thickness = 1–30 mm). The versatile manufacturability of DSMR photopolymers for both molding and diamond turn machining methods is demonstrated to prepare precision optics and nano‐micropatterned arrays. Finally, large‐scale 3D printing vat photopolymerization of DSMR using high‐area rapid printing digital light processing additive manufacturing is demonstrated. 

Abstract The production of elemental sulfur from petroleum refining has created a technological opportunity to increase the valorization of elemental sulfur by the creation of high‐performance sulfur based plastics with improved thermomechanical properties, elasticity and flame retardancy. We report on a synthetic polymerization methodology to prepare the first example of sulfur based segmented multi‐block polyurethanes (SPUs) and thermoplastic elastomers that incorporate an appreciable amount of sulfur into the final target material. This approach applied both the inverse vulcanization of S₈with olefinic alcohols and dynamic covalent polymerizations with dienes to prepare sulfur polyols and terpolyols that were used in polymerizations with aromatic diisocyanates and short chain diols. Using these methods, a new class of high molecular weight, soluble block copolymer polyurethanes were prepared as confirmed by Size Exclusion Chromatography, NMR spectroscopy, thermal analysis, and microscopic imaging. These sulfur‐based polyurethanes were readily solution processed into large area free standing films where both the tensile strength and elasticity of these materials were controlled by variation of the sulfur polyol composition. SPUs with both high tensile strength (13–24 MPa) and ductility (348 % strain at break) were prepared, along with SPU thermoplastic elastomers (578 % strain at break) which are comparable values to classical thermoplastic polyurethanes (TPUs). The incorporation of sulfur into these polyurethanes enhanced flame retardancy in comparison to classical TPUs, which points to the opportunity to impart new properties to polymeric materials as a consequence of using elemental sulfur.