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Abstract The development of an organic optical glass, termed, disulfide glass (DSG), is reported as a new polymer for commodity plastic optics and thin film photonic applications. This low‐cost thermoset polymer possesses excellent transparency across the visible and infrared spectrum comparable to the best optical plastic to date, poly(methyl methacrylate), while having superior refractive index (n≈ 1.6). DSG can be fabricated into defect‐free, thick optical glass by bulk addition polymerization of two commodity monomers (sulfur monochloride, 1,3,5‐triallyl isocyanurate) via a new polymerization, sulfenyl chloride inverse vulcanization. The robust mechanical properties and optical clarity of DSG enable fabrication of precision optics (lenses, prisms) via diamond turn machining to demonstrate the manufacturability of DSG for commodity plastic optics. Finally, the synthetic modularity of DSG is demonstrated to form solution processable forms for the fabrication of thin film polymer photonic devices, negative tone polymer photoresists, and micropatterned arrays. 

Abstract In this study, the first fabrication of phase‐shifted Bragg gratings utilizing chalcogenide hybrid inorganic/organic polymers (CHIPs) is presented based on poly(sulfur‐random‐(1,3‐isopropenylbenzene) to measure the thermo‐optic coefficient (TOC) of this new class of optical polymers. The unique properties ofCHIPs, such as high index contrast and low optical losses, are leveraged to fabricate Bragg gratings that enable precise determination of the TOC and glass transition temperature (T_g) of these polymers. The optical measurement introduces a novel technique to measure the TOC and T_gof optical polymers which can be difficult to determine using traditional methods such as differential scanning calorimetry (DSC) after fabrication into photonic device constructs. The findings demonstrate thatCHIPs exhibit low thermo‐optic (TO) effects, making them exceptionally well‐suited for the development of thermally stable photonic integrated circuits. 

Abstract Multiple relaxation times are used to capture the numerous stress relaxation modes found in bulk polymer melts. Herein, inverse vulcanization is used to synthesize high sulfur content (≥50 wt%) polymers that only need a single relaxation time to describe their stress relaxation. The S-S bonds in these organopolysulfides undergo dissociative bond exchange when exposed to elevated temperatures, making the bond exchange dominate the stress relaxation. Through the introduction of a dimeric norbornadiene crosslinker that improves thermomechanical properties, we show that it is possible for the Maxwell model of viscoelasticity to describe both dissociative covalent adaptable networks and living polymers, which is one of the few experimental realizations of a Maxwellian material. Rheological master curves utilizing time-temperature superposition were constructed using relaxation times as nonarbitrary horizontal shift factors. Despite advances in inverse vulcanization, this is the first complete characterization of the rheological properties of this class of unique polymeric material. 

Abstract The development of infrared (IR) plastic optics for infrared thermal imaging, particularly, in the long‐wave IR (LWIR) spectrum (7–14 µm) is an area of growing technological interest due to the potential advantages associated with plastic optics (e.g., moldability and low cost). The development of a new class of optical polymers, chalcogenide‐based inorganic/organic hybrid polymers (CHIPs) derived from the inverse vulcanization of elemental sulfur, has enabled significant improvements in IR transparency due to reduction of IR absorbing organic comonomer units. The vast majority of effort has focused on new chalcogenide hybrid polymer synthesis and optical property improvements (e.g., refractive index, Abbe number, and LWIR transmission); however, fabrication and IR imaging methodology to prepare optical components has not been demonstrated, which remains critical to develop viable IR plastic optics. A new methodology is reported to fabricate optical components and evaluate LWIR imaging performance of this emerging class of optical polymers. New diffractive flat optics with a Fresnel lens design for these materials have been developed, along with a basic LWIR imaging system to evaluate CHIPs for LWIR imaging. This system‐based approach enables correspondence of copolymer structure‐property correlations with LWIR imaging performance, along with demonstration of room temperature LWIR imaging. 

Abstract In this concept review, the fundamental and polymerization chemistry of inverse vulcanization for the preparation of statistical and segmented sulfur copolymers, which have been actively developed and advanced in various applications over the past decade is discussed. This concept review delves into a discussion of step‐growth polymerization constructs to describe the inverse vulcanization process and discuss prepolymer approaches for the synthesis of segmented sulfur polyurethanes. Furthermore, this concept review discusses the advantages of inverse vulcanization in conjunction with dynamic covalent polymerization and post‐polymerization modifications to prepare segmented block copolymers with enhanced thermomechanical and flame retardant properties of these materials. 

Abstract Organosulfur polymers prepared via the inverse vulcanization of elemental sulfur with olefinic comonomers represent a new class of high‐chalcogenide content organic/inorganic macromolecules. Extensive reporting on new synthetic advances and materials derived from the inverse vulcanization process have been explored in the past decade. However, detailed structural analysis of these sulfur copolymers have not been rigorously conducted, due to the poor solubility of many of these materials, coupled with the numerous side‐reactions that result in complex microstructures from these synthetic methods. In the current report, we revisit analysis of the solution¹³C NMR spectral data for poly(S‐r‐Sty) and identify for the first time previously unidentified carbon peaks that offer new insights into a corrected repeating unit structure of this sulfur copolymer. 

Chalcogenide hybrid inorganic/organic polymers (CHIPs) are a new class of optical polymeric materials for imaging and photonic applications due to their high refractive indices and high optical transmission at visible and infrared wavelengths. In this study, we characterize these polymers to study the refractive index and delve into the electronic properties by way of measurements of their dielectric constants. Ellipsometry is used to determine the refractive indices for wavelengths from 500 nm to 12 µm, while we use capacitance measurements on thin film capacitors with a range of areas to find the dielectric constant. The results are in line with expectations based on the sulfur composition of the polymers-indices range from 1.7 to 1.85, and dielectric constants range from 2.6 to 3. With these measurements, these sulfur polymer materials are established to be good candidates for optical and photonic applications, particularly with respect to telecommunications. The dielectric constants suggest that applications such as electro-optic devices and capacitors may also be viable.