45807442
Mechanical and Electrical Properties of Sulfur-Containing Polymeric Materials Prepared via Inverse Vulcanization †
Recently, new methods have been developed for the utilization of elemental sulfur as a feedstock for novel polymeric materials. One promising method is the inverse vulcanization, which is used to prepare polymeric structures derived from sulfur and divinyl comonomers. However, the mechanical and electrical properties of the products are virtually unexplored. Hence, in the present study, we synthesized a 200 g scale of amorphous, hydrophobic as well as translucent, hyperbranched polymeric sulfur networks that provide a high thermal resistance (>220 °C). The polymeric material properties of these sulfur copolymers can be controlled significantly by varying the monomers as well as the feed content. The investigated comonomers are divinylbenzene (DVB) and 1,3-diisopropenylbenzene (DIB). Plastomers with low elastic content and high shape retention containing 12.5%–30% DVB as well as low viscose waxy plastomers with a high flow behavior containing a high DVB content of 30%–35% were obtained. Copolymers with 15%–30% DIB act, on the one hand, as thermoplastics and, on the other hand, as vitreous thermosets with a DIB of 30%–35%. Results of the thermogravimetric analysis (TGA), the dynamic scanning calorimetry (DSC) and mechanical characterization, such as stress–strain experiments and dynamic mechanical thermal analysis, are discussed with the outcome that they support the assumption of a polymeric cross-linked network structure in the form of hyper-branched polymers.
93642329
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.
205289038
Under sulfur's spell.
Thomas Rauchfuss marvels at the diversity of sulfur reactivity. Although it poisons most industrial catalysts, it adopts many forms in nature and takes on a variety of biological roles — including that of a biocatalyst.
1944535
The use of elemental sulfur as an alternative feedstock for polymeric materials.
An excess of elemental sulfur is generated annually from hydrodesulfurization in petroleum refining processes; however, it has a limited number of uses, of which one example is the production of sulfuric acid. Despite this excess, the development of synthetic and processing methods to convert elemental sulfur into useful chemical substances has not been investigated widely. Here we report a facile method (termed 'inverse vulcanization') to prepare chemically stable and processable polymeric materials through the direct copolymerization of elemental sulfur with vinylic monomers. This methodology enabled the modification of sulfur into processable copolymer forms with tunable thermomechanical properties, which leads to well-defined sulfur-rich micropatterned films created by imprint lithography. We also demonstrate that these copolymers exhibit comparable electrochemical properties to elemental sulfur and could serve as the active material in Li-S batteries, exhibiting high specific capacity (823 mA h g(-1) at 100 cycles) and enhanced capacity retention.
101216664
Inverse Vulcanization of Elemental Sulfur to Prepare Polymeric Electrode Materials for Li–S Batteries
Sulfur-rich copolymers based on poly(sulfur-random-1,3-diisopropenylbenzene) (poly(S-r-DIB)) were synthesized via inverse vulcanization to create cathode materials for lithium–sulfur battery applications. These materials exhibit enhanced capacity retention (1005 mAh/g at 100 cycles) and battery lifetimes over 500 cycles at a C/10 rate. These poly(S-r-DIB) copolymers represent a new class of polymeric electrode materials that exhibit one of the highest charge capacities reported, particularly after extended charge–discharge cycling in Li–S batteries.
96660600
Kilogram scale inverse vulcanization of elemental sulfur to prepare high capacity polymer electrodes for Li‐S batteries
The synthesis of high content sulfur copolymers via the inverse vulcanization of elemental sulfur and 1,3-diisopropenylbenzene (DIB) on a one-kilogram scale is reported in a single step process. Investigation into the effects of temperature, reaction scale, and comonomer feed ratios on the inverse vulcanization process of S8 and DIB were explored to suppress the Trommsdorf effect and enable large scale synthesis of these copolymers. The copolymers were then successfully used as the active cathode materials in Li-S batteries, exhibiting enhanced capacity retention and battery lifetimes (608 mAh/g at 640 cycles) at a C/10 rate. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 173–177
99571921
Inverse vulcanization of sulfur with divinylbenzene: Stable and easy processable cathode material for lithium-sulfur batteries
Abstract Lithium-Sulfur (Li-S) battery technology is one of the promising candidates for next generation energy storage systems. Many studies have focused on the cathode materials to improve the cell performance. In this work we present a series of poly (S-DVB) copolymers synthesised by inverse vulcanization of sulfur with divinylbenzene (DVB). The poly (S-DVB) cathode shows excellent cycling performances at C/2 and C/4 current rates, respectively. It was demonstrated poly (S-DVB) copolymer containing 20% DVB did not influence the electrochemical performance of the sulfur material, compared to elemental sulfur as high specific capacities over ∼700 mAh g −1  at 500 cycles were achieved at C/4 current rate, comparable to conventional carbon-based S cathodes. However, the use of copolymer network is assumed to act firstly as sulfur reservoir and secondly as mechanical stabilizer, enhancing significantly the cycling lifetime. The Li-poly (S-DVB) cell demonstrated an extremely low degradation rate of 0.04% per cycle achieving over 1600 cycles at C/2 current rate.
101248451
Inverse vulcanization of bismaleimide and divinylbenzene by elemental sulfur for lithium sulfur batteries
Abstract A novel approach to fabricate sulfur rich thermosets as materials for Li S batteries is described. For this purpose, polybismaleimide copolymers were synthesized by reacting bismaleimide (BMI) monomer and elemental sulfur at 180 °C. Parameters such as monomers and feed ratios on the polymerization were studied. Divinylbenzenes were also used in the formulation to increase sulfur feed ratios up to 70 wt%. The thermal stability of the copolymers was also investigated by using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). BMI based copolymers had shown excellent thermal stability and yielded up to 40% char yield at 800 °C. The obtained insoluble copolymers were used in Li S battery applications. Thus, galvanostatic discharge–charge experiments were carried out to evaluate the electrochemical performance of these materials. Both 30% sulfur containing, poly(S-BMI)30%, and 70% sulfur containing, Poly(S-BMI-DVB)70%, composites exhibited a staircase voltage profile which is typical for Li S batteries. These materials, as Li S battery cathodes, demonstrated around 400 mA h/g specific capacities at 50 cycles.
100340344
Inverse vulcanization of elemental sulfur and styrene for polymeric cathodes in Li-S batteries
High sulfur content copolymers were prepared via the inverse vulcanization of elemental sulfur with styrene. This reaction was carried out at a relatively low temperature and invokes a new chain transfer mechanism of abstraction of benzylic protons to form stable copolymers. The use of styrene as a comonomer for inverse vulcanization was attractive due to the low cost and wide spread industrial use of styrenics in free radical processes. The copolymers were used as the active cathode material in Li-S batteries that exhibited outstanding device performance, maintaining 489 mAh/g capacity after 1000 cycles. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 107–116
98694924
Inverse vulcanization of elemental sulfur with 1,4-diphenylbutadiyne for cathode materials in Li–S batteries
High sulfur content copolymers were prepared via inverse vulcanization of sulfur with 1,4-diphenylbutadiyne (DiPhDY) for use as the active cathode material in lithium–sulfur batteries. These sulfur-rich polymers exhibited excellent capacity retention (800 mA h g−1 at 300 cycles) and extended battery lifetimes of over 850 cycles at C/5 rate.
95898856
One-pot synthesis of PbS NP/sulfur-oleylamine copolymer nanocomposites via the copolymerization of elemental sulfur with oleylamine
A novel synthetic and processing strategy for converting elemental sulfur into polymeric and nanocomposite materials is reported. We describe a facile one-pot reaction using elemental sulfur and oleylamine as comonomers to prepare high sulfur content copolymers and lead sulfide nanoparticle (PbS NP) nanocomposites. This process enables the preparation of solution processable copolymers and nanocomposites, where the loading and dispersion of PbS NP inclusions could be precisely controlled. We demonstrate the dual roles of oleylamine with sulfur for both the copolymerization of sulfur copolymers as well as the in situ synthesis of PbS NPs in a one-pot fashion.
205938059
Nanoparticle-sulphur "inverse vulcanisation" polymer composites.
Composites of sulphur polymers with nanoparticles such as PbS, with tunable optical properties are reported. A hydrothermal route incorporating pre-formed nanoparticles was used, and their physical and chemical properties evaluated by transmission and scanning electron microscopy, thermogravimetric and elemental analyses. These polymers are easily synthesised from an industrial waste material, elemental sulphur, can be cast into virtually any form and as such represent a new class of materials designed for a responsible energy future.
97614085
High refractive index polyvinylsulfide materials prepared by selective radical mono-addition thiol–yne chemistry
We report on a new framework for preparing high-refractive index polymeric materials which combines the selective thiol radical mono-addition to phenyl-acetylene derivatives with hyperbranched architectures. Using this strategy we have synthesized a series of linear and hyperbranched polyvinyl sulfide (PVS) materials, employing different dithiol (A2 and A′2) and di- and trialkyne (B2 and B3) monomers. The process requires only a simple radical initiator, such as AIBN, in lieu of expensive or toxic catalysts and this chemistry produces polymers in high yield (up to 96%) and high molecular weight (up to 123 000 g mol−1). The polymers are optically transparent, thermally stable (up to 420 °C) and readily form high-quality films. The end group composition of the hyperbranched materials can be easily adjusted by changing the A2/B3 feed ratio. The sulfur incorporation and conjugation resulting from thiol–yne coupling with selective mono-addition results in materials with high refractive indices in the visible and IR region (nD = 1.68–1.75) and optical dispersions as low as 0.004. Moreover, we demonstrate that the hyperbranched architecture produces materials with better performance in terms of light reflection and chromatic dispersion compared to linear structures.
97684538
High refractive index polymers: fundamental research and practical applications
Rapid developments in advanced photonic devices have led to the increasing exploration of high refractive index (high-n) materials, particularly high-refractive-index polymers (HRIP). High refractive indices have been achieved either by introducing substituents with high molar refractions to make intrinsic HRIPs or by combining high-nnanoparticles with polymer matrixes to make HRIP nanocomposites. For intrinsic HRIPs, aromatic rings, sulfur-containing groups, halogens except fluorine and organometallic moieties are often utilized to increase their refractive indices. However, their upper n limitation is usually below 1.80. Incorporation of high-nnanoparticles into polymers seems to be a more promising strategy to achieve a refractive index higher than 1.80; however, the obtained organic–inorganic hybrid materials sometimes suffer from poor storage stability, higher optical loss and poor processability. Besides the refractive index, optical dispersion (Abbe number), birefringence and optical transparency are often involved in designing HRIPs for practical optical fabrications. Therefore, research of HRIPs is becoming an interdisciplinary subject. This feature article reviews recent developments in optical HRIPs and their typical applications in high-tech fields.
40694680
The chemistry of organic polysulfanes R-S(n)-R (n > 2).
III. Structures of Organic Polysulfanes 3922 A. General 3922 B. Structures of Chain-Like R−Sn−R Molecules 3923 C. Structures of Cyclic R−Sn−R Molecules 3924 D. Conformational Studies 3925 IV. Analysis of Organic Polysulfanes 3925 A. General 3925 B. NMR Spectroscopy 3926 C. Chromatography 3926 D. Raman Spectroscopy 3928 E. XANES Spectroscopy 3928 V. Reactions of Organic Polysulfanes 3928 A. Interconversion Reactions 3928 B. Sulfur Transfer Reactions 3930 C. Replacement Reactions 3931 D. Nucleophilic Displacement Reactions at the Sulfur−Sulfur Bond 3931
100056879
Porous carbons from inverse vulcanised polymers
Elemental sulfur is an underutilised industrial by-product. It has been recently shown that it can be simply and scalably co-polymerised, by “inverse vulcanisation” with organic crosslinkers. The properties of porous carbons, which have extensive uses in science and industry, are influenced by the materials from which they are generated. Reported here are the first examples of porous carbons produced from high-sulfur inverse vulcanised polymers. The materials produced show micro-porosity, gas selectivity, and are doped with sulfur. The simplicity of the technique, and wide range of other potential inverse vulcanised feedstocks, gives scope for transferability and control of properties.
35870890
Porous inverse vulcanised polymers for mercury capture.
Supercritical carbon dioxide is used to generate macroporosity in an inverse vulcanised polymer, which shows excellent promise for enhanced mercury capture and filtration from water.
55370309
Low cost and renewable sulfur-polymers by inverse vulcanisation, and their potential for mercury capture
Sulfur is not only a highly abundant element, but also produced as a by-product of the petrochemicals industry. However, it has not been conventionally used to produce functional materials because polymeric sulfur is unstable, and decomposes back to its monomer. Recently, inverse vulcanisation has been used to produce stable polymeric materials with elemental sulfur as a major component. Here we report a series of alternative crosslinkers for inverse vulcanisation that are either low-cost industrial byproducts, or bio-derived renewables. These are shown to produce stable polymers with superior properties to previously reported materials. When made porous by the action of supercritical carbon dioxide or salt templating, these high sulfur polymers show excellent potential for mercury capture and filtration.
96546685
Chemistry of the modification of sulphur by the use of dicyclopentadiene and of styrene
Dicyclopentadiene reacts with excess sulphur in the melt at 140°C to give initially cyclic tri- and pentathianes which then copolymerise with further sulphur to give initially chain polymers and then finally cross-linked species, Styrene reacts under the same conditions to give rapid initial formation of relatively high molecular weight polymeric polysulphides which then depolymerise to give a mixture of short chain species and 2,4-diphenylthiophene.
93588223
Copolymerization of elemental sulfur with cyclic(arylene disulfide) oligomers
Copolymerization reactions between cyclic(arylene disulfide) oligomers were studied. The cyclic disulfide oligomers derived from 4,4′-isopropylidene bisbenzenethiol gave soluble polysulfanes via copolymerization with S8. The copolymerization reactions were studied both in solution and melt by GPC and NMR. Solution copolymerization reactions can only form polysulfanes with up to three to four sulfur linkages; however, melt copolymerization reactions gave polysulfanes with up to seven sulfur linkages (average). The melt copolymerization reactions between cyclic disulfide oligomers derived from 4,4′-thiobis(benzenethiol) and S8 were studied using DSC, TGA, and DMTA. With increasing contents of sulfur in the polysulfanes, Tgs, 5% weight losses by TGA, and tan δ decreased. With seven sulfur linkages in the polymer, it is a rubber with a Tg of 12°C, a 5% weight loss by TGA of 249°C, and tan δ of 44°C, respectively. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2961–2968, 1997
93011782
Anionic copolymerisation of elemental sulfur with 2,2-dimethylthiirane
The copolymerization of elemental sulfur (2) with 2,2-dimethylthiirane (1), initiated with sodium thiophenolate in benzene solution was studied. By 1H NMR and laser Raman spectroscopy of the resulting copolymers 3 it could be shown that true copolymers with short polysulfide chains are formed and that starting with a sufficiently large ratio of 2/1 diads of 1 are absent.
102250090
Elemental sulfur‐based polymeric materials: Synthesis and characterization
New elemental sulfur-based polymeric materials called poly(sulfur-random-divinylbenzene) [poly(S-r-DVB)] were synthesized by ring opening polymerization via inverse vulcanization technique in the presence of a mixture of o-, m-, and p-diviniylbenzene (DVB) as a cross-linker. A clear yellow/orange colored liquid was obtained from the elemental sulfur melted at 160 °C and then by adding various amounts of DVB to this liquid directly via a syringe at 200 °C viscous reddish brown polymeric materials were obtained. The copolymers are soluble in common solvents like tetrahydrofuran, dichloromethane, and chloroform, and they can be coated on any surface as a thin film by a spray coating technique. The characterization of the materials was performed by using nuclear magnetic resonance, fourier transform infrared, and Raman spectroscopies. The morphological properties were monitored via scanning electron microscope technique. Thermal analysis showed that an increase in the amount of DVB in the copolymers resulted in an increase in the thermal decomposition temperature. On the other hand, poly(S-r-DVB) copolymers exhibited good percent transmittance as 50% T between 1500 and 13,000 nm in electromagnetic radiation spectrum, which makes them good candidates to be amenable use in military and surveillance cameras. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43655.
97026821
The effect of polymer surface on the wetting and adhesion of liquid systems
Young's equation describes the wetting phenomenon in terms of the contact angle between a liquid and a solid surface. However, the contact angle is not the only parameter that defines liquid–solid interactions, an additional parameter related to the adhesion between the liquid drop and the solid surface is also of importance in cases where liquid sliding is involved. It is postulated that wetting which is related to the contact angle, and interfacial adhesion, which is related to the sliding angle, are interdependent phenomena and have to be considered simultaneously. A variety of models that relate the sliding angle to the forces developed along the contact periphery between a liquid drop and a solid surface have been proposed in the literature. Here, a modified model is proposed that quantifies the drop-sliding phenomenon, based also on the interfacial adhesion that develops across the contact area of the liquid/solid interface. Consequently, an interfacial adhesion strength parameter can be defined depending on the mass of the drop, the contact angle and the sliding angle. To verify the proposed approach the adhesion strength parameter has been calculated, based on experimental results, for a number of polymer surfaces and has been correlated with their composition and structure. The interaction strength parameter can be calculated for any smooth surface from measurements of the contact and the sliding angles.
117081687
Principles of Physics
Volume I: Introduction and Vectors. Motion in One Dimension. Motion in Two Dimensions. The Laws of Motion. More Applications of Newton's Laws. Work and Energy. Potential Energy and Conservation of Energy. Momentum and Collisions. Relativity. Rotational Motion. Orbital Motions and the Hydrogen Atom. Oscillatory Motion. Wave Motion. Superposition and Standing Waves. Fluid Mechanics. Volume II: Temperature and the Kinetic Theory of Gases. Heat and the First Law of Thermodynamics. Heat Engines, Entropy, and the Second Law of Thermodynamics. Electric Forces and Electric Fields. Electric Potential and Capacitance. Current and Direct Current Circuits. Magnetism. Induced Voltages and Inductance. Electromagnetic Waves. Reflection and Refraction of Light. Mirrors and Lenses. Wave Optics. Quantum Physics. Atomic Physics. Nuclear Physics. Particle Physics and Cosmology. Appendices.
102362761
Dynamic Covalent Polymers via Inverse Vulcanization of Elemental Sulfur for Healable Infrared Optical Materials
We report on dynamic covalent polymers derived from elemental sulfur that can be used as thermally healable optical polymers for mid-IR thermal imaging applications. By accessing dynamic S–S bonds in these sulfur copolymers, surface scratches and defects of free-standing films of poly(sulfur-random-1,3-diisopropenylbenzene) (poly(S-r-DIB) can be thermally healed, which enables damaged lenses and windows from these materials to be reprocessed to recover their IR imaging performance. Correlation of the mechanical properties of these sulfur copolymers with different curing methods provided insights to reprocess damaged samples of these materials. Mid-IR thermal imaging experiments with windows before and after healing of surface defects demonstrated successful application of these materials to create a new class of “scratch and heal” optical polymers. The use of dynamic covalent polymers as healable materials for IR applications offers a unique advantage over the current state of the art (e.g., germanium or ...