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The unique properties and sustainability advantages of sulfur polymer cement have led to efforts to use them as alternatives to traditional Portland cement. The current study explores the impact of environmental stresses on the strength development of polymer composite SunBG90, a material composed of animal and plant fats/oils vulcanized with 90 wt. % sulfur. The environmental stresses investigated include low temperature (−25 °C), high temperature (40 °C), and submersion in water, hexanes, or aqueous solutions containing strong electrolyte, strong acid, or strong base. Samples were analyzed for the extent to which exposure to these stresses influenced the thermo-morphological properties and the compressional strength of the materials compared to identical materials allowed to develop strength at room temperature. Differential scanning calorimetry (DSC) analysis revealed distinct thermos-morphological transitions in stressed samples and the notable formation of metastable γ-sulfur in hexane-exposed specimens. Powder X-ray diffraction confirmed that the crystalline domains identified by DSC were primarily γ-sulfur, with ~5% contribution of γ-sulfur in hexane-exposed samples. Compressive strength testing revealed high strength retention other than aging at elevated temperatures, which led to ~50% loss of strength. These findings reveal influences on the strength development of SunBG90, lending important insight into possible use as an alternative to OPC. 

High sulfur-content materials (HSMs) formed via inverse vulcanization of elemental sulfur with animal fats and/or plant oils can exhibit remarkable mechanical strength and chemical resistance, sometimes superior to commercial building products. Adding pozzolan fine materials—fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBFS), or metakaolin (MK)—can further improve HSM mechanical properties and stability. Herein, we detail nine materials comprised of rancidified chicken fat, elemental sulfur, and canola or sunflower oil (to yield CFS or GFS, respectively) and, with or without FA, SF, GGBFS, or MK. The base HSMs, CFS90 or GFS90, contained 90 wt% sulfur, 5 wt% chicken fat, and 5 wt% canola or sunflower oil, respectively. For each HSM/fine combination, the resulting material was prepared using a 95:5 mass input ratio of HSM/fine. No material exhibited water uptake >0.2 wt% after immersion in water for 24 h, significantly lower than the 28 wt% observed with ordinary Portland cement (OPC). Impressively, CFS90, GFS90, and all HSM/fine combinations exhibited compressive strength values 15% to 55% greater than OPC. After immersion in 0.5 M H2SO4, CFS90, GFS90, and its derivatives retained 90% to 171% of the initial strength of OPC, whereas OPC disintegrated under these conditions. CFS90, GFS90, and its derivatives collectively show promise as sustainable materials and materials with superior performance versus concrete. 

Ordinary Portland Cement (OPC) production consumes tremendous amounts of fresh water and energy and releases vast quantities of CO2 into the atmosphere. Not only would an alternative to OPC whose production requires no water, releases little CO2, and consumes less energy represent a transformative advance in the pursuit of industrial decarbonization, but the greater availability of safe drinking water would lead to significantly improved public health, particularly among vulnerable populations most at risk from contaminated water supply. For any OPC alternative to be adopted on any meaningful scale, however, its structural capabilities must meet or exceed those of OPC. An inverse vulcanization of brown grease, sunflower oil, and elemental sulfur (5:5:90 weight ratio) was successfully modified to afford the high-sulfur-content material SunBG90 in quantities > 1 kg, as was necessary for standardized ASTM and ISO testing. Water absorption (ASTM C140) and thermal conductivity (ISO 8302) values for SunBG90 (<1 wt% and 0.126 W·m−1·K−1, respectively) were 84% and 94% lower than those for OPC, respectively, suggesting that SunBG90 would be more resistant against freeze-thaw and thermal stress damage than OPC. Consequently, not only does SunBG90 represent a more environmentally friendly material than OPC, but its superior thermomechanical properties suggest that it could be a more environmentally robust material on its own merits, particularly for outdoor structural applications involving significant exposure to water and seasonal or day/night temperature swings. 

Abstract Rancid animal fats unsuitable for human or animal food production represent low‐value and abundant, yet underexploited organic chemical precursors. The current work describes a strategy to synthesize high sulfur‐content materials (HSMs) that directly utilizes a blend of partially hydrolyzed chicken fat and plant oils as the organic comonomers, following up on analogous reactions using brown grease in place of chicken fat. The reaction of sulfur and chicken fat with either canola or sunflower oil yielded crosslinked polymer composites CFS_xor GFS_x, respectively (x = wt% sulfur, varied from 85%–90%). The composites exhibited compressive strengths of 24.7–31.7 MPa, and flexural strengths of 4.1–5.7 MPa, exceeding the value of established construction materials like ordinary Portland cement (compressive strength ≥17 MPa required for residential building, flexural strength 2–5 MPa). The composites also exhibited thermal stability up to 215–224 °C. The simple single‐step protocol described herein represents a way to upcycle an affordable and previously unexploited animal fat resource to form structural composites via the atom economical inverse vulcanization mechanism. 

This paper is review with 119 references. Approaches to supplant currently used plastics with materials made from more sustainably-sourced monomers is one of the great contemporary challenges in sustainable chemistry. Fatty acids are attractive candidates as polymer precursors because they can be affordably produced on all inhabited continents, and they are also abundant as underutilized by-products of other industries. In surveying the array of synthetic approaches to convert fatty acids into polymers, those routes that produce organosulfur polymers stand out as being especially attractive from a sustainability standpoint. The first well-explored synthetic approach to fatty acid-derived organosulfur polymers employs the thiol-ene click reaction or the closely-related thiol-yne variation. This approach is high-yielding under mild conditions with up to 100% atom economy and high functional group tolerance. More recently, inverse vulcanization has been employed to access high sulfur-content polymers by the reaction of fatty acid-derived olefins with elemental sulfur. This approach is attractive not only because it is theoretically 100% atom economical but also because elemental sulfur is itself an underutilized by-product of fossil fuel refining. The thiol-ene, inverse vulcanization, and mechanistically-related thiol-yne and classic vulcanization are therefore discussed as promising routes to access polymers and composites from fatty acid-derived precursors. 

ABSTRACT Efforts to develop sustainable industrial processes have led to significant advances toward supplanting petrochemical‐dependent technologies. Some of these otherwise sustainable processes, notably animal product rendering and biodiesel production, produce low value waste that is high in free fatty acids. Sulfur in turn is a primary waste product of fossil fuel refining. In the current contribution, copolymers are prepared by reaction of elemental sulfur with fatty acids in several monomer ratios. Both monounsaturated oleic acid and bis(unsaturated) linoleic acid were evaluated to assess the extent to which copolymer properties relate to the degree of unsaturation of the fatty acid comonomer. Furthermore, copolymers prepared from technical grade versus pure linoleic acid were compared to evaluate the viability of the considerably more affordable technical grade monomer. The thermal and mechanical properties of the copolymers were assessed by thermogravimetric analysis, differential scanning calorimetry and dynamic mechanical analysis. © 2020 Wiley Periodicals, Inc. J. Polym. Sci.2020,58, 438–445 

ABSTRACT Sulfur and oleic acid, two components of industrial waste/byproducts, were combined in an effort to prepare more sustainable polymeric materials. Zinc oxide was employed to serve the dual role of compatibilizing immiscible sulfur and oleic acid as well as to suppress evolution of toxic H₂S gas during reaction at high temperature. The reaction of sulfur, oleic acid, and zinc oxide led to a series of composites,ZOS_x(x= wt % sulfur, wherexis 8–99). TheZOS_xmaterials ranged from sticky tars to hard solids at room temperature. TheZOS_xcompositions were assessed by¹H NMR spectrometry, FTIR spectroscopy, and elemental microanalysis. CopolymersZOS_59‐99, were further analyzed for thermal and mechanical properties by thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. Remarkably, evenZOS₉₉, comprising only 1 wt % of zinc oxide/oleic acid (99 wt % S) exhibits at least an eightfold increase in storage modulus compared to sulfur alone. The four solid samples (59–99 wt % S) were thermally healable and readily remeltable with full retention of mechanical durability. These materials represent a valuable proof‐of‐concept for sustainably sourced, recyclable materials from unsaturated fatty acid waste products. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1704–1710