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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
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Combining agriculture and energy industry waste products to yield recyclable, thermally healable copolymers of elemental sulfur and oleic acid
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,ZOSx(x= wt % sulfur, wherexis 8–99). TheZOSxmaterials ranged from sticky tars to hard solids at room temperature. TheZOSxcompositions were assessed by1H NMR spectrometry, FTIR spectroscopy, and elemental microanalysis. CopolymersZOS59‐99, 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
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- Award ID(s):
- 1708844
- PAR ID:
- 10460512
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science Part A: Polymer Chemistry
- Volume:
- 57
- Issue:
- 15
- ISSN:
- 0887-624X
- Page Range / eLocation ID:
- p. 1704-1710
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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