Network polymers of sulfur and poly(4-allyloxystyrene), PAOSx ( x = percent by mass sulfur, where x is varied from 10–99), were prepared by reaction between poly(4-allyloxystyrene) with thermal homolytic ring-opened S 8 in a thiol-ene-type reaction. The extent to which sulfur content and crosslinking influence thermal/mechanical properties was assessed. Network materials having sulfur content below 50% were found to be thermosets, whereas those having >90% sulfur content are thermally healable and remeltable. DSC analysis revealed that low sulfur-content materials exhibited neither a T g nor a T m from −50 to 140 °C, whereas higher sulfur content materials featured T g or T m values that scale with the amount of sulfur. DSC data also revealed that sulfur-rich domains of PAOS90 are comprised of sulfur-crosslinked organic polymers and amorphous sulfur, whereas, sulfur-rich domains in PAOS99 are comprised largely of α-sulfur (orthorhombic sulfur). These conclusions are further corroborated by CS 2 -extraction and analysis of extractable/non-extractable fractions. Calculations based on TGA, FT-IR, H 2 S trapping experiments, CS 2 -extractable mass, and elemental combustion microanalysis data were used to assess the relative percentages of free and crosslinked sulfur and average number of S atoms per crosslink. Dynamic mechanical analyses indicate high storage moduli for PAOS90 and PAOS99 (on the order of 3 and 6 GPa at −37 °C, respectively), with a mechanical T g between −17 °C and 5 °C. A PAOS99 sample retains its full initial mechanical strength after at least 12 pulverization-thermal healing cycles, making it a candidate for facile repair and recyclability.
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Facile route to an organosulfur composite from biomass-derived guaiacol and waste sulfur
A simple approach to a high sulfur-content material from biomass-derived guaiacol and waste sulfur is introduced. This direct reaction of elemental sulfur with an anisole derivative lacking olefins or halogen leaving groups expands the monomer scope beyond existing routes to high sulfur-content materials.
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- Award ID(s):
- 1708844
- NSF-PAR ID:
- 10199256
- Date Published:
- Journal Name:
- Journal of Materials Chemistry A
- Volume:
- 8
- Issue:
- 39
- ISSN:
- 2050-7488
- Page Range / eLocation ID:
- 20318 to 20322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d0ta07465a
