Sulfurization of Polymers: A Novel Access to Electroactive and Conducting Materials

Abstract

The article is a concise analysis of the author's group's systematic exploration of the scope and potential of a new general approach to the synthesis of sulfur-rich polyconjugated polymers by direct dehydrogenative sulfurization of common polymers (polyethylene, polyacetylene, polystyrene, polyvinylpyridine, polydiethylsiloxane) with elemental sulfur. The deeply sulfurized polymers thus formed, consist of functionalized redox-active polyene, polysulfide and polycondensed thiophene entities and related blocks, the ratio of which depends on the reaction conditions and starting polymer structure. This paves the simplest way to electroactive and conducting materials with tailor-made properties, which may find application (among others) as principal cathode components of advanced electrochemical energy storage devices, e.g. lithium rechargeable batteries.

Melt processed elemental sulfur reinforced polyethylene composites

“…High density polyethylene (HDPE) was used as host matrix because it is widely used thermoplastic for many engineering applications and it is chemically inert. Additionally, our aim is to use elemental sulfur as reinforcing agent without inducing classical vulcanization or sulfurization reactions . We have characterized the composites to understand the chemistry of sulfur in the host matrix as well as the thermal and mechanical properties of the composites.…”

Structure Evolution in Polyethylene‐Derived Carbon Fiber Using a Combined Electron Beam‐Stabilization‐Sulphurization Approach

“…Also, since the stabilization process of PE fibers occurs at temperatures above the melting point of PE, i.e., above 130 °C, the precursor must be cross‐linked in order to withstand the temperatures and to prevent fiber fusing or even melting. Few successful dehydrogenation methods have been reported so far and comprise the transfer dehydrogenation by a dihydrido iridium pincer complex, [ 40 ] halogenation/dehalogenation, [ 41 ] sulfonation with SO 3 [ 42–49 ] and the ammoxidation of PE. [ 50 ] All these approaches provide oxidized, dehydrogenated PE precursor fibers suitable for subsequent carbonization.…”

“…reported on molten elemental sulphur (mS 8 ) as oxidizing and dehydrogenation agent for bulk PE. [ 48,49 ] Reactions were run at 160–365 °C and reportedly resulted in a semi‐aromatic material, which was evaluated for use as electroactive and conducting powder. According to the authors, one sulphur atom per carbon atom is bound to the carbon chain via a double bond while most of the hydrogen is removed as H 2 S (Figure S6, Supporting Information).…”

Ethynedithiol‐based polyeneoligosulfides as active cathode materials for lithium‐sulfur batteries

“…Over the last decade, research in the development of new lithium‐sulfur rechargeable batteries has drawn attention to high sulfur content redox polymers as potential active components of cathode compositions 1–9. Among them, of a special interest, are electroconductive polymers, since, theoretically they should improve electrons transfer to the outer circuit 10…”