Electrochemical Synthesis of Poly(trisulfides)

Abstract

With increasing interest in high sulfur content polymers, there is a need to develop new methods for their synthesis that feature improved safety and control of structure. In this report, electrochemically initiated ring-opening polymerization of norbornene-based cyclic trisulfide monomers delivered well-defined, linear poly(trisulfides), which were solution processable. Electrochemistry provided a controlled initiation step that obviates the need for hazardous chemical initiators. The high temperatures required for inverse vulcanization are also avoided resulting in an improved safety profile. Density functional theory calculations revealed a reversible "self-correcting" mechanism that ensures trisulfide linkages between monomer units. This control over sulfur rank is a new benchmark for high sulfur content polymers and creates opportunities to better understand the effects of sulfur rank on polymer properties. Thermogravimetric analysis coupled with mass spectrometry revealed the ability to recycle the polymer to the cyclic trisulfide monomer by thermal depolymerization. The featured poly(trisulfide) is an effective gold sorbent, with potential applications in mining and electronic waste recycling. A water-soluble poly(trisulfide) containing a carboxylic acid group was also produced and found to be effective in the binding and recovery of copper from aqueous media.

Step‐growth Polymerization of Aziridines with Elemental Sulfur: Easy Access to Linear Polysulfides and Their Use as Recyclable Adhesives

“…[18] Chalker et al reported an electrochemically initiated polymerization of cyclic trisulfides, leading to linear poly(trisulfides) (Figure 1C). [19] Char et al utilized allyl glycidyl ether as a comonomer to produce polysulfides with enhanced mechanical properties, expanding the scope of monomers. [20] Furthermore, Quan et al introduced a photoinduced inverse vulcanization process that operates at ambient temperature and does not generate toxic gases.…”

“…reported an electrochemically initiated polymerization of cyclic trisulfides, leading to linear poly(trisulfides) (Figure 1C). [19] Char et al. utilized allyl glycidyl ether as a comonomer to produce polysulfides with enhanced mechanical properties, expanding the scope of monomers [20] .…”

Diverse Side-Chain Transformation of High Refractive Index Methylthio-Substituted Poly(phenylene sulfide)s

“…Sulfur-containing polymers (SCPs) have been extensively employed in various functional polymers, encompassing energy-related, − self-healing, metal-removal, , and optical applications. These intriguing properties can generally be attributed to the unique polarizable features of sulfur atoms, with SCPs being particularly applied in developing high refractive index polymers (HRIPs). − For visible-light optoelectronic applications, such as encapsulants for light-emitting diodes (LEDs) and light-emitting electrochemical cells (LECs), − HRIPs with a high RI (generally 1.7–1.8) and adequate transparency at a few micrometer thickness are essential …”

Base-Assisted Polymerizations of Elemental Sulfur and Alkynones for Temperature-Controlled Synthesis of Polythiophenes or Poly(1,4-dithiin)s

“…The sharp contrast of the large production and its limited consumption has resulted in great surplus of sulfur, which has become a global concern because the flammable nature of sulfur and its slow oxidation to SO x in air have caused serious safety issues and environmental problems such as acid rain. , It is hence of great significance both in academia and in industry to develop economic and efficient methods to synthesize sulfur-containing profitable polymers from elemental sulfur. Tremendous efforts have been devoted to utilizing sulfur in polymer synthesis, such as the preparation of chalcogenide hybrid inorganic/organic polymers (CHIPs) through inverse vulcanization involving high temperature, ,− Zn­(DTC) 2 catalyst, or ultraviolet light, and the ambiguous structures and poor solubility of the products remained challenging. To control the product structures, sulfur-containing monomers such as S 2 Cl 2 and norbornene-based cyclic trisulfide derived from elemental sulfur were utilized as the alternative monomer feedstocks for polymerization .…”