A Decade Development of Inverse Vulcanization Towards Green and Sustainable Practices
Hang Shen, Botuo Zheng, Huagui Zhang
Abstract
Inverse vulcanization utilizes alkenyl monomers and elemental sulfur, an excessive by-product of oil and gas refineries, to synthesize dynamically crosslinked sulfur-rich polymers, therefore providing a new way to construct sustainable and versatile materials. The inverse vulcanization of the biological extracts and natural polymers gives rise to a variety of bio-based polysulfides aligning with the concept of green chemistry. In this paper, the development of synthesis strategies, corresponding mechanisms, scope of renewable cross-linking agents, and the properties as well as the potential applications of polysulfides are reviewed. In particular, the progress in the preparation of various polysulfides from fossil resources to bio-based counterparts is deliberated with multiple modification methods elucidated. The bio-derived polysulfides are proved to be outstanding materials and prominent alternatives for traditional petroleum-based products especially for the use as effective ion absorbents, Li-S battery cathode materials, adhesives and controlled release fertilizers, etc. Finally, a few prospects and challenges about the future of these intriguing sulfur-based polymers are raised and discussed.