Dynamic Circular Sulfur-Rich Polymer Glasses From Elemental Sulfur.

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Chemistry

Background:

• Elemental sulfur (S₈), a petroleum byproduct, offers potential for sustainable polymer synthesis.
• Inverse vulcanization (IV) converts S₈ into sulfur-rich plastics, but scalable manufacturing is hindered by poor understanding of molten sulfur chemistry.

Purpose of the Study:

• To identify critical parameters for scalable inverse vulcanization manufacturing.
• To develop novel sulfur-rich polymer glasses (IVG) for optical applications.
• To investigate the properties and processability of IVG materials.

Main Methods:

• Investigated molten sulfur homogeneity as a key parameter in inverse vulcanization.
• Utilized ultra-high-purity sulfur melts to establish manufacturing boundary conditions.
• Fabricated large-scale inverse vulcanized glass (IVG) precision optics.

Main Results:

• Identified molten sulfur homogeneity as critical for producing 70-80 wt.% sulfur-rich polymer glasses (IVG).
• Enabled fabrication of large IVG precision optics with high refractive index and broadband visible-infrared transparency.
• Demonstrated that IVG possesses covalent adaptable networks and can be melt-reprocessed.

Conclusions:

• Molten sulfur homogeneity is a critical factor for scalable inverse vulcanization.
• Inverse vulcanized glass (IVG) is a viable, affordable optical material with tunable properties and recyclability.
• IVG offers a sustainable alternative to traditional inorganic optical materials.