Thiol-Acrylate polyHIPEs via Facile Layer-by-Layer Photopolymerization.

Area of Science:

• Polymer Chemistry
• Materials Science
• Additive Manufacturing

Background:

• High internal phase emulsions (HIPEs) are versatile platforms for creating porous materials.
• Additive manufacturing (AM) offers customizable fabrication of complex structures.
• Developing solvent-free, efficient photopolymerization systems is crucial for sustainable AM.

Purpose of the Study:

• To develop a highly reactive thiol-ene HIPE formulation for light-driven additive manufacturing.
• To achieve rapid polymerization with low photoinitiator concentrations.
• To create customizable, highly porous poly(high internal phase emulsion) materials without harmful solvents.

Main Methods:

• Formulation of a thiol-ene high internal phase emulsion using 1,6-hexanediol diacrylate and tris 2-(3-mercaptopropionyloxy)ethyl isocyanurate.
• Utilizing light-driven polymerization for additive manufacturing.
• Incorporating a thiol as a chain-transfer agent to mitigate brittleness and oxygen inhibition.

Main Results:

• Successful development of a highly reactive thiol-ene HIPE system.
• Achieved short irradiation times and required low photoinitiator amounts.
• Produced highly porous, customizable poly(HIPEs) with layer thickness <50 μm and average pore size <5 μm.
• Demonstrated a solvent-free formulation suitable for scale-up and industrial applications.

Conclusions:

• The developed thiol-ene HIPE is an effective system for light-driven additive manufacturing.
• The formulation enables the production of advanced porous materials with tunable properties.
• The solvent-free approach promotes feasibility for industrial adoption and sustainable manufacturing.