Recyclable thermoplastic silicone elastomers from non-carbon heteroatomic polymer backbones

Area of Science:

• Polymer Chemistry
• Materials Science
• Sustainable Chemistry

Background:

• Traditional silicone materials rely on robust Si-O-Si backbones, necessitating chemical crosslinking for elastomeric properties.
• Existing silicones resist depolymerization, posing challenges for recycling and end-of-life management.

Purpose of the Study:

• To develop a novel silicone elastomer with a recyclable backbone structure.
• To achieve on-demand polymerization-depolymerization cycles for sustainable material applications.

Main Methods:

• A modular synthesis was employed to create polymers with periodic Si-O-Te-O linkages (PTeSiO).
• A one-pot, room-temperature aqueous copolymerization route was utilized.
• Redox-labile tellurium-oxygen (Te-O) motifs were incorporated for backbone scission.

Main Results:

• High-molecular-weight, transparent elastomers with controlled backbone composition and side-chain architecture were synthesized.
• Chemoselective backbone scission was achieved under mild reductive conditions, enabling depolymerization.
• Efficient monomer recovery and on-demand polymerization-depolymerization cycles were demonstrated.
• The resulting elastomers exhibited elasticity, thermoplastic processability, and tunable mechanical properties.

Conclusions:

• The developed PTeSiO elastomers offer a sustainable and recyclable alternative to conventional silicones.
• The modular synthesis strategy provides a general approach for designing non-carbon heteroatomic backbone polymers.
• This work advances the design principles for creating environmentally friendly and recyclable advanced materials.