Ethynylsulfone-Based Phenol-Yne Click Polymerization Toward Multiple Stimulus-Responsive...

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Synthesis

Background:

• Development of novel polymerization techniques for advanced materials.
• Need for polymers with tunable stereochemistry and stimulus-responsive properties.
• Exploration of metal-free click chemistry for sustainable synthesis.

Purpose of the Study:

• To report a metal-free ethynylsulfone-based phenol-yne click polymerization for synthesizing stereoregulated poly(β-aryloxylvinylsulfone)s (PAVSs).
• To investigate the precise control over polymer stereochemistry (Z/E configuration) and its impact on material properties.
• To develop new stimulus-induced transformations for polymer degradation, conversion, and functionalization.

Main Methods:

• Metal-free ethynylsulfone-based phenol-yne click polymerization.
• Modulation of stereochemistry using catalysts, monomer concentration, and solvents.
• Catalyst-free amine exchange reaction for polymer degradation and conversion.
• Alkene bond cleavage via diamine treatment.
• Photoinduced rearrangement for fluorescence enhancement.

Main Results:

• Efficient synthesis of high-molecular-weight PAVSs with precisely controlled Z/E stereochemistry.
• Distinct thermal and mechanical properties observed for Z- and E-enriched PAVSs.
• Successful demonstration of catalyst-free polymer degradation and polymer-to-polymer conversion.
• Novel C═C bond cleavage reaction achieved using simple diamine treatment.
• Photoinduced rearrangement leading to significant fluorescence enhancement upon UV irradiation.

Conclusions:

• Stereoregulated PAVSs synthesized via metal-free click polymerization offer tunable properties and multiple stimulus-responsive transformations.
• The developed transformations, including degradation, conversion, and photoinduced reactions, expand the utility of PAVSs.
• PAVSs exhibit potential for applications in secure information encoding and encrypted communication due to their photochemical behavior.