Degradable Polyacetals/Ketals from Alternating Ring-Opening Metathesis Polymerization

Area of Science:

• Polymer Chemistry
• Organic Synthesis
• Materials Science

Background:

• Controlled synthesis of degradable polymers is crucial for sustainable materials.
• Existing methods may lack precise control over molecular weight and degradation.
• Alternating ring-opening metathesis polymerization (AROMP) offers a potential route for precise polymer construction.

Purpose of the Study:

• To synthesize degradable polyacetals and polyketals with controlled molecular weights and low dispersities.
• To investigate the use of AROMP for controlled polymerization of cyclopropenes and dioxepins.
• To explore the degradation behavior of the synthesized polymers under acidic conditions.

Main Methods:

• Alternating ring-opening metathesis polymerization (AROMP) of 1,1-disubstituted cyclopropenes and dioxepins.
• Optimization of reaction conditions to achieve high degrees of alternation.
• Characterization of polymer molecular weights, dispersities, and degradation rates.

Main Results:

• Achieved controlled polymerization and high degrees of alternation between nonpropagating cyclopropenes and low-strain dioxepins.
• Synthesized degradable polyacetals and polyketals with controlled molecular weights and low dispersities.
• Demonstrated tunable degradation rates of the polymers in acidic conditions based on acetal/ketal structures.

Conclusions:

• AROMP is an effective strategy for synthesizing degradable polyacetals and polyketals with precise control.
• The developed polymers exhibit tunable degradation, offering potential for controlled release applications.
• This approach allows for the incorporation of diverse functionalities into polymer backbones and side chains.