Renewable (Bis)pyrrolidone Based Monomers as Components for Thermally Curable and Enzymatically Depolymerizable...

Area of Science:

• Polymer Chemistry
• Materials Science
• Organic Synthesis

Background:

• Development of sustainable and renewable thermoset materials is crucial for reducing environmental impact.
• Traditional thermosets often rely on petroleum-based precursors.
• Itaconic acid offers a bio-based platform for novel monomer synthesis.

Purpose of the Study:

• To synthesize novel bis(pyrrolidone) based dicarboxylic acids from itaconic acid.
• To investigate their application in 2-oxazoline resins for fully renewable thermoset materials.
• To analyze the curing kinetics and properties of the resulting thermosets.

Main Methods:

• Synthesis via bulk aza-Michael addition of diamine and itaconic acid.
• Isolation and purification of monomers through recrystallization.
• Characterization using Nuclear Magnetic Resonance (NMR), Gel Permeation Chromatography (GPC), and Fourier-Transform Infrared Spectroscopy (FTIR).
• Curing studies of 2-oxazoline resins with the synthesized dicarboxylic acids.

Main Results:

• Bis(pyrrolidone) based dicarboxylic acids were successfully synthesized from itaconic acid.
• Monomer yield is dependent on diamine spacer length, with even numbers yielding higher amounts.
• These novel dicarboxylic acids significantly enhance curing rates in 2-oxazoline resins compared to aliphatic counterparts.
• Curing rate is influenced by the dicarboxylic acid, while the bis(2-oxazoline) compound affects amide group reactions.
• Resulting thermosets are water-plasticizable, suggesting potential for enzymatic degradation.

Conclusions:

• Novel bis(pyrrolidone) dicarboxylic acids derived from itaconic acid are effective monomers for renewable thermosets.
• The structure of the dicarboxylic acid dictates curing rates in 2-oxazoline systems.
• The developed thermosets offer tunable properties and potential for environmentally friendly degradation pathways.