Performance Enhancement of Polyurethane Acrylate Resin by Urushiol: Rheological and Kinetic Studies

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• Polyurethane acrylic resins are widely used in coatings.
• Developing sustainable and effective cross-linking agents is crucial for material enhancement.
• Urushiol, a natural product, presents potential as a bio-based modifier.

Purpose of the Study:

• To investigate the use of urushiol as a cross-linking agent for commercial wet-cured polyurethane acrylic resin.
• To characterize the modified paint films and evaluate their properties.
• To explore the application of theoretical models for understanding the curing kinetics.

Main Methods:

• Fourier Transform Infrared Spectroscopy (FTIR) for chemical structure analysis.
• Scanning Electron Microscopy (SEM) for surface morphology.
• Thermogravimetric Analysis (TGA) for thermal stability assessment.
• Dynamic Mechanical Analysis (DMA) to study viscoelastic properties.

Main Results:

• Urushiol incorporation significantly increased the cross-linking density of the resin.
• Enhanced film-forming properties, improved mechanical strength, and superior thermal stability were observed.
• Dynamic moduli (G' and G″) followed a power law relationship with gel point frequency, consistent with percolation theory.

Conclusions:

• Urushiol is an effective natural cross-linking agent for polyurethane acrylic resin.
• The modified resin exhibits superior material and thermal properties.
• The study provides a novel approach using autocatalytic models for non-isothermal kinetic studies of urushiol-based polyurethanes.