Fabrication of Polycaprolactone-Based Polyurethanes with Enhanced Thermal Stability

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Polyurethanes (PU) are versatile polymers with applications limited by their thermal stability.
• Improving the thermal performance of PU is crucial for expanding their use in demanding environments.
• Titanium dioxide nanoparticles (TiO2 NPs) are explored as additives to enhance polymer properties.

Purpose of the Study:

• To investigate the effect of incorporating unmodified and surface-modified TiO2 nanoparticles into polyurethanes.
• To evaluate the impact of TiO2 nanoparticle dispersion on the thermal stability and degradation behavior of PU composites.
• To determine the role of surface modification in enhancing the compatibility and performance of TiO2 NPs within the PU matrix.

Main Methods:

• Synthesis and characterization of PU composites containing varying amounts of unmodified and lauryl gallate-modified TiO2 nanoparticles.
• Microscopy (SEM) for dispersion analysis.
• Swelling tests and mechanical testing for physical property evaluation.
• Thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) for thermal stability assessment.
• Application of iso-conversional model-free methods to analyze thermal degradation kinetics.

Main Results:

• Incorporation of TiO2 nanoparticles significantly improved the thermal stability of polyurethanes.
• Surface modification of TiO2 NPs with lauryl gallate led to better dispersion and a more pronounced enhancement in thermal stability.
• Analysis indicated that modified TiO2 NPs preferentially dispersed in the soft segments of the PU, delaying the degradation of polycaprolactone (PCL) and enhancing overall PU thermal performance.
• Kinetic analysis confirmed the positive influence of TiO2 NPs on the thermal stability and aging resistance of PU.

Conclusions:

• TiO2 nanoparticles are effective in enhancing the thermal stability of polyurethanes.
• Surface modification of TiO2 NPs is key to achieving optimal dispersion and maximizing thermal performance improvements.
• The study demonstrates a viable strategy for developing thermally robust polyurethane materials for advanced applications.