Enhancing Flame-Retardant Properties of Polyurethane Aerogels Doped with Silica-Based Particles

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Polyurethane (PUR) aerogels are advanced materials with potential applications in thermal insulation and structural components.
• Enhancing the thermal stability and flame retardancy of PUR aerogels is crucial for expanding their use in demanding environments.
• Silica (SiO2) nanoparticles derived from renewable sources offer a sustainable approach to material modification.

Purpose of the Study:

• To synthesize and characterize polyurethane (PUR) aerogels doped with silica (SiO2) particles derived from rice husk.
• To investigate the effects of varying SiO2 content on the physicochemical, thermal, and flame-retardant properties of PUR aerogels.
• To evaluate the potential of these doped aerogels for high-temperature and fire safety applications.

Main Methods:

• Synthesis of SiO2 nanoparticles from rice husk via acid digestion.
• Incorporation of SiO2 nanoparticles into polyurethane (PUR) matrix to form aerogels.
• Characterization of aerogel properties including thermal stability, flame retardancy, and physicochemical characteristics through various analytical techniques.

Main Results:

• Increasing SiO2 content (0.5-3 wt.%) improved the lightness, thermal stability, and flame-retardant properties of PUR aerogels.
• Optimal performance was achieved at a 2 wt.% SiO2 doping level, resulting in up to an eightfold increase in flame retardancy.
• Modification of SiO2 particles with phytic acid did not enhance flame retardancy.

Conclusions:

• Renewable silica (SiO2) nanoparticles effectively enhance the thermal stability and flame retardancy of polyurethane (PUR) aerogels.
• Doped PUR/SiO2 aerogels demonstrate significant potential for applications requiring high-temperature resistance and improved fire safety.
• The synthesis method and SiO2 content are critical factors in optimizing the performance of these advanced composite materials.