CO₂-Blown Nonisocyanate Polyurethane Foams

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Chemistry

Background:

• Traditional polyurethane (PU) foams rely on toxic isocyanates derived from petrochemicals and phosgene.
• Nonisocyanate polyurethanes (NIPUs) offer a safer alternative, but their foaming process, especially in situ CO2 generation, remains challenging.
• Existing methods struggle to replicate the foaming efficiency seen in traditional PU production.

Purpose of the Study:

• To develop a novel synthesis route for NIPU foams.
• To utilize amine-CO2 adducts as both foaming agents and comonomers.
• To investigate the CO2 adsorption-desorption properties of these adducts for controlled foaming.

Main Methods:

• Synthesis of amine-CO2 adducts.
• Characterization of CO2 adsorption-desorption behavior under varying conditions.
• Aminolysis of amine-CO2 adducts with cyclic carbonate.
• Foaming of NIPU using the prepared adducts at controlled temperatures and times.

Main Results:

• Amine-CO2 adducts demonstrated up to 87% CO2 desorption at 60 °C after aminolysis.
• The synthesized NIPU foams achieved low densities ranging from 0.203 to 0.239 g·cm-3.
• Successful foaming was achieved by heating the adducts at 50-60 °C for 24-48 hours.

Conclusions:

• Successfully synthesized NIPU foams using amine-CO2 adducts as a source of in situ CO2.
• The developed method provides a viable pathway for producing low-density, potentially eco-friendly NIPU foams.
• This approach overcomes previous limitations in NIPU foam synthesis and foaming agent development.