Polyurethane foams (PUFs) are used in a variety of comfort applications or as thermal and acoustic insulation materials. Global production of PUFs is estimated to increase to 12.7 million tons by 2024. For this reason, recycling of PUFs is important from both an economic and environmental point of view. We developed an efficient process for the chemical recycling of PUFs by microwave-assisted acidolysis or aminolysis, resulting in high quality polyether polyols that can be used in further synthesis of flexible or rigid PUFs.
The invention describes a process for microwave-assisted chemical recycling of PUFs to polyether polyols by acidolysis or aminolysis, and the process for purification of the recovered polyols.
The advantages of our chemical recycling method for aliphatic polyamides compared to known methods are the rapid (less than one hour compared to several hours) and efficient degradation of PUFs to polyether polyols and residual PUF hard segments. The recycled polyether polyols show molecular weight characteristics comparable to those of corresponding commercial polyols, while the end- group functionality of the recovered polyol depends on the method used to degrade the PUFs. Depending on the end-group functionality of the recycled polyols, they can be used as partial or full substitute of virgin polyols in the synthesis of flexible PUFs without the need of adjusting the PUF formulation or synthetic conditions.
Fields of use: Recycling, waste management
Technology Readiness Level: TRL3
Intellectual property: Patent pending
Partner sought: R&D collaboration to further develop the technology, licensing or sell of IP rights.
Next steps needed: Testing in an industrial environemnt, scale-up.