Unsaturated Polyester Resin Nanocomposites Based on Post-Consumer Polyethylene Terephthalate.

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Materials

Background:

• Recycling polyethylene terephthalate (PET) into valuable materials remains a challenge.
• Developing sustainable alternatives to virgin polymers is crucial for environmental protection.
• Unsaturated polyester resins (UPRs) are versatile polymers with diverse applications.

Purpose of the Study:

• To develop an upcycling method for producing unsaturated polyester resins (UPRs) from recycled PET.
• To synthesize and characterize UPRs using recycled PET as a matrix.
• To investigate the mechanical properties of UPR-based nanocomposites.

Main Methods:

• A three-stage upcycling process: oligoester synthesis, simultaneous glycolysis and interchain exchange with PET, and resin modification.
• Characterization of UPRs using Fourier-transform infrared (FTIR) spectroscopy and gel permeation chromatography (GPC).
• Evaluation of mechanical properties (tensile strength, elongation at break, Young's modulus) of titanium dioxide-reinforced UPR nanocomposites.

Main Results:

• The proposed method successfully produced UPRs from recycled PET.
• 1,2-propylene glycol units were found to significantly enhance UPR properties despite lower reactivity.
• The most promising nanocomposite sample achieved a tensile strength of 112.62 MPa, elongation at break of 157.94%, and Young's modulus of 29.95 MPa.

Conclusions:

• The developed upcycling method effectively transforms recycled PET into UPR nanocomposites with high mechanical performance.
• This approach offers a viable route for creating valuable products from plastic waste, promoting a circular economy.
• The findings demonstrate the potential of using recycled PET in advanced material applications.