Mineral Filler Hybridization in Recycled Polyethylene Terephthalate

Area of Science:

• Materials Science and Engineering
• Polymer Science
• Composite Materials

Background:

• Recycled polyethylene terephthalate (RPET) is a sustainable alternative to virgin polymers.
• Mineral fillers can enhance the mechanical and thermal properties of polymer composites.
• Hybrid fillers offer synergistic effects, potentially improving composite performance beyond single fillers.

Purpose of the Study:

• To evaluate the mechanical, thermal, and morphological properties of RPET hybrid mineral-filled composites.
• To investigate the effects of different mineral fillers (wollastonite, mica, talc) and their combinations on RPET properties.
• To assess the dynamic mechanical response of these composites.

Main Methods:

• Preparation of RPET composites with varying contents of single and hybrid mineral fillers (wollastonite, mica, talc) up to 20% by weight.
• Mechanical testing: tensile, compression, and flexural properties.
• Thermal analysis: heat distortion temperature and degree of crystallinity.
• Dynamic mechanical analysis (DMA) at frequencies of 1 Hz, 2 Hz, 5 Hz, and 10 Hz.
• Morphological analysis using scanning electron microscopy (SEM).

Main Results:

• All hybrid mineral-filled RPET composites exhibited enhanced stiffness, strength, and thermal stability compared to unfilled RPET.
• Wollastonite-talc filled RPET composites demonstrated the most favorable results, indicating good filler-matrix compatibility.
• Increased filler content generally led to improved mechanical and thermal properties.
• SEM analysis revealed insights into the fracture surface and morphology, correlating with observed property enhancements.

Conclusions:

• Hybrid mineral filling is an effective strategy to improve the performance of recycled polyethylene terephthalate.
• The combination of wollastonite and talc as fillers in RPET yields superior mechanical and thermal properties.
• These findings support the use of RPET-based hybrid composites in applications requiring enhanced material performance and sustainability.