Advanced Recycled Polyethylene Terephthalate Aerogels from Plastic Waste for Acoustic and Thermal Insulation Applications

Abstract

This work presents for the first time, a simple, practical and scalable approach to fabricating recycled polyethylene terephthalate (rPET) aerogels for thermal and acoustic insulation applications. The rPET aerogels were successfully developed from recycled PET fibers and polyvinyl alcohol (PVA) and glutaraldehyde (GA) cross-linkers using a freeze-drying process. The effects of various PET fiber concentrations (0.5, 1.0 and 2.0 by wt.%), fiber deniers (3D, 7D and 15D) and fiber lengths (32 mm and 64 mm) on the rPET aerogel structures and multi-properties were comprehensively investigated. The developed rPET aerogels showed a highly porous network structure (98.3–99.5%), ultra-low densities (0.007–0.026 g/cm3), hydrophobicity with water contact angles of 120.7–149.8°, and high elasticity with low compressive Young’s modulus (1.16–2.87 kPa). They exhibited superior thermal insulation capability with low thermal conductivities of 0.035–0.038 W/m.K, which are highly competitive with recycled cellulose and silica-cellulose aerogels and better than mineral wool and polystyrene. The acoustic absorption results were also found to outperform a commercial acoustic foam absorber across a range of frequencies.

Textile Fabrics Containing Recycled Poly(ethylene terephthalate), Oyster Shells, and Silica Aerogels with Superior Heat Insulation, Water Resistance, and Antibacterial Properties

“…Thermal conductivity and thermal diffusivity are important indicators of the insulating properties of textile products. , Table shows that the thermal conductivity and thermal diffusivity of the rPET/ASAG or rPET/ASAG fabrics were lower than those of rPET fabrics. Both factors decreased significantly with increasing SAG and ASAG content from 0.0457 W/(m K)/0.256 mm 2 /s to 0.0356 W/(m K)/0.145 mm 2 /s and 0.0343 W/(m K)/0.138 mm 2 /s for the rPET/SAG and rPET/ASAG textile fabrics, respectively (Table ).…”

Roadmap to sustainable plastic waste management: a focused study on recycling PET for triboelectric nanogenerator production in Singapore and India

“…A PET aerogel fabric made from the electrospun PET nanofibers could confer lightweight property, high porosity (large surface-to-volume ratio), high flexibility, excellent absorption capacity and low thermal conductivity on the aerogel (Thai et al 2019 ). The excellent properties of PET aerogels have led to numerous potential applications, ranging from heat and sound insulations to wastewater treatment (Koh et al 2018 ; Le et al 2019 , 2020 ; Thai et al 2019 ). This focused discussion is on the use of PET aerogels for triboelectric nanogenerator (TENG), a device which is intended for sustainable energy production (see Fig.…”

Recent Progresses in Eco-Friendly Fabrication and Applications of Sustainable Aerogels from Various Waste Materials

“…In 2018, recycled polyethylene terephthalate (rPET) aerogels from plastic bottles were introduced. The aerogel network is formed by hydrogen bonds between rPET fiber and poly(vinyl alcohol) (PVA), and acetal bonds between rPET fiber and glutaraldehyde [ 38 ]. The rPET aerogels show a hydrophobicity with water contact angles of 120.7°–149.8°, and a high elasticity with a low compressive Young’s modulus (1.16–2.87 kPa).…”