Compatibilization of recycled poly(ethylene terephthalate) and polypropylene blends: Effect of compatibilization on blend toughness, dispersion of minor phase, and thermal stability

Abstract

Blending of recycled polyethylene terephthalate (RPET) from waste bottles with polypropylene (PP) was performed in an attempt to enhance the processability of RPET. The idea of blending RPET with PP sprouted from the intention of recycling PET bottles together with their PP‐based caps. Therefore, preliminary blending of RPET with neat PP (RPET/PP) was performed at various PP and compatibilizer contents. Morphological analyses on the extruded pellets of uncompatibilized blends indicate that the PP particle size and state of dispersion at skin and core regions were vastly different. The particles at the skin were at least 10 times smaller than that at the core although the size distribution was very wide. With the incorporation of just 5 phr of compatibilizer, the particles at the core region became significantly smaller and appeared to emulate that of the skin region. Furthermore, the overall homogeneity of the blends was vastly improved irrespective of PP content in the blend. The reduction in particle size and improved homogeneity inherently reduced stress concentration points and enhanced the mechanical performance of the blends. More importantly, the incorporation of PP into RPET significantly increased the degradation temperature of the blends, provided the dispersion of PP phase in RPET was excellent. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The investigation of alumina nanoparticles’ effects on the mechanical and thermal properties of HDPE/rPET/MAPE blends

“…Incompatibility between the rPET and polyolefin leads to gross phase separation and poor mechanical properties of the blend [10]. For this reason, compatibilizers such as maleic anhydride polyethylene (MAPE) and maleic anhydride polypropylene (MAPP) are used to improve the compatibility between rPET and polyolefin [11,12].…”

Effects of poly(butylene adipate‐co‐terephthalate) and ultrafined wollastonite on the physical properties and crystallization of recycled poly(ethylene terephthalate)

“…Several approaches have been performed to reduce these physical characteristic problems of rPET, such as the blending of rPET with either biodegradable or non‐biodegradable polymers, such as poly(butylene adipate‐ co ‐terephthalate) (PBAT), polypropylene (PP), ethylene octene copolymer, polycarbonate, and acrylonitrile butadiene styrene terpolymer . Srithep et al reported an increase in the toughness and molecular weight of rPET by the addition of PBAT and chain extender, respectively, and so the mechanical properties and moldability of the rPET were improved .…”

“…Srithep et al reported an increase in the toughness and molecular weight of rPET by the addition of PBAT and chain extender, respectively, and so the mechanical properties and moldability of the rPET were improved . Inoya et al also added PP to rPET to improve the processability, mechanical performance, and degradation temperature of the rPET . Moreover, some inorganic fillers, such as silicon nitride , glass fibers , and nanoclay , have also been used to improve the physical properties of rPET.…”

Rheological, Morphological and Mechanical Characterization of Recycled Poly (Ethylene Terephthalate) Blends and Composites

“…Thus, polymer mixtures usually need a compatibilizer to improve the interfacial adhesion, reduce surface tension and promote morphological stability of the blend 2,3 . Poly (ethylene terephthalate) (PET) is recognized as one of the most versatile engineering plastics; it is mainly used in soft drink bottles and textile industry, being one of the most disposed packing materials 4 . The increasing economic and environmental value of the PET recycling industry has caused interest worldwide.…”