Comparison of post-consumer recycling PET bottles production from flakes and regranulate

Mechanical, optical, and thermal properties of cosmetic bottles made from two types of postconsumer waste (PCR) PET were studied: solid-state polycondensation (SSP) regranulate and flakes decontaminated using an infrared cleaning system.The bottles were manufactured using a single-stage injection stretch molding (ISBM) process.The intrinsic viscosity, wall thickness distribution, top load strength, degree of crystallinity, CIELab color parameters, and acetaldehyde (AA) and other volatile organic compounds (VOC) content were determined.The regranulate bottles had higher intrinsic viscosity, and a higher degree of crystallinity.They also exhibited higher top load strength and improved optical and aesthetic quality, due to more effective chain rebuilding and filtration during SSP processing.Bottles made from decontaminated flakes had a more uniform wall thickness distribution, but contained more and larger contaminants.Both materials meet the mechanical requirements for cosmetics packaging, confirming the suitability of 100% PCR PET for applications with high aesthetic requirements.