0
Article Tier 2 Remediation Sign in to save

Study on the Mechanism of Molecular Weight Reduction of Polyethylene Based on Fe-Montmorillonite and Its Potential Application

Polymers 2023 6 citations

AI summary Read the abstract

Researchers investigated the mechanism by which Fe-montmorillonite accelerates polyethylene molecular weight reduction during photodegradation, finding that iron ions catalyze chain scission before oxidative degradation, offering potential for breaking down PE plastic waste.

Polymers

The reactions occurring in the oxidative degradation phase during the photo-oxidative degradation of polyethylene (PE) are the factors leading to molecular weight reduction. However, the mechanism of molecular weight reduction before oxidative degradation has not been clarified. The present study aims to investigate the photodegradation of PE/Fe-montmorillonite (Fe-MMT) films, especially molecular weight change. The results show the rate of photo-oxidative degradation of each PE/Fe-MMT film is much faster than that of the pure linear low-density polyethylene (LLDPE) film. A decrease in the molecular weight of polyethylene was also found in the photodegradation phase. Based on this, it was found that the transfer and coupling of primary alkyl radicals originating from photoinitiation lead to a decrease in the molecular weight of polyethylene, and the kinetic results validate this new mechanism well. This new mechanism is an improvement on the existing mechanism of molecular weight reduction during the photo-oxidative degradation of PE. In addition, Fe-MMT can greatly accelerate the reduction of PE molecular weight into small oxygen-containing molecules as well as induce cracks on the surface of polyethylene films, all of which can accelerate the biodegradation process of polyethylene microplastics. The excellent photodegradation properties of PE/Fe-MMT films will be useful in the design of more environmentally friendly degradable polymers.

More Papers Like This

Article Tier 2

Insight into the Photodegradation of Microplastics Boosted by Iron (Hydr)oxides

AI summary Read the abstract

Iron (hydr)oxide minerals goethite and hematite were found to significantly accelerate the photodegradation of polyethylene and polypropylene microplastics under simulated sunlight, with goethite showing greater effect due to higher hydroxyl radical production via a light-driven Fenton reaction. The study reveals a previously overlooked natural mechanism by which common soil minerals can influence the environmental fate of microplastics.

Article Tier 2

Peculiarity of the Mechanism of Early Stages of Photo-Oxidative Degradation of Linear Low-Density Polyethylene Films in the Presence of Ferric Stearate

AI summary Read the abstract

This study investigated how ferric stearate (an iron-based additive used in oxo-degradable plastics) accelerates the early stages of polyethylene photo-oxidation, finding that it acts not merely as a catalyst but actively generates radicals that fragment the polymer chain from the outset. While framed as a materials science study, the findings are relevant to the microplastics debate: oxo-degradable plastics marketed as environmentally friendly may in fact fragment more rapidly into persistent microplastic particles rather than fully mineralizing.

Article

Manganese oxide-mediated inhibition of microplastic photodegradation: insight into the photoreduction mechanism

AI summary

Researchers found that manganese oxides significantly inhibit photodegradation of polystyrene and PVC microplastics by scavenging reactive oxygen species and forming light-shielding complexes, reducing breakdown rates by nearly 58%, challenging the view that minerals accelerate microplastic degradation.

Article

Enhanced photodegradation of polyethylene microplastics via tea polyphenol-hematite complex: Critical role of a light-driven Fenton-like cascade initiated by ligand-to-metal charge transfer

AI summary

Researchers created a composite photocatalytic material by coupling tea polyphenols with hematite iron oxide, which under visible light triggers a self-regenerating Fenton-like reaction that continuously produces hydroxyl radicals, achieving highly efficient degradation of polyethylene microplastics and offering a sustainable, solar-driven remediation strategy using widely available natural materials.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper