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Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Marine & Wildlife Remediation Sign in to save

Degradation and fragmentation behavior of polypropylene and polystyrene in water.

Research Square (Research Square) 2022 7 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Hisayuki Nakatani, Yuina Ohshima, Taishi Uchiyama, Motokucho Suguru

Summary

Polypropylene and polystyrene retrieved from beaches were compared in their surface texture and degradation behavior when exposed to highly reactive sulfate radicals in water. Polypropylene showed more surface roughening than polystyrene, and both plastics produced degradation products at different rates. The study provides insight into how common plastics break down in aquatic environments into microplastic fragments.

Polymers
Study Type Environmental

Abstract A polystyrene (PS) retrieved from the beach exhibited no change in surface texture. In contrast to it, a retrieved polypropylene (PP) had a rumpled surface texture. Highly reactive sulfate radical generated by K 2 S 2 O 8 was employed as degradation initiator of PP and PS, and their degradation behavior was studied in water. The PS carbonyl index value gradually went up down, and its molecular weight (MW) curve discontinuously shifted to a lower MW with the increase of the degradation time unlike the PP. It was found that PP microplastic production rate was approximately three time higher than PS from weight ratio dependence on degradation time. The higher microplastic production rate of PP arose from its crystallizability. The voids were produced by change in specific volume occurring by chemi-crystallization and then provoked the cracks leading to quick fragmentation. The SEM photographs suggested that the PP microplastic size facilely reached nm order by the cracking around lamella.

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