Mechanism of degradation induced embrittlement in polyethylene

Fayolle, Bruno; Colin, Xavier; Audouin, L.; Verdú, J.

doi:10.1016/j.polymdegradstab.2006.11.012

Cited by 136 publications

(112 citation statements)

References 44 publications

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“…The films prepared with PEGd,lPLA and PEG-PLGA multiblock copolymers became brittle to touch with increasing radiation dose. The embrittlement process, which can be found in irradiated films, could be attributed to their degradation as result of gammaradiation treatment (17,18). PLA and PLGA films maintain their texture after irradiation at all doses tested.…”

Section: Effects Of Irradiation Dosesmentioning

confidence: 93%

γ-Irradiation of PEGd,lPLA and PEG-PLGA Multiblock Copolymers: I. Effect of Irradiation Doses

et al. 2008

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Abstract. To evaluate the effects of different gamma irradiation doses on PEGd,lPLA and PEG-PLGA multiblock copolymers. The behaviour of the multiblock copolymers to irradiation was compared to that of PLA, PLGA polymers. PEGd,lPLA, PEG-PLGA, PLA and PLGA polymers were irradiated by using a 60 Co irradiation source at 5, 15, 25 and 50 kGy total dose. Characterization was performed on all samples before and after irradiation, by nuclear magnetic resonance (NMR), infrared absorption spectrophotometry (FTIR) and gel permeation chromatography (GPC). The effect of gamma irradiation on polymer stability was also evaluated. Results of NMR and FTIR suggest an increase in -OH and -COOH groups, attributed to scission reactions induced by irradiation treatment. Data of GPC analysis showed that the weight average molecular weight (Mw) of polymer samples decreased with increasing irradiation dose. The extent of Mw degradation expressed as percentage of Mw reduction was more prominent for polymers with high molecular weight as PEGd,lPLA and PLA. The dominant effect of gamma-irradiation on both polymer samples was chain scission. The multiblock copolymer PEGd,lPLA presented higher sensitivity to irradiation treatment with respect to PLA, likely due to the presence of PEG in the matrix. The effect of gamma irradiation continues over a much longer period of time after gamma irradiation has been performed. It is suggested that the material reacts with oxygen to form peroxyl free radicals, which may further undergo degradation reactions during storage after irradiation.

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Section: Effects Of Irradiation Dosesmentioning

confidence: 93%

γ-Irradiation of PEGd,lPLA and PEG-PLGA Multiblock Copolymers: I. Effect of Irradiation Doses

et al. 2008

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“…[50] Random chain scission (in the main chain) leads to a reduction of molecular weight and hence the deterioration of mechanical stability, including the formation of cracks on the surface and finally the embrittlement of the surface. [51] The latter may be increased by UV-induced crosslinking on the surface, also as the resulting increased density on the surface leads to mechanical tension with unaffected lower-density material deeper below the surface. The deterioration of the surface's integrity allows deeper-situated portions of extractable ions to become accessible to the extraction process.…”

Section: Colour Measurementsmentioning

confidence: 99%

Contaminant release from aged microplastic

et al. 2017

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Environmental context. Increasing global plastic production adds plastic debris to the environment. We show that potentially harmful additives present in plastic particles are released to water at an increased rate when material properties change by aging due to exposure to high temperature and especially to UV radiation. For risk assessment of such plastic additives, more information on their degradation products and their toxicity is needed.Abstract. Recycled plastic granules of high-density polyethylene, polyvinyl chloride and polystyrene the size of microplastics were exposed to artificial aging conditions (2000 h; photooxidative and thermo-oxidative) to simulate their fate outdoors. Their potential to leach into water during the aging process was investigated using column percolation tests. Aging-related changes on the surface of the material were characterised by IR measurements indicating oxidation reactions with the formation of new adsorption bands (C=O, C-O and OH), especially in the case of photooxidative aging. These findings were confirmed by the identification of leachable organic compounds. Leaching of total organic carbon, Cl, Ca, Cu and Zn is clearly affected by changes due to aging, and their release is increased after photooxidative aging. In general, exposure to photooxidative conditions shows a greater influence on aging and thus on leaching and seems to be the more important mechanism for the aging of microplastic in the environment. Comparison with the total content of inorganic species revealed that, for most elements, less than 3% of the total content is released after 2000 h of photooxidative aging.

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“…Organometallic catalysts were developed to produce PE with well-defined structures (average molecular mass, crystallization degree, etc …) [1,2]. Oxidation mechanisms [3], kinetics [4] and the subsequent loss of ductility, often so called embrittlement (even if this term is rather linked to the loss of toughness instead of ultimate elongation) [5] are well documented in literature together with the detrimental role of metallic polymerization catalysts on oxidative stability [6].…”

Section: Introductionmentioning

confidence: 99%