Towards fully biobased polymers formulations.

International audienc

Tire and road wear particles in the environment: a morphological signature.

International audienc

Characterization of polydimethylsiloxane rubber upon photochemical, thermal, salf-fog ageings and exposure to acid vapours

International audienc

Impacts environnementaux des particules d’usure de pneumatiques.

International audienc

Time-varying microplastic contributions of a large urban and industrial area to river sediments

International audienceThe quantification of microplastic (MP) pollution in rivers is often constrained by a lack of historical data on a multi-decadal scale, which hinders the evaluation of public policies. In this study, MP contents and trends were analyzed in dated sediment cores sampled upstream and downstream of a large metropolis, in environmental deposits that exhibited consistent sedimentation patterns from the 1980s to 2021. After a thorough sedimen- tological analysis, MPs were quantified in samples by micro Fourier Transform InfraRed spectroscopy (μFTIR imaging) and a density separation and organic matter digestion procedure. Microplastics recorded in the up- stream core are relatively ubiquitous all along the dated sequence. The results also confirmed a sever increase of microplastics levels in the downstream core, by one order of magnitude, and an increase of polymer types. Polypropylene, polyethylene, and polystyrene represent ubiquitous contamination and were predominant at the two stations, whereas polyvinyl chloride and polytetrafluoroethylene were suspected to be abundant at the downstream station, but were not detected at the upstream station. Their presence could be linked to local contamination from specific industrial sources that manufactured and utilized these polymers. Surprisingly, in the downstream station sediment has recorded a relative improvement in polymers associated with industrial sources since the 2000s and, to a lesser extent, for ubiquitous ones since the 2010s. This trend of mitigation diverges from that of global assessments, that assume uncontrolled MP pollution, and suggest that European Union wastewater policy and regulation on industrial discharges have positively influenced water quality, and certainly also on MPs. However, the accumulation of microplastics remains high in recent deposits and raises the emerging concern of the long-term management of these reservoirs

The life-story of plastic butter tubs.

International audienc

Degradation pathway of polypropylene based post-consumer plastic in natural riverbank environment.

International audienc

Caracterização de tubo e adesivo utilizados em tubulações de plástico reforçado com fibras de vidro aplicados em plataformas marítimas Characterization of pipes and adhesives of glassfiber reinforced plastics used in offshore platforms

Na indústria de exploração e produção de petróleo, principalmente no setor offshore, os plásticos reforçados por fibras de vidro (PRFV) têm apresentado grande destaque. Isso se deve à intrínseca capacidade destes de resistir à corrosão em ambientes salinos, bem como serem materiais que apresentam elevada resistência mecânica específica. O presente trabalho buscou caracterizar tubo e adesivo utilizados em plataformas marítimas. Para tanto, as técnicas utilizadas foram: espectroscopia na região do infravermelho com transformada de Fourier (FTIR), análise termogravimétrica (TGA), análise termodinâmico-mecânica (DMTA) e temperatura de amolecimento de Vicat. Amostras do tubo de PRFV e dos componentes do adesivo (denominados de A e B) foram estudadas individualmente. Além disso, foram confeccionadas misturas, em massa, nas seguintes proporções: 40%A-60%B, 50%A-50%B e 60%A-40%B. Foi possível determinar a composição e a estrutura química dos materiais, além do comportamento mecânico à degradação térmica. Foi verificado que adesivo e tubo apresentaram desempenho satisfatório à temperatura ambiente quanto à degradação e à rigidez. Por outro lado, quando submetido ao calor, principalmente os adesivos, apresentaram queda brusca de desempenho.<br>Glassfiber reinforced plastics (GFRP) have been applied in the offshore industry owing to their high resistance to corrosion and high specific mechanical strength. The present work aimed at characterizing pipes and adhesives used in offshore platforms in order to evaluate the thermo-mechanical performance of these materials. The techniques used were: Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis (TGA), dynamic mechanical thermal analysis (DMTA) and Vicat softening temperature. Specimens of GFRP pipe and adhesive components (referred to as A and B) were evaluated individually. The adhesive samples were made in the following ratios (% weight): 40%A-60%B, 50%A-50%B and 60%A-40%B. The results showed it to be possible to determinate the composition and structure of the materials, as well as the mechanical behavior regarding thermal degradation. The adhesive and pipe exhibited satisfactory performance at room temperature, with regard to degradation and stiffness. Nevertheless, at higher temperatures, both materials, especially the adhesives, presented abrupt strength reduction