Development of value‐added polyethylene grades with extended service lifetime: Weathering resistant flame retarded materials for outdoor applications

This chapter presents an overview of current trends in plastic recycling and focuses on specific topics of interest. Firstly, there are presented all methods used for plastic recycling, along with the advantages and disadvantages of each method. Extra attention is paid to chemical recycling and especially, pyrolysis (thermal and catalytic), which is an environmentally friendly method that results in the formation of value-added products. Emphasis is given on three case studies where there are difficulties as regards the recycling of the plastic part: polymeric blends, since the existence of mixed plastic wastes may be challenging for their recycling; plastics originating in multilayer packaging, since the multilayer packaging consists of various materials, including plastics, paper, and metals that may be an obstacle for the recycling of the plastic part; and brominated flame-retarded plastics from waste electric and electronic equipment (WEEE), since in this case safe handling is required in order to avoid environmental contamination and a pretreatment step before recycling may be of paramount importance. These three case studies along with the mentioned difficulties and suggestions in order to overcome them are presented here, with the aim of offering insights for future studies on the management of plastic materials.

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EELS Measurement of the Local Electronic Structure of Copper Atoms Segregated to Aluminum Grain Boundaries

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164179 ◽

1996 ◽

Vol 54 ◽

pp. 342-343

Author(s):

S.J. Splinter ◽

J. Bruley ◽

P.E. Batson ◽

D.A. Smith ◽

R. Rosenberg

Keyword(s):

Electronic Structure ◽

Grain Boundaries ◽

Boundary Segregation ◽

Thin Layers ◽

Nominal Composition ◽

Spatially Resolved ◽

Service Lifetime ◽

Heat Treated ◽

Probe Size ◽

Local Electronic Structure

It has long been known that the addition of Cu to Al interconnects improves the resistance to electromigration failure. It is generally accepted that this improvement is the result of Cu segregation to Al grain boundaries. The exact mechanism by which segregated Cu increases service lifetime is not understood, although it has been suggested that the formation of thin layers of θ-CuA12 (or some metastable substoichiometric precursor, θ’ or θ”) at the boundaries may be necessary. This paper reports measurements of the local electronic structure of Cu atoms segregated to Al grain boundaries using spatially resolved EELS in a UHV STEM. It is shown that segregated Cu exists in a chemical environment similar to that of Cu atoms in bulk θ-phase precipitates.Films of 100 nm thickness and nominal composition Al-2.5wt%Cu were deposited by sputtering from alloy targets onto NaCl substrates. The samples were solution heat treated at 748K for 30 min and aged at 523K for 4 h to promote equilibrium grain boundary segregation. EELS measurements were made using a Gatan 666 PEELS spectrometer interfaced to a VG HB501 STEM operating at 100 keV. The probe size was estimated to be 1 nm FWHM. Grain boundaries with the narrowest projected width were chosen for analysis. EDX measurements of Cu segregation were made using a VG HB603 STEM.

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Sustainable 2,5-furandicarboxylic synthesis by a direct 5-hydroxymethylfurfural fuel cell based on a bifunctional PtNiSx catalyst

Chemical Communications ◽

10.1039/d0cc06087a ◽

2020 ◽

Vol 56 (88) ◽

pp. 13611-13614

Author(s):

Jialu Wang ◽

Xian Zhang ◽

Guozhong Wang ◽

Yunxia Zhang ◽

Haimin Zhang

Keyword(s):

Fuel Cell ◽

Electric Energy ◽

Value Added ◽

Chemical Energy ◽

New Type

A new type of direct 5-hydroxymethylfurfural (HMF) oxidation fuel cell based on a bifunctional PtNiSx/CB catalyst not only transformed chemical energy into electric energy but also converted HMF into value-added 2,5-furandicarboxylic (FDCA).

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