Organophosphorus Stabilisers of Polymers: Efficiency and the Mechanisms of Action

Abstract

Because of their unique structure, it has been proposed that carbon nanotube ropes may well provide an ideal container for the storage of molecular hydrogen. Indeed, there has been some experimental evidence of enhanced hydrogen uptake in doped Li and other alkali metal systems (Chen et al 1999 Science 285 91). We have therefore addressed this issue of hydrogen storage in Li-doped graphite and carbon nanotube systems theoretically with ab initio simulations. Our results find no evidence for such enhanced storage, based on the induced structural changes. In addition, we have also investigated the diffusion barriers for hydrogen to enter into nanotube interiors, both in the presence and absence of topological defects. Even if nanotube interiors are made accessible, the hydrogen uptake remains modest, i.e., less than 3.5 wt%. Mechanically or chemically processing nanotubes is therefore not likely to lead to greatly increased hydrogen storage. Even with its limitation, because of the use of the LDA and GGA approaches, the current investigation must be regarded as a means in the search for proper media that can successfully enhance hydrogen storage.

Study of the Nature of the Influence of some Oligophosphonates on the Rheological Properties of High-Density Polyethylene

“…The nature of the effect of oligophosphonates on the melt flow rate (MFR) of high-density polyethylene depending on the concentration of oligomers and the molecular weight distribution of the MWD polymer was assessed by the method of multiple high-temperature extrusion (n = 1-5) of the samples. Numerous works have been devoted to research methods for polymers, including polyolefins [2][3][4][5][6][7][8].…”

Avaliação Da Degradação Térmica E Oxidativa De Um Fosfato Éster E De Um Óleo Naftênico

“…Outra característica bastante importante dos organofosforados é o fato de serem estáveis em condições extremas, bem como se apresentarem no estado líquido, facilitando a miscibilidade quando adicionados a formulações lubrificantes (Kirpichnikov et al, 1983).…”

Phosphorus cardanol: chemical characterization and thermal stability

“…They have potent antioxidant activity in several industrial areas such as: fuels and biofuels; tribology; polymers [5,6]; rubbers [7][8][9][10] and can be used in the biological industry too as antibacterial, anti-fungal and anti-tumor [11,12].…”