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Synthetic Polyphosphates Related to Nucleic and Teichoic Acids
Published in Stanislaw Penczek, H. R. Kricheldorf, A. Le Borgne, N. Spassky, T. Uryu, P. Klosinski, Models of Biopolymers by Ring-Opening Polymerization, 2018
Stanislaw Penczek, Pawel Klosinski
Alkylene alkyl phosphates, i.e., cyclic triesters of phosphoric acid, can be prepared by various methods, but the phosphorylation with phosphorus oxychioride 44 or O-alkyl phosphorodichloridate 47 are mainly used. The required compounds are obtained in the sequence of two reactions using 44 (Equation 9) or in one step synthesis, starting from the latter agent (Equation 10).
Neutral Phosphate Esters
Published in Leslie R. Rudnick, Synthetics, Mineral Oils, and Bio-Based Lubricants, 2020
W. David Phillips, Douglas C. Placek, Michael P. Marino
Alkyl phosphates are also used as solvents in a variety of applications outside the oil industry, for example, in the extraction of uranium ore, in the production of phosphoric acid, and in surface coatings.
Hydrophobic chemical treatment of aggregate surfaces to re-engineer the mineral/bitumen interface and improve bitumen adhesion
Published in Road Materials and Pavement Design, 2021
Stephen Bagshaw, Tim Kemmitt, Sam Brooke, Mark Waterland, Larry Fertel
Alkyl phosphonates and alkyl phosphates are indicated as being toxic and irritants under exposure to vapour or via ingestion (MSDS 2958-09-0). This is typical and all normal precautions in handling chemicals would need to be taken. As indicated in an earlier section, this system would not be applied via solvent evaporation as was performed in the laboratory. More likely it would be applied via an aqueous emulsion spray-coat or dip-coat system, which would reduce hazards significantly. The production of phosphate-rich dust during aggregate handling could be a problem that would require mitigation strategies and investigation. The amount of alkyl phosphonate/phosphate applied to the aggregate is very small, in the order of mono-molecular layer coverage from approximately 50 ppm solution and is therefore significantly less than the amine type products. The amount of compound that might be released into the environment over time will need to be understood, but for any given unit area of chipseal, the amount of compound present will be vanishingly small. Furthermore, alkyl-phosphonates/phosphates are poorly water soluble so that molecules that are released from a chip surface, could possibly end up being absorbed into the surrounding bitumen. This should be the subject of future investigation.