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Metalworking Fluids
Published in Leslie R. Rudnick, Synthetics, Mineral Oils, and Bio-Based Lubricants, 2020
William L. Brown, Richard G. Butler
The second type of synthetic lubricants that are finding use in semichemical fluids as a chlorine replacement are complex polymeric synthetic esters. These complex polymeric esters (CPE) are both soluble in mineral oil and emulsifiable in water. In Figure 46.12, the pentaerythritol backbone of CPE is illustrated. Up to four different species may be reacted at each terminal hydroxyl group. Many different possibilities for forming different CPE are possible. Three major types are commercially available; complex polymeric vegetable esters (CPVE), complex polymeric sulfurized esters (CPSE) and another form SSE based upon a pentaerythritol center. Structure of pentaerythritol that is used as a base for forming complex polymeric ester synthetic lubricants.
Synthesis of Reactants and Intermediates for Polymers
Published in Charles E. Carraher, Carraher's Polymer Chemistry, 2017
Pentaerythritol, used in the production of alkyds, is produced by a crossed Cannizzaro reaction of the aldol condensation product of formaldehyde and acetaldehyde. The by-product formate salt is a major source of formic acid.
A comprehensive review of sustainable approaches for synthetic lubricant components
Published in Green Chemistry Letters and Reviews, 2023
Jessica Pichler, Rosa Maria Eder, Charlotte Besser, Lucia Pisarova, Nicole Dörr, Martina Marchetti-Deschmann, Marcella Frauscher
One major aspect when it comes to stability is the crucial knowledge of structure-stability relationships (149). With this knowledge, nearly tailor-made lubricant components for each application can be synthesized. Based on targeted synthesis via long-chain alcohols and acids, the resulting completely saturated synthetic esters show high thermo-oxidative and hydrolytic stability as well as more stable ageing characteristics (145). For example, feedstocks include C6–C13 alcohols (i.e. n-hexanol, n-heptanol, isonal, and decanol), C5–C18 mono acids (i.e. valeric, heptanoic, pergalonic, and oleic acid) with neopentyl polyols, such as pentaerythritol (PE), polyol esters, diacids (i.e. adipic acid, azelaic, sebacic, and dodecanedioic), and various dimer acids (145).
Three-dimensional printing of blue-colored zirconia accessories using digital light processing-based stereolithography
Published in Journal of Asian Ceramic Societies, 2021
Yanhui Li, Shengliang Wang, Minglang Wang, Xinyue Zhang, Binwen Lu, Yueliang Wang, Dongdong Dong, Fupo He, Wei Liu, Shanghua Wu
A ball-milling approach was then applied to prepare a uniform photosensitive resin, including ethoxylated pentaerythritol tetraacrylate (PPTTA, Aladdin), 1,6-hexanediol diacrylate (HDDA, Aladdin), di-functional aliphatic urethane acrylate (U600, Aladdin), 1-octanol (octanol, Aladdin), and some other additives. In the next step, blue-colored photosensitive suspensions were prepared. This step involved the mixing of the above resin with the blue-colored 3Y-TZP powder using the ball-milling method for 2 h, and then the optimal photoinitiator, 1 wt% of photosensitive resin, was added to the suspensions. All the suspensions had the same solid content of 28 vol%, which is sensitive to cure properties. Preparation and characterization of the single layer and accessories
Remediation of 2,4,6-trinitrotoluene Persistent in the Environment – A review
Published in Soil and Sediment Contamination: An International Journal, 2020
Synthetic surfactants such as Triton X-100 and Tween 80 can also be used for the same remediation purposes. Boopathy (2002) investigated TNT degradation with the surfactant Tween 80 which served as an additional carbon substrate for the microorganisms. The study highlights the potential of Tween 80 in desorbing TNT from soil and makes it bioavailable to the microbes. It was observed that TNT and its metabolite, 4-amino-2, 6-dinitrotoluene were degraded faster in a period of 35 days. However, the addition of Tween 80 alone did not result in complete TNT removal. Molasses, the carbon source, was added to improve the remediation. Sadani et al. (2016) demonstrated explosive biotransformation in soils using rhamnolipid. Biosurfactant rhamnolipids improved the solubility of the explosive Pentaerythritol Tetranitrate (PETN), enhanced dispersion in aqueous solution and promoted homogeneous distribution in soil. Out of the many explosive‐transforming cultures containing Proteobacteria of the genera Achromobacter, Stenotrophomonas, Pseudomonas, Sphingobium, Raoultella, Rhizobium, and Methylopila, Achromobacter spanius S17 and Pseudomonas veronii S94 possess high TNT transformation rates and act as biosurfactant producers especially when an additional carbon source is generally added. Recent study by Amin et al. (2017)demonstrated concomitant removal of TNT and PETN from the soil in aerobic conditions with the aid of rhamnolipid biosurfactant. Sadani et al. (2016) showed increased solubility of TNT and enhanced biodegradation rates with rhamnolipids.