Dispersants interaction with antioxidants

Partial silylation of the highly disperse silica surface enhances the adsorption of vitamin E from ethanol solution, and provides the ability to obtain water-soluble nanocomposites containing vitamin E. Immobilization of vitamin C on the silica surface prevents its oxidation. Its interaction with the adsorbent surface leads to a decrease in proton-donor ability of the OH-groups involved in the oxidation of ascorbic acid. Elydrophobized silica nanocomposites are characterized by a prolonged desorption of immobilized vitamins. It has been shown that vitamin C does not lose its antioxidant properties after desorption. 

As for all additives, interactions with other additives in solution, Fig. 3.16, and competition for surface reaction sites together with the effect of environmental factors such as temperature, blow-by gases, water and fuel dilution have variable effects on the formation of the film. Because ZDDPs are much more widely used as antiwear performance additives compared to other classes of compounds, these additive effects will now be discussed in greater detail than has been the case for other classes of anti-wear/friction additives. In particular the influence of structure, concentration, dispersant, detergent, antioxidancy and friction modifier on friction and wear will be discussed. In addition the influence of NO c and H2O will be briefly illustrated. 

Due to the presence of amine compounds in formulations of a number of corrosion inhibitors of metals, they acquire an antioxidant property for thermoplastics entering into chemisorption interactions with metals. The effect of Cl (trade marks GRM, VITAL, IFHANGAZ, MSDA, NDA, VNHL-20) on thermal oxidation and thermal resistance of polymers has been described in [34]. For investigations 5-20 wt% of Cl were introduced into the composite via mechanical mixing with dispersed polymers followed by injection molding or hot pressing of the composition. 

It is important to ensure that the chosen surface treatment agent does in fact bind to the filler. If the additive does not bond to the surface then it cannot fulfil its function. Excess additive is, at best, a waste of money, but in some cases it may have worse consequences such as destabilising the polymer. For example, it has been shown that calcium stearate, a common dispersant, can destabilise polyolefins and cause yellowing, by interacting with the antioxidant [127]. 

Uses of 1. are numerous. The most important outlet is ->food additives. Due to its interaction with proteins, it is used in baked goods to improve volume, disperse fat easier and to act as an antioxidant. It... 

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