Kinetics, adsorption pretreatment effect

Additives to starch exert varying effects on the kinetics of water sorption. For example, lipids do not significantly affect the content of adsorbed water. The mode of starch defatting can also influence moisture sorption by molecules of the defatting solvent occupying active centers of sorption.389 The addition of either sucrose or lipids to starch has the same effect on both branches of the hysteresis curve.386,398 Some additives, such as dimethyl sulfoxide or ammonium rhodanide, induce selectivity of the adsorption and solvation of starch 411 Sulfur dioxide accelerates water sorption regardless of the temperature.412 Pretreatment of starch with sulfur dioxide usually increases the water sorption.413 Studies on the sorption of components of water-alcohol mixtures are discussed in Section IV. 

In either process, the rate of adsorption is expected to be extremely slow. Hence, the addition of an alkaline catalyst greatly aids in accelerating these adsorption processes. Heat and/or time can achieve the same viscosity reduction effect, because both increased temperature and prolonged time lead to more adsorbed silanes. Very few silane oligomers are produced in this method since the hydrolyzed silane molecules do not exist in quantity at any time of treatment. Unlike the mixing of a silane pretreated filler, it is essential to consider the kinetics of silane adsorption in this type of treatment method. 

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