Rebinder number

As in the case of the Fedorov number, the Rebinder number is independent of the choice of the heat and mass transfer potentials. This number is part of the fundamental heat balance of the drying process. Unlike the Pn number, the temperature-drying coefficient describes the changes occurring in the integral mean temperature (f) and in the mean moisture content (u). In other words, it relates the kinetic properties of integral heat with moisture transfer properties, whereas, the Pn number is concerned with local changes in u and t. 

The Rebinder (Rb) number is formulated using the methodology described above in item 5. This dimensionless number is given as the ratio between the dimensionless temperature coefficient of drying and the Kossovich number ... 

In addition to the torsion plastograph mentioned above, a number of other methods are used for appraising the properties of plastic bodies in practice. Plastic strength (rigidity) is determined by means of the Rebinder penetrometer which measures the depth of penetration of a cone forced into the body under constant load. The respective quantity is related to yield point. The commercial Brabender plastograph measures the resistance of mixture to kneading. The extrusion viscometer, from which the material is extruded under pressure, is analogous to flow-out viscometers. 

The covalent approach or the pre-organized approach implies the formation of a template-functional monomer complex through reversible covalent bonds prior to polymerization. After synthesis and removal of the template, in the subsequent rebinding step, the initial covalent linkage is reconstituted between the polymer and template. Therefore, only a low number of non-selective binding sites are expected to be formed because of the well-defined stoichiometry taking place between the functional monomer and template. Unfortunately, this approach is only applicable to a limited number of template molecules. 

Before the molecularly imprinted polymer may be used for rebinding studies, one step remains—extraction of the original template molecules from the polymer matrix. A number of extraction protocols have been developed for different imprinting procedures. In the covalent and metal coordination approaches, an appropriate reagent is needed to break the bonds formed between the template and the functional elements. For the noncovalent approach, a polar solvent, often... 

These polymers revealed higher uptake of ampillicin 24 compared to the nonimprinted polymer which has been prepared with both functional monomers but no template at all. Batch rebinding studies were undertaken in which around 20% of the template has been offered to the polymer (in relation to the number of free cavities). 

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