A scaling law derived from percolation theory for the dissolution of phenolic resins in aqueous base is tested and confirmed on seven groups of amphiphilic resins. The scaling law can be presented in the dimensionless form: log(R/R1) equals 2 log[(p - pc)/(1 - pc)]. Here R and R1 are the dissolution rates of the resin and of a standard resin for which p equals 1, the percolation parameter, p, linked to the concentration of hydrophilic sites (OH-groups) in the material, and pc is the percolation threshold below which dissolution no longer occurs. In the group of resins of this study Pc equals 0.20. In its dimensionless form the scaling law provides a single function which applies to all resins of this study and, we believe, to amphiphilic resins in general. This allows the prediction of dissolution rates and the selection of polymer structures which are likely to have specified dissolution kinetics.
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