Figure 3.

(a) The concentration of the catalytic product, p-nitrophenol, as a function of time. ○, Catalysis by the gel; and ●, catalysis by an imidazole monomer solution. There is a marked increase in the catalysis rate by the gel in the shrunken state at 12.5 vol % ethanol. In the swollen state at 10 vol % ethanol, the reaction rate is small. (b) The initial reaction rate, V₀, as a function of ethanol concentration for catalysis by the gel (○) and imidazole solution (●). In parallel to the swelling and shrinking of the gel, the catalytic activity undergoes discontinuous but reversible change.