Time‐lapse thiol‐acrylate polymerization using a pH clock reaction

A clock reaction, which involves a rapid increase in pH after a programable interval, may act as a “time-lapse” system for triggering the Michael addition polymerization of a trithiol and triacrylate dispersed in the clock reaction solution. The increase in pH catalyzes the addition of thiols to acrylates at the interface of the drops. The time-lapse period for the polymerization (as indicated by turbidity) was always longer than the induction period for clock in the same reactant concentrations condition. This is consistent with our claim that the polymerization was caused by the pH change.