Polymers have become one of the largest and most important materials we use in daily life. Their popularity has stemmed from their wide range of material properties combined with their low cost of production. Both of these attractive traits have in part been enabled by the development of catalytic polymerizations, which provide both high levels of control while also delivering high levels of productivity. In this Perspective, we highlight recent trends and achievements made in the growing field of catalytic polymerizations.

The acidity of a compound is a fundamental property that dictates molecular speciation and reactivity in solution. Measurements of acidity of simple molecules in interfacial environments are rarely carried out but assumptions often are made that the difference is sufficiently small that the change can be ignored. The effect of oil-surfactant-water interfaces in reverse micellar systems on the pKa value of the anilinium ion was measured using titrations by NMR spectroscopy as the size of the bis(2-ethylhexyl)sulfosuccinate (AOT)/isooctane reverse micelles decreased. The pKa was observed to drop from 4.85±0.02 to 4.62±0.02 in water as the reverse micelle decreased from w(0) 10 to 4 (that is down to a reverse micellar radius of about 2 nm). NOSEY experiments demonstrated that the aniline moiety resides within the surfactant interface with the amine/ammonium moiety protruding into the waterpool bridging the interface. The presence of the aniline was found to have modest and variable effect on the size of the reverse micelles as observed using dynamic light scattering. Our experimental results provide information important to theoretical studies, which explore interface phenomena and provide a framework for information on such simple molecules. These studies quantitate the small but significant effect on the pKa values upon placement of an aromatic amine molecule at a hydrophilic-hydrophobic interface.

Functionalizing inorganic particles with organic ligands is a common technique for heterogenizing organometallic catalysts. We describe how coordinating molecular platinum to silica nanoparticles functionalized with a high density of norbornene ligands causes unexpected latency of the catalytic activity in hydrosilylation reactions when compared to an identical reaction in which the norbornene is not tethered (2 % vs 97 % conversion in 1 h). Performing the hydrosilylation at elevated temperature (70 °C) suppresses this activity delay, suggesting the usefulness of this technique towards temperature-triggered catalysis. We demonstrate that this latency is related to ligand density on the particle surface, chemical structure of the norbornene, and silica nanoparticle topology. We also establish the benefit of this latency for triggered curing of silicone elastomers. Overall, our work establishes the noninnocent role of inorganic supports when functionalized with organometallic complexes.

Functionalizing inorganic particles with organic ligands is a common technique for heterogenizing organometallic catalysts. We describe how coordinating molecular platinum to silica nanoparticles functionalized with a high density of norbornene ligands causes unexpected latency of the catalytic activity in hydrosilylation reactions when compared to an identical reaction in which the norbornene is not tethered (2 % vs 97 % conversion in 1 h). Performing the hydrosilylation at elevated temperature (70 °C) suppresses this activity delay, suggesting the usefulness of this technique towards temperature‐triggered catalysis. We demonstrate that this latency is related to ligand density on the particle surface, chemical structure of the norbornene, and silica nanoparticle topology. We also establish the benefit of this latency for triggered curing of silicone elastomers. Overall, our work establishes the non‐innocent role of inorganic supports when functionalized with organometallic complexes.