The combination of UV curing and a new phosphonium borate salt has enabled the production of tough polyelectrolyte films in a single step, as described by B. M. Berven, P. J. Ragogna, et al. on page 499. A series of new polymerizable anions Na[BPhxSty4-x], x = 0–3, are prepared in high yields with 1–4 para-vinylphenyl units incorporated onto the boron atom, and these borates have the potential to be paired with a wide variety of cationic units. Pairing with a polymerizable phosphonium cation gives a series of organic salts that are directly polymerized by UV curing, affording highly crosslinked polyelectrolyte films that do not require the usual substrate pre-treatment (glass) or instillation of an anchoring layer. The mechanical properties of the polymeric materials could also be tailored by the anion functionality, as demonstrated by the increased scratch resistance as the crosslink density increased.