Pyridinium hydroxypropyl sulfobetaine

Pyridinium hydroxypropyl sulfobetaine (CAS 3918-73-8, EC 223-485-2), also referred to as PPS-OH or Quats 6.2, is a zwitterionic surfactant carrying both a permanent quaternary ammonium cation and a sulfonate anion within the same molecule. It carries no assigned E-code and is supplied as a transparent liquid.

In electronics manufacturing, PPS-OH functions as a leveling and wetting agent in electroplating baths, where its zwitterionic character reduces interfacial tension at metal surfaces to promote uniform copper deposition. In metalworking fluid formulations, it stabilizes oil-in-water emulsions by adsorbing at the oil-water interface, improving dispersion stability under high-shear conditions.

PPS-OH is available in industrial-grade liquid form and falls under REACH registration obligations for suppliers placing it on the EU market. Procurement teams should request a full SDS and confirm lot-specific purity data. Standard packaging formats vary by supplier; bulk and intermediate bulk container options are typical for industrial volumes.