Understanding acid-glycol switchable emulsifiers on the molecular scale.

Switchable emulsifiers are commonly studied at the macroscopic scale without significant insight into the molecular properties and processes underpinning their behaviour. This work aims to investigate on the molecular scale a switchable emulsifier comprising poly(methacrylic acid) (PMAA) and poly(ethylene glycol) methacrylate (PEGMA). This emulsifier forms stable oil/water emulsions at pH > 10, but the emulsion becomes unstable at pH < 3 due to droplet aggregation.

Aqueous Solutions of Associating Poly(acrylamide--styrene): A Path to Improve Drag Reduction?

Hydrophobically modified associating polymers could be effective drag-reducing agents containing weak "links" which after degradation can reform, protecting the polymer backbone from fast scission. Previous studies using hydrophobically modified polymers in drag reduction applications used polymers with ≥ 1000 kg/mol. Homopolymers of this high already show significant drag reduction (DR), and the contribution of macromolecular associations on DR remained unclear.