Nonionic polymers, dispersing agents

All dispersing agents are surface active and they can be simple surfactants (anionic, cationic, zwitterionic or nonionic), polymers or polyelectrolytes. The dispersing agent should be soluble (or at least dispersible) in the liquid medium and it should adsorb at the solid/liquid interface. 

Many drug carriers are made of hydrophobic materials such as lipids and poly(butyl cyanoacrylate). It will be thermodynamically unstable for submicron particles made of these materials to remain dispersed in an aqueous environment such as blood circulation. Surfactants or block co-polymers are therefore routinely included in these formulations to prevent particle aggregation. Studies showed that a number of these agents, most noticeably the nonionic surfactants such as polysorbates (also known as Tweens) and Tritons and block co-polymers such as poloxamers (also known as Pluronics), may inhibit the ABC transporters [97-99]. As previously discussed, ABC transporters interact with their substrates in the lipid bilayers of the plasma membrane. Surfactants can disrupt the arrangement of the lipid bilayer expressing the transporters and subsequently inhibit their drug efflux activities [97, 100]. It... 

Uses Dispersant, wetting agent, emulsifier for pojymerization, emulsion paints, brush cleaners, wallp er removers, pigment preps., binder emulsions surfactant costabilizer to inc. mech. or salt stability of polymer disps. emulsifier for mfg. of o/w emulsions food pkg. adhesives, paper/paperboard emulsifier in mfg. of food-contact articles Regulatory FDA 21CFR 175.105,176.180,178.3400 BGA approved Properties Clear liq. dens. 1.022-1.026 g/cm (70 C) FILB 13.4 hyd. no. 84-91 set pt. 7 C doud pt. 60-65 C (1 g/99 cm water) nonionic 99% min. act. <0.5% water... 

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