A COMPARISON OF BLOCK COPOLYMER SURFACTANT GELS

The aqueous gel forming properties of three series of block copolymer surfactants, poloxamers, poloxamines, and Butronic(R) polyols, are briefly reviewed and compared. The differences in their gel formation properties are explained. Aqueous gel formation of these polymers is attributed to the aggregation of extended linear coil micelles in which the hydrophilic ends become entangled as the temperature rises, due to dehydration. The failure of the Butronic polyol gels to exhibit the same reverse thermal behavior shown by the other two polyol series is attributed to a more lipophilic hydrophobe and to the larger number of moles of water associated with the Butronic hydrophile. The reverse thermal characteristics of aqueous poloxamer and poloxamine solutions has led to the development of aerosol detergent systems which can form foamy gels, thereby expanding the usefulness of these surfactants.