Synthesis of a novel class of mixed-type surfmers and their properties in water

Abstract

Three new mixed-type surfmers were synthesized using poly(propylene oxide)/poly(ethylene oxide)/ poly(propylene oxide) (PPO-PEO-PPO) having terminal tertiary amine group as the basic material: (1) PPO-PEO-PPO with a carboxyl group on one end (MTA); (2) PPO-PEO-PPO with a quaternary ammonium group on one end (JTA); (3) PPO-PEO-PPO with a quaternary ammonium group on one end and a carboxyl group on the other end (MJTA). These products were confirmed by 1 H-NMR and FT-IR. Similar to PPO-PEO-PPO, the three surfmers have a cloud point (T cp ). Both MJTA and MTA have lower T cp than JTA. However, the cloud points of both MJTA-Na + and MTA-Na + are much higher than JTA. Their different T cp may be caused by their strength of dissociation in water. In addition, at a high temperature (T > T cp of MJTA), MJTA-Na + can be considered a pH-sensitive surfactant. At neutral and alkaline conditions, it can be used as an emulsifier. However, at acidic conditions, it loses its emulsification property. MTA-Na + has the same property.