Study of the solution behavior of β-cyclodextrin amphiphilic polymer inclusion complex and the stability of its O/W emulsion

A supramolecular recognition system was constructed based on the host–guest interaction with water-soluble β-cyclodextrinpolymer-P(AM/A-β-CD/NaA) as the host polymer and hydrophobically modified polyacrylamide-P(AM/C18/NaA) as the guest one. The guest polymer contains a small amount of hydrophobic octadecyl groups. High viscosity enhancement was observed when P(AM/A-β-CD/NaA) was added to P(AM/C18/NaA) solution, the concentration of P(AM/C18/NaA) was under the critical aggregation concentrations (CAC), as a result of the polymer inclusion association. The influences of salt concentration, shearing, pH values and temperature on the viscosity of mixture solution were also studied. O/W crude oil emulsion stabilized by the complex was prepared. A laser particle size analyzer and Turbiscan Lab Expert stability analyzer were employed to study their stability. The results indicated that mixture emulsion became more stable than the single amphiphilic polymerʹs. This is because that the net structure of elastic polymer in the continuous phase has the ability to hold oil droplets at the low concentration of P(AM/C18/NaA). The stability mechanism of O/W emulsion was indicated by three-stage visual rheological method. In this paper, the stability of inclusion complex is discussed, and the mechanism of the enhanced oil emulsification is further explored.