Study On The Synthesis And Solution Properties Of Bola Polyurethane Surfactants

The chemical structure consists of two hydrophilic groups connecting with ahydrophobic chain is Bola surfactant. Due to the two polar hydrophilic head groups, it hasgood solubility in water and the micelles has good stability in water. Bola surfactant can beused in some special field （such as drug delivery, simulation of biological membrane, etc）, hasattracted the attention of scholars at home and abroad.Based on the above advantages, three new Bola polyurethane surfacents with differentlength of hydrophilic chain were synthesized with the advantage of Bola surfactant, polymericsurfactants and polyurethane surfactant. In the synthesis process, by changing water and oilchain segment ratio, three Bola type polyurethane surfactants was synthesized for the firsttime and the structure of products have been characterized by IR and1H NMR etc. Focuse onboth the Bola polyurethane surfactant solution properties. In addition, the solubilizationability of the Bola polyurethane surfactants were studied.The experimental results are as follows:â’ˆThis suspension loop method is used to test the surface tension of the new Bolapolyurethane surfactant under different conditions and to reflect the critical micelleconcentration by surface tension. The experimental results show that:â‘´In25oC secondary distilled water, as the hydrophilic segment growth, the criticalmicelle concentration is increasing, the CMC is1.60mol/L,5.27mol/L,9.81mol/L; thesurface tension was39.6mN/m,40.2mN/m,40.5mN/m.⑵When temperature is below the cloud point, as the temperature increases, the surfacetension and CMC of this kind of surfactants decreases.⑶The different electrolyte has different effect on the surface tension and criticalmicelle concentration.â‘ When the concentration of electrolyte （NaCl） in the range of0⁰.05mol/L, with the increase of electrolyte concentration, surfactant solution surface tension and critical micelle concentration gradually decreases; When the concentration of electrolytes（NaCl） in the range of0.1⁰.5mol/L, the change of surfactant solution surface tension andcritical micelle concentration is very small as the change of electrolyte concentration.â‘¡Fordifferent electrolyte solution, at the same ionic strength, different salts have different effectson the surface tension and CMC. At the same intensity of cations （Na⁺）, as the anionic （e.g. F^-,Cl^-, Br^-and I^-） charge/radius ratio decreases, critical micelle concentration increased gradually;At the same intensity of anion （Cl^-）, as the cation （e.g. K⁺, NH₄⁺and Na+） charge/radius ratioincreases, the critical micelle concentration decreased gradually.â’‰Ubbelohde viscometer is used to test the Bola polyurethane surfactant solution’sviscosity behavior in different concentrations. The experimental results show that: When thesurfactant concentration above the CMC, similar to ordinary small molecular surfactants, therelative viscosity is a linear relationship with the concentration of the surfactant. With the lossof the surfactant concentration, the relative viscosity of solution also gradually reduced.Continue to reduce the concentration of the surfactant, the relative viscosity will appear firstdecreases and then increases when the surfactant concentration near the CMC. With the lossof the surfactant concentration, the relative viscosity of solution increased gradually.Experimental result shows that the relative viscosity of the surfactant solution is differentfrom the ordinary small molecular surfactants, when the concentration near the critical micelleconcentration and less than the critical micelle concentration. Respectively, this paper uses theideas of the critical concentration and adsorption to explain this anomaly.â’ŠUsing the turbidity method to study the solubilization. With the increasing ofhydrophilic segment, solubilization capacity decreases gradually and the capacity of toluenesolubilization is better than OP-10. This kind of surfactant is established for possiblesolubilization model of toluene.â’‹This topic also studied the new synthetic surfactant part of other properties:Emulsifying performance is better than traditional surfactant OP-10and the longer thehydrophilic segment is, the better emulsification effect is; Cloud point with the increase ofhydrophilic segment increasing,86oC,92oC and92oC respectively.