Preparation And Properties Of New Type Wormlike Micelles

In this paper, two new types of wormlike micelles were prepared using zwitterionic and anionic surfactants. Zwitterionic surfactant is octadecyl hydroxy sulfobetaine(ODAHPS), the anionic surfactants refere to sodium octadecyl benzene sulfonate(SOBS) and dodecyl sodium sulfate SDS respectively. The temperature-responsive&salt-resistant and interfacial tension properties of the two types of wormlike micelle systems were studied.The first main job was to optimize the process of alkylbenzene. The purity of alkylbenzene was analyzed by MS. By experiment studyLthe best catalyst system was found and the high purity of alkyl benzene could be obtainedLso it was easy to lower the difficulty of sodium octadecyl benzene sulfonate!s purification process. The sodium octadecyl benzene sulfonate content was analyzed by two-phase titration. The purity of SOBS was above 99 %.The synthesis experiments of ODAHPS were carried out on the basis of previous work. Only one problem needed to be dissolved was the method to decrease the content of NaCl. The final ODAHPS purity determined by LC was above 99 %..The final surfactants and the intermediates were determined by FIR.Two zwitterionic and anionic surfactants wormlike micelle systems were received. The experiments showed that the best matching parameters respectively were XODAHPS/SOBS=7, XODAHPS/SDS=5. The temperature-responsive property, salt-resistant and alkali-resistant abilities, rheological property were studied. The two wormlike micelle systems were compared to illustrate the influence of alkyl chain length. The high content of ODAHPS-SOBS system was also be studied by rheometer.The study results showed that the two systems had temperature-responsive property. The responsive temperature was 50~. When the temperature was 50~, the systems with high viscosity were uniform and transparent, the viscosity decreased when rising temperature continuously. Viscosity became higher when surfactants content rised. Dynamic rheology measurement indicated that wormlike micelle stystems were viscoelastic solution. High content system was gellike liquid with low flow ability. The micelle systems appeared the typical shear thinning property that the wormlike micelles had. The two systems had excellent salt-resistant ability, the salt-resistant ability of ODAHPS-SDS was superior to that of ODAHPS-SOBS system. viscosity became higher fistly then decreased with the inorganic salts content rise. Monovalent metallic ion resistant capacity of the two system was much better than that of divalent metal. Combining the two systems with alkalinesurfactant-polymer flooding formula, the alkali-resistant capacity was also studied, to our satisfactionLthe two wormlike micelle systems had good alkali-resistant capacity.Interfacial tension was an important factor to assess a kind of surfactant. So we also did some research on interfacial tension. The results showed that interfacial tension value became higher when surfactants content rised. The ODAHPS-SOBS system could cooperate with whether strong alkali or weak alkali, interfacial tension value could reach 10-3 mN m-1. The ablity of ODAHPS-SOBS system to lower interfacial tension was superior to that of ODAHPS-SDS system. Strong alkali wormlike micelle system was conductive to low interfacial tension. Salt was helpful to reduce the interfacial tension.