| It is valuable in theory and practice to design surfactants for special application fields. Many researches had shown that surfactants with branches can reduce surface tension obviously and the anionic surfactants with oxyethylene can also highly improve the surface property, which may break a new path to design surfactants for Enhanced Oil Recovery (EOR). The studies on anionic surfactants with oxyethylene in the branches are rarely reported, which leads to lacking systematical knowledge in the relationship of the molecular structure and performance of this kind of surfactants. The few researches have indicated that the anionic-nonionic arylalkyl sulfonates, containing oxyethylene in the branches, performed better interfacial properties, which made them potential candidates for a wide variety of surfactant applications in EOR. In the dissertation, the anionic arylalkyl sulfonated surfactants with oxyethylene in the branches, sodium octyl-[ω-octyloxy-poly(oxyethylene)]yl-benzene sulfonates ,have been synthesized and their properties have been studied systematically. The experiments and results are as following:The sodium octyl-[ω-octyloxy-poly(oxyethylene)]yl-benzene sulfonates were synthesized from fatty , phenol ,multiethylene glycol and alkyl bromide through several processes, including acylation, esterification, Fries rearrangement, Pd-catalyzed hydrogenation, Williamson ether synthesis and sulfonation. The structures were characterized by FT-IR, 1H NMR, and ESI-MS methods. The results suggested that the structures of the compounds with high purity are definite.The surface and interfacial tensions of sodium octyl-[ω-octyloxy-poly(oxyethylene)] -yl-benzene sulfonates in aqueous solutions have been investigated by Wilhelmy plate method and spinning drop method respectively to study the effect of the length of hydrophobic group and the number of EO units on their properties. It was discovered that the surface performance of these surfactants is greatly outstanding: the values of critical micelle concentration reached to be of the order of magnitude of 10-5 mol/L, the values of theγCMC is between 25 to 31 mN/m.and the efficiency of surface tension reduction is excellent. With the increasing in EO chain length, the CMC slightly changed after the first decrease, On the other hand, theΓmax decreased after the first increase andγCMC increased after the first decrease accordingly.The appropriate EO chain length is the key facter to get the best physicochemical properties.The carbon number of alkyl increased with 4 EO units in octyl-[ω-octyloxy-poly(oxyethylene)]-yl -benzene sulfonate ,however, the CMC andγCMC decreased and theΓmax increased.The interfacial tension is greatly affected on the EO chain length and the ultra low interfacial tension could be achieved in the water-crude oil weak alkali system with 0.05wt% sodium octyl-[ω-octyloxy-poly(oxyethylene)]-yl-benzene sulfonate containing 2 EO units,which proved its excellent effectiveness and efficiency of interfacial tension reduction.The dilational viscoelastic properties of sodium octyl-[ω-octyloxy-poly(oxyethylene)] -yl-benzene sulfonates at air-water were investigated by means of two methods: the interfacial tension response to sinusoidal area variations and interfacial tension relaxation method respectively. The dilational modulus and phase angle changed regularly with changing of concentration and frequency: the dilational modulus and viscosity increased with the frequency increasing as well as the surface dilational modulus passes through a maximum value with the increasing concentration. The max dilational modulus values of sodium octyl-[ω-octyloxy-poly(oxyethylene)]yl-benzene sulfonates at 0.1Hz passes through a maximum value (EO=2) with the increasing of EO chain and continue increase with length of alkyl group increasing. The results of interfacial tension relaxation showed that there will be three relaxed process: the exchange between surface and bulk, the conformational change of hydrophobic branch, the rearrangement of surface adsorbed film. The foam properties of sodium octyl-[ω-octyloxy-poly(oxyethylene)]yl-benzene sulfonates in the aqueous solution at different physicochemical condition were measured by air flowing method. It was found that the foam ability and foaming stability increase sharply with increasing surfactant concentration and then generally reached a plateau. The foam ability increased first and slightly changed (EO=2) while the foam ability continues increased with increasing of EO chain length.The foam ability decreased with the increasing of alkyl chain length,. however, the foam stability is on the contrary way. The foaming ability increased with the temperature increasing, while the foaming stability showed opposite tendency. The foaming stability was greatly decreased when NaCl was added, while the effect can improved by the introducing of the EO chian to the surfactant molecular.The micellezation and aggregation properties of sodium octyl-[ω-octyloxy-poly(oxy -ethylene)]yl-benzene sulfonates in aqueous solutions were investigated by fluorescence spectra of intrinsic probe. It's shown the CMC got by fluorescence spectra of intrinsic probe method is accordance with the CMC measured by surface tension method. The aggregation number N, characterized by quenching the fluorescence spectra with methyl viologen (MV2+) as the extrinsic quencher, gradually decreased first(from 0 to1) and then slight changed (from 1 to 4)with increasing of EO chain length.
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