【摘要】 为了探索同时具有聚氧异丙烯基团（PO）和聚氧乙烯基团（EO）的延展型表面活性剂分子在聚甲基丙烯酸甲酯（PMMA）表面的润湿性调控机制，对5种具有PO基团和EO基团的阴离子延展型表面活性剂十八烷基-（聚氧异丙烯）_m-（聚氧乙烯）_n-羧酸钠(C₁₈PO_mEO_nCOONa,m=5、10、15和n=5、10、15)溶液在PMMA表面的润湿性进行测试分析，考察了PO基团、EO基团和表面活性剂浓度对表面张力(γ_LV)和接触角（θ）的影响，并计算黏附张力(γ_LVcos θ)、黏附功（W_A）和固液界面张力(γ_SL)等吸附参数。结果表明：表面活性剂浓度小于临界胶束浓度（CMC）时，C₁₈PO_mEO_nCOONa分子在溶液-空气界面和PMMA-溶液界面吸附，导致γ_LV降低，疏水烷基链朝向水相，导致γ_SL升高，两者共同作用导致θ不发生变化，维持在约75°；浓度大于CMC时，C₁₈PO_mEO_nCOONa分子在溶液-空气和PMMA-溶液界面同时达到饱和吸附，吸附参数趋于稳定；进一步增大浓度，C₁₈PO_mEO_nCOONa分子通过疏水相互作用在PMMA-溶液界面形成聚集体，亲水基团朝向水相，导致γ_SL迅速减小，θ急剧降低，C₁₈PO₅EO₁₅C的θ可降低至约43°。随着PO基团数量的增加，C₁₈PO_mEO_nCOONa在CMC时的γ_LV和高浓度时的θ逐渐升高；而随着EO基团数量的增加，γ_LV和θ几乎不发生变化。更多还原

【Abstract】 In order to explore the wettability regulation mechanism of extendable surfactant molecules with both polyoxyiso-propyl（PO）and polyoxyethylene（EO）groups on the surface of polymethyl methacrylate（PMMA）,the wettability of sodium octadecyl-（polyoxyisopropyl）_m-（polyoxyethylene）n-carboxylate(C₁₈PO_mEO_nCOONa,m = 5,10,15,and n = 5,10,15)solutions of five anionic extendable surfactants with PO and EO groups on the surface of PMMA was tested and analyzed. The effects of PO groups,EO groups,and surfactant concentrations on surface tension(γ_LV)and contact angle（θ）were investigated and the adsorption parameters such as adhesion tension(γ_LVcos θ),adhesion work（W_A）,and solid-liquid interfacial tension(γ_SL)were calculated. The results show that when the concentration of surfactant is less than the critical micelle concentration（CMC）,the C₁₈PO_mEO_nCOONa molecules adsorb at the solution-air interface and PMMA-solution interface,resulting in a decrease in γ_LV,hydrophobic alkyl chains facing the aqueous phase,and an increase in γ_SL. The θ stays consistent at about 75° due to these two important considerations. When the concentration is greater than CMC,C₁₈PO_mEO_nCOONa molecules form saturated adsorption films at both the solution-air and PMMA-solution interface,the interface adsorption parameters remain constant. As the level of concentration keeps increasing,C₁₈PO_mEO_nCOONa molecules con-tinue adsorbing at the PMMA-solution interface and aggregate structure is formed through hydrophobic interac-tion. The hydrophilic group confronting the aqueous phase leads to a rapid decrease in γSLand θ,the θ of C₁₈PO₅EO₁₅COONa can be reduced to roughly 43°. The γ_LV at CMC and the θ at high concentration gradually increase with the increase in the number of PO groups. However,the γ_LV and the θ barely alter when the number of EO groups increases.更多还原