Study of adsorption of nonionic surfactants at the liquid–solid interface by FTIR/CIR

Fourier transform infrared spectroscopy (FTIR), using the attenuated total reflectance (ATR) method, can be used to characterize the interface of a system. We investigated the adsorption at the liquid–solid interface of nonionic surfactant aqueous solutions with or without a hydrotropic agent. We studied monofunctional diblock copolymers of poly(ethylene oxide‐propylene oxide) (PEO–PPO) as nonionic surfactants and sodium p‐toluenesulfonate (NaPTS) as hydrotropic agent. The samples were analyzed by FTIR technique using the circular internal reflectance (CIR) accessory, which confirmed that the hydrotrope shifts the surfactant from the liquid–solid interface. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1668–1676, 2001     

SDS-PEG及SDS-PVP体系的聚合物相对分子质量阈值及表面活性剂临界浓度

用表面张力法研究了十二烷基硫酸钠 (SDS)与不同相对分子质量的聚乙二醇 (PEG)或聚乙烯吡咯烷酮 (PVP)的混合体系 ,实验结果表明SDS PEG或SDS PVP的表面张力 浓度对数 (γ lgc)曲线可以具有拟双平台 (或双拐点 )的特点。定义了聚合物相对分子质量阈值 [MP]这个聚合物结构特征常数 ,并发现实验用聚合物的相对分子质量必须超过该类聚合物的 [MP],其γ lgc曲线才可能呈现双拐点特点。实验结果同时显示SDS PEG体系中PEG的 [MP]为 2 0 0 0～ 40 0 0。具有双拐点的γ lgc曲线对应有两个表面活性剂临界浓度值c1和c2 ,且满足c1相似文献   

油溶型包桕脂烷醇酰胺一步合成研究

以中国乌桕脂为原料,用正交实验法在下对投料比、温度、催化剂用量和加料方式诸因素进行系统考察,取得由乌桕脂直接合成非水溶性乌桕民脂烷醇酰胺的优化工艺条件,乌桕脂收率达90％,具有可观的开发前景。     

基于分子动力学模拟的非离子表面活性剂对煤润湿性影响机制

煤矿深部开采条件下煤尘灾害严重,采用非离子表面活性剂可有效改善煤尘润湿性,抑制煤尘的产生和扩散。为了探究非离子表面活性剂对煤尘表面的润湿过程和润湿机理,采用分子动力学模拟和实验研究相结合的方法,研究非离子表面活性剂月桂基葡糖苷（APG）与曲拉通X–100（Triton X–100）对煤尘表面润湿性能的影响;基于苯环碳骨架结构建立3组煤–水界面吸附体系模型,对比分析表面活性剂在煤表面的吸附平衡构型和分子空间分布,计算煤–表面活性剂–水间相互作用能及能量组成变化,考察APG和Triton X–100与水分子形成氢键的能力;以河南平顶山矿区丁、戊、己3组煤层煤样为测试对象,开展沉降和接触角实验并计算煤样表面自由能组成,验证模拟结果,利用傅立叶红外光谱（FT–IR）测试煤样芳香烃基团特征,验证Triton X–100与煤分子间的作用机制。结果表明：达到吸附平衡状态时,非离子表面活性剂分子通过烷基链相互连接,形成聚集状态,在煤–水界面与水–气界面均有分布;Triton X–100通过增强与水分子的相互作用,促进水分子在煤表面的吸附,对煤表面润湿性能影响较大。室内试验结果表明,Triton X–100对煤表面的润湿效果优于APG,质量分数为1.5%时效果最优,且煤尘中的芳香烃含量越高,越利于Triton X–100的吸附。研究成果可为深部开采的高效抑尘剂研发提供理论指导和借鉴。     

烷基多苷的颜色及其脱色

烷基多苷中的残醇量、残糖量和总固体量对烷基多苷的颜色都有影响，残醇量的影响表现为产品的透明度；残糖量的影响表现为对产品的色泽，总固含量越低，越容易漂白，且透明度越高；同时，以H2O2为主要脱色剂，通过3种物质组成的复合添加剂加入H2O2体系中能显著提高脱色效果，消除了单纯用H2O2脱色产生的异味，脱色后产品对碱、热的稳定性良好。     

可聚合型非离子乳化剂合成及其在苯乙烯辐射细乳液聚合中的应用

为深入探讨细乳液稳定机理,本文设计合成了一种可聚合型的非离子乳化剂丙烯酸羟乙酯-2,4-甲苯二异氰酸酯-单甲基聚乙二醇(HEA-TDI-PEO),该乳化剂的亲水性和溶解度可通过改变PEO链分子量和总分子量进行调节。通过在苯乙烯辐射细乳液聚合中的应用研究发现,HEA-TDI-PEO在作为乳化剂的同时也能起到助稳定剂的作用,其聚合动力学符合细乳液液滴成核的特征,但聚合速率慢,转化率低。当PEO分子量为2000时,用HEA-TDI-PEO乳化剂配制的细乳液体系最为稳定,粒子形貌均一。这种可聚合的乳化剂可以减少环境污染,在工业生产中具有潜在的应用前景。     

Synergistic effect between amino sulfonate amphoteric surfactant and octylphenol polyoxyethylene ether (10) in aqueous solutions with different acidicities: consideration of different thermodynamic models

The micellization behavior of binary mixtures of sodium n‐dodecyl diamine sulfonate (C12AS) and octylphenol polyoxyethylene ether (10), OP‐10, in aqueous solutions at pH 3.5, 6.0, and 8.5 was investigated, and the values of mixed critical micelle concentration (C^M) were determined by both UV–vis spectroscopy using pyrene as a probe and by tensiometry. Within the framework of the pseudophase separation model, four thermodynamic models were adopted to describe the micellization parameters including the interaction parameters (β₁₂) between two surfactants, the components in real and ideal mixed micelles, the activity coefficients in mixed micelles, the thermodynamic parameters, and the thermodynamic stability. The experimental values of C^M, inferior to the ideal values, show nonideal mixing; the negative values of β₁₂ obtained from Rubingh's, Rodenas's, and Motomura's models mean the synergistic effect. Although there exist some divergences in the micellization parameters predicted by the three treatments, similar results were obtained, indicating the validity of these models in this investigation. Based on the calculation errors, Rubingh's model is best to describe the interacting behavior between the two surfactants in this investigation. Thermodynamic parameters predicted by the three treatments show a spontaneous process of micellization and an entropic contribution in the formation of mixed micelles. Different acidities of solutions result in different stabilities of micellization. The stability in feeble acidic solution is higher than in acidic or basic solution, and the stability in basic solution is slightly superior to that in acidic solution. All the above described phenomena can be explained rationally by the electrostatic effect of head groups of C12AS, the steric effect of head group for two surfactants, the molecular structures of surfactants, the influence of added counterion, and so on. © 2015 Society of Chemical Industry     

烷基多糖苷表面活性剂的研究进展

烷基多糖苷是一种温和的新型非离子表面活性剂,性能优越．应用日益广泛。本文综述了目前烷基多糖苷的合成方法、物化性能以及应用研究进展。     

非离子表面活性剂对污水聚合物热稳定性的影响

针对聚/表二元复合驱体系的长期热稳定性问题,在污水配制的聚合物溶液中加入非离子表面活性剂,研究其长期热稳定性及降低油水界面张力的程度。配制聚合物浓度为2 000 mg/L,非离子表面活性剂质量分数为0.10%和0.20%,在53 ℃无氧条件下恒温60 d。结果表明,非离子表面活性剂加入后,黏度保留率由22.3%提高到71.4%,恒温60 d后油水界面张力仍然保持在10?3数量级。现场采用该体系进行试注后发现,注入液可将油水界面张力降至2.59×10?3 mN/m;在油藏条件下,溶液经60 d老化后其黏度保留率达到72%;注入井注入压力较注聚/表二元体系前上升1 MPa。     

Clearning performance and foaming properties of lauroylamidopropylbetaine/nonionics mixed systems

Lauroylamidopropylbetaine (LPB) has good cleaning and foaming performance with excellent low skin irritation. We have investigated the relationship between cleaning performance and foaming properties of aqueous solutions containing binary and ternary LPB/nonionic surfactant systems. Foaming properties were evaluated by observing dynamic surface tension and aqueous core thickness of a vertical foam film measured by Fourier transform infrared spectroscopy. The LPB/lauroyldiethanolamide (LDE) system has a positive synergistic effect on cleaning performance and foam stability, estimated from the grease removal test and dishwashing test for a light-duty detergent. However, this system shows very poor initial foam performance in both the sponge test and Ross-Miles foam test. This disadvantage of the LPB/LDE system was improved using C12En (polyoxyethylene dodecyl ethers). Addition of C12En promoted dynamic surface tension lowering, indicating an improvement in the initial foaming performance, while maintaining cleaning performance and foam durability. Thus, the LPB/LDE/C12En ternary system has an excellent cleaning and foam performance as a light-duty liquid detergent.