表面活性剂的性能与应用(Ⅷ)——表面活性剂的蠕虫状胶束及其应用

首先简单介绍了表面活性剂蠕虫状胶束的结构和形成,列出了常见的表面活性剂蠕虫状胶束体系,重点阐述了蠕虫状胶束的基本性质和常用的研究手段,最后着重综述了表面活性剂蠕虫状胶束在采油领域的应用。     

简述离子表面活性剂构筑蠕虫状胶束的研究现状

粘弹性蠕虫状胶束具有特殊的微观结构,其流变性能在不同领域具有重要的应用。本文介绍了表面活性剂构筑的蠕虫状胶束的结构特点、应用及研究现状。传统离子表面活性剂构筑蠕虫状胶束通常需要一些外加作用,Gemini表面活性剂因其结构优势,可以自身形成蠕虫状胶束。     

水相和特殊介质中有序聚集体的结构、性质和应用(Ⅱ)——表面活性剂蠕虫状胶束

综述了近来关于表面活性剂蠕虫状胶束相态、平衡状态和动态的理论和实验结果以及应用冷冻蚀刻电镜照片直接观察到其结构。在一定条件下,表面活性剂在溶液中能可逆地缔合成为一种长的、有柔性的、甚至网状的蠕虫状胶束。它们具有类似柔软的高聚物溶液的线性黏弹性质,然而蠕虫状胶束经历裂解和再组合过程而表现复杂的流变性。最后介绍了蠕虫状胶束在油田、减阻剂和日用化工等方面的应用。     

阴离子表面活性剂和盐析类电解质对非离子表面活性剂相行为的影响(英文)

探讨了阴离子界面活性和盐析类电解质 (特别是直链烷基苯磺酸钠 (NaLAS)和柠檬酸钠(NaCitrate)对于市售非离子表面活性剂C12～ 15E〈7〉相行为的影响。对于相图中六角形和薄板液晶态的范围和微胞不互溶区的位置 ,NaLAS和NaCritate展现出定性上不同的影响。加入NaLAS提高了L1′ L1″生成的混浊温度和协助了H1相的形成 ,但它缩小了Lα 相的范围。加入NaCritate降低了L1′ L1″生成的混浊温度和缩小了H1相的范围 ,但它协助了Lα 相的形成。就效用上来说 ,NaLAS和NaCritate的存在可以被视为改变C12～ 15E〈7〉的亲水性质 :NaLAS增加了表面活性剂的亲水性和NaCritate降低了该项性质。在C12～ 15E〈7〉/NaLAS -H2 O系统中 ,NaLAS的效用可以通过加入NaCritate而中和 ;相行为回归到原来的C12～ 15E〈7〉-H2 O。这些相行为的改变是由于阴离子表面活性剂的静电性质和盐析类电解质的疏水效应引起的     

新型拟双子表面活性剂构筑的蠕虫状胶束及其pH和温度响应行为（英文）

将短链二元酸(丁二酸(SA)、戊二酸(GA)、己二酸(AA))和长链N-(3-(二甲基氨基)丙基)硬脂酰胺(C18N3N)以1∶2的摩尔比混合,通过静电相互作用,构筑了三种新型的拟双子表面活性剂。该过程无需复杂的合成。通过表面张力仪和流变仪测试了该系列表面活性剂的表面活性和流变性能。结果发现,2C18N3N/GA拟双子表面活性剂的cmc为4.60×10^-5 mol/L,该值远低于传统双子表面活性剂,说明构筑的拟双子表面活性剂2C18N3N/GA具有很强的胶束聚集能力,2C18N3N/SA和2C18N3N/AA体系也具有类似的特征。在浓度超过50 mmol/L时,该系列表面活性剂可形成蠕虫状胶束,溶液表现出黏弹行为,且黏弹溶液具有较好的耐温耐剪切性能。还考查了上述黏弹溶液的pH和温度响应性,发现体系pH为6.1时,溶液黏度很高,pH为4.0或9.3时,黏度下降。随着温度的升高,体系的黏度也会迅速增加。在60℃时,该体系的零剪切黏度可高达11 967.73 Pa·s。该表面活性剂制备简单,性能优良,拓展了新型表面活性剂的制备方法和应用范围。     

阴离子表面活性剂(AS)的测定方法研究

阴离子表面活性剂(AS)能改变两相间的表面张力,具有润湿、起泡、洗涤的作用。阴离子表面活性剂(AS)随着生活废水排放到环境中会导致水质恶化,进而对水生生物和环境造成危害,阴离子表面活性剂已成为水体污染的监测指标之一。笔者介绍了近年来阴离子表面活性剂的测定方法,如共振光散射法、流动注射分析法、色谱法、紫外分光光度法、可见分光光度法、荧光光度法和联用法,并对今后阴离子表面活性剂检测方法的研究方向提出了建议。     

表面活性剂协同效应的研究(英文)

新型表面活性剂的开发研究及现有品种的复配是表面活性剂研究领域中的两个主要方向。对洗涤剂中常用的表面活性剂 :烷基聚氧乙烯醚硫酸钠 (AES)、椰子油酰胺丙基甜菜碱 (KBT)和椰子油二乙醇酰胺 (CDEA)的复配进行了研究。采用滴体积法测定了混合溶液AES/KBT和AES/CDEA的表面张力σ ,再根据σ与溶液浓度C曲线 ,求得溶液的临界胶团浓度cmc、C =cmc时溶液的表面张力σcmc及σ =35mN·m-1时溶液的浓度C35。溶液的起泡性和泡沫稳定性则利用根据Ross -Mile原理自制的装置来测定。实验结果显示 ,在一定混合比时 ,混合溶液的cmc值比相应的任一纯组分的cmc0i 都要低 ,C35也低于纯组分的C035,说明两复配体系均有形成胶团和降低表面张力效率的协同效应。最小cmc值所对应的复配比例 (摩尔比 )为AES/KBT =0 46∶0 5 4,AES/CDEA =0 42∶0 5 8。实验结果还显示 ,混合溶液的起泡性和泡沫稳定性均有改善 ,特别是泡沫稳定性     

镧(Ⅲ)离子和非离子表面活性剂对铝的缓蚀协合效应

用失重法研究了在盐酸介质中 ,稀土镧 ( )离子对铝腐蚀速度的影响以及L a3 和非离子表面活性剂聚乙二醇辛基苯基醚 ( OP)对铝的缓蚀协合效应 ,发现L a3 对铝有较强的增蚀作用 ,而 La3 和 OP则表现出显著的缓蚀协合作用     

离子液体表面活性剂的合成与应用(Ⅰ)——离子液体表面活性剂的结构和分类

在介绍了离子液体的结构特点和特性的基础上,重点综述了离子液体表面活性剂的结构特征,并且按阳离子型、阴离子型、两性型、双子型和Bola型五类分别介绍了离子液体表面活性剂的典型结构和文献发表的主要品种,显示了离子液体表面活性剂具有较强的结构可设计性和未来品种的多样性。     

Rheology of concentrated sulfonated poly(ether ether ketone) solutions

Sulfonated polyether ether ketone (SPEEK), an ionic polymer, has been shown to be a potential candidate for fuel cell electrolyte as a proton exchange membrane. Rheological behavior of SPEEK solutions is of great interest to understand the molecular associations as well as due to implications in membrane processing. In this work, SPEEK of various degrees of sulfonation (58–80) was prepared and rheology of concentrated solutions of SPEEK was studied. The rheological properties were evaluated using steady and oscillatory shear. It was found that steady shear viscosity and storage modulus at any given concentration, is the highest for the lowest degree of sulfonation SPEEK solutions in N‐methyl‐2‐pyrrolidone. The low frequency plateau in storage modulus was observed at some combinations of degrees of sulfonation and concentrations, indicating gel‐like behavior in these SPEEK solutions. No significant change in rheological behavior was observed with different polar solvents. Increase of several orders of magnitude in viscosity, storage and loss moduli were observed with increasing concentrations. The role of hydrophobic aggregation and inter‐chain associations in determining rheology of SPEEK solutions is argued based on comparisons with other material systems. The rheological behavior of SPEEK solutions with 70 as the degree of sulfonation, suggests crossover from hydrophobic‐hydrophilic balance. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40044.     

油酸钠蠕虫状胶束的性质及驱油效率研究

分别通过稳态、动态流变的方法和冷冻蚀刻透射电镜、室内模拟驱油实验和平板夹砂微观模型驱油实验,研究了由碳酸钠诱导形成的油酸钠蠕虫状胶束的流变学性质及形貌和蠕虫状胶束驱油配方的驱油效果及驱油微观机理。结果表明,在油酸钠(NaOA)溶液中,加入一定量的Na2CO3能够形成蠕虫状胶束;孤岛东区稠油注聚驱后,蠕虫状胶束驱油配方(w/%,1.83 NaOA 4.24 Na2CO3)的室内模拟驱油可提高采收率25%原始石油地质储量(OO IP);平板夹砂微观驱油模型显示蠕虫状胶束驱油体系进入模型中,能够使注聚后束缚残余油重新启动、变形,渐渐形成油墙向出口处运移,蠕虫状胶束驱油体系能够有效扩大波及体积,提高洗油效率,从而提高驱油效率。     

Preparation and characterization of hyperbranched poly(ether sulfone) and its application as a coating additive for linear poly(ether sulfone)

Hyperbranched poly(ether sulfone) (HPES), a suitable coating additive for improving the rheological properties of linear poly(ether sulfone) (LPES), was easily produced via polymerization of commercially available bisphenol S (A₂ monomer, BPS) and synthesized 2,4′,6‐trifluoro‐phenylsulfone (BB′₂ monomer, TF). During this reaction, fluoro‐ or phenolic‐terminated HPES (F‐HPES or OH‐HPES) could be facilely obtained by controlling the feed mole ratios of the two monomers. The polymerization mode A₂ + BB′₂ was confirmed by analyzing the model compounds and the degree of branching (DB) was calculated systematically. In addition, the synthesized polymers' chemical structures were exhibited by FTIR, ¹H NMR as well as ¹⁹F NMR spectroscopy. Notably, the addition of 1 wt % HPES reduced the melt viscosity and improved the high temperature liquidity of LPES because of its unique spherical shape. Furthermore, the addition of HPES did not have a negative impact on the performance of LPES, which was attributed to the good miscibility between HPES and LPES. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43892.     

Evaluation of an onset of electrospun beadless poly(ethylene oxide) nanofibres

To evaluate the lowest polymer concentration within a solvent from which there appears beadless nanofibres during the process of electrospinning, is rather complicated. A widely used method is based on a determination of so called entanglement concentration c_e and the onsets of beadless nanofibres are characterized by multipliers of c_e subjected to used materials. However, a determination of c_e as an intersection point of two linear segments (in log–log coordinates specific viscosity vs. concentration) in a semi-dilute region is not applicable for all materials as for instance a solution of poly(ethylene oxide) (PEO) in water does not exhibit 'classical' three linear segments within the dilute and semi-dilute regions determining overlap and entanglement concentrations. For such cases a new approach for the evaluation of an initial concentration from which beadless nanofibres are produced is proposed. This method does not use the terms overlap and entanglement concentrations. The procedure is demonstrated using four PEO solutions differing in molecular weight. The relationship expressing initial concentration in dependence on PEO molecular weight containing no adjustable parameters is proposed.     

The Formation of pH-Sensitive Wormlike Micelles in Ionic Liquids Driven by the Binding Ability of Anthranilic Acid

Wormlike micelles are typically formed by mixing cationic and anionic surfactants because of attractive interactions in oppositely charged head-groups. The structural transitions of wormlike micelles triggered by pH in ionic liquids composed of N-alkyl-N-methylpyrrolidinium bromide-based ILs (ionic liquids) and anthranilic acid were investigated. These structures were found responsible for the variations in flow properties identified by rheology and dynamic light scattering, and account for the structures observed with cryogenic transmission electron microscopy (Cryo-TEM). High-viscosity, shear-thinning behavior, and Maxwell-type dynamic rheology shown by the system at certain pH values suggested that spherical micelles grow into entangled wormlike micelles. Light scattering profiles also supported the notion of pH-sensitive microstructural transitions in the solution. Cryo-TEM images confirmed the presence of spherical micelles in the low-viscosity sample and entangled wormlike micelles in the peak viscosity sample. Nuclear magnetic resonance spectroscopy analysis revealed that the pH sensitivity of ionic liquid systems originated from the pH-dependent binding ability of anthranilic acid to the cationic headgroup of ionic liquids.     

Gelation and crosslinking characteristics of photopolymerized poly(ethylene glycol) hydrogels

The gelation and crosslinking features of poly(ethylene glycol) (PEG) hydrogels were scrutinized through the UV polymerization processes of poly(ethylene glycol) methacrylate (PEGMA) and poly(ethylene glycol) dimethacrylate (PEGDMA) mixtures. The real‐time evolutions of the elastic moduli of the prepolymerized mixtures with different crosslinking ratios of PEGMA and PEGDMA and the photoinitiator concentrations were measured during photopolymerization. The rheological properties were compared with other properties of the PEG hydrogels, including the relative changes in the C?C amounts in the mixtures before and after UV irradiation, water swelling ratio, gel fraction, mesh size, and mechanical hardness. As the portion of PEGDMA as a crosslinker increased, the final elastic modulus and gel fraction increased, whereas the swelling ratio and scratch penetration depth at the hydrogel film surface decreased because of the formation of compact networks inside the hydrogels. These results indicate that there was a good correlation between the rheological analysis for predicting the crosslinking transition during photopolymerization and the macroscopic properties of the crosslinked hydrogels. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41939.     

Rheology and morphology study of immiscible linear low‐density polyethylene/poly(lactic acid) blends filled with nanosilica particles

The objectives of this study are to investigate the effect of silica nanoparticles on the morphology and rheological behavior of immiscible linear low‐density polyethylene/poly(lactic acid) (LLDPE/PLA) blends. Melt blending method is applied to prepare the blends and their nanocomposites. Scanning electron microscope and parallel plate rheometer were used to investigate morphology and rheological behavior of the blend nanocomposites. Scanning electron microscope results demonstrated a significant change in morphology behavior by incorporation of silica nanoparticles. A significant reduction in the PLA droplet for LLDPE/PLA (75/25) with 8 wt % silica was observed. The rheological studies illustrated that for all samples storage modulus and complex viscosity of blend nanocomposites are higher than neat blends. Finally, melt rigidity of blend nanocomposites was estimated by measurement of rheological properties using a rotational rheometer through small amplitude oscillatory shear experiments. As a result, through the shear data, a high value quantity as a criteria for melt rigidity is obtained for the LLDPE/PLA (75/25) with 8 wt % silica in comparing to the other samples. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45526.     

食品、化妆品和药剂化学中的流变学

本文主要介绍了食品,化妆品和药剂化学中乳液和凝胶化学品中流变学方面的进展。对于乳液,我们主要介绍其壁面滑移现象和非线性粘弹性的模型;对凝胶,我们重点放在了用盐提高其强度的方法上。     

Comparisons of the rheological behaviors of polypropylene and polymethyl methacrylate in a capillary die

In this study, the rheological characteristics of polypropylene (PP) melt at 210, 220, and 230 °C and polymethyl methacrylate (PMMA) melt at 230, 240, and 250 °C in a micro die were investigated. The experiments were performed over a shear rate range of 3 × 10² to 5 × 10³ s^?1 using an advanced twin‐bore capillary rheometer. Dies with diameters of 1.0, 0.5, and 0.25 mm were used. The results indicated that the geometric dependences of the PP and PMMA viscosities were not identical at different shear rates and temperatures and that the micro size effect had a profound influence on the PP viscosity. The analysis demonstrated that the variations in the shear viscosity of the PP and PMMA melts in the micro die were partially attributed to the contribution of the pressure applied to the polymer melts. Additionally, the effect of wall slip on the PP and PMMA viscosities in the tested dies was investigated based on the modified Mooney method. The results implied that wall slip easily occurred in the PP melt flowing through the 0.25 mm die at 210 °C due to the distinct size effect. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44617.     

Rheology of ordinary and low-impact environmental concretes

This study deals with the rheological properties of concrete mixtures incorporating various types of mineral additions as a partial replacement of cement in order to produce a low-impact environmental concrete. The control mixture contained only Portland cement as the binder, while the remaining mixtures incorporated binary cementitious blends of slag, limestone filler, and fly ash with different rates of replacement. After mixing, the plastic viscosity and yield stress of the concretes were evaluated at different slump values using a rheometer apparatus. The results showed that the type of mineral additions and the rate of substitution affect the rheological parameters of low-impact environmental concrete. Indeed, increasing the degree of substitution leads to an increase in the plastic viscosity of the concrete made with different types of additions used in this study.