Emulsification and Foaming Properties of Hydrophobically Modified Gelatin

Surface active gelatins were formed by covalent attachment of hydrophobic groups to gelatin molecules by reactingN-hydroxysuccinimide esters of various fatty acids (C₄–C₁₆) with the lysine groups. The surface activity was evaluated by emulsification and foaming properties, and by adsorption at the oil–water interface. It was found that, in general, the modified gelatins are more surface active than the native gelatin. The increase in hydrophobic chain length and the number of attached alkyl chains per gelatin molecule leads to a decrease in the emulsion droplet's size and to more stable emulsions. Adsorption isotherms, at the o/w interface, show much higher surface concentration, at saturation, of the modified gelatin than the native gelatin. The modified gelatins also have high foaming ability and a high foam stability, while the maximal foam activity is obtained by the C₈modified gelatin. The foaming properties of the surface-active gelatins were also compared to that of sodium dodecyl sulfate (SDS) and it was found that below the CMC of SDS, both foam activity and stability were higher for the modified gelatins. On the other hand, above the CMC the foam activity of SDS was higher, but the foam stability was lower than for C₈–C₁₆-modified gelatins.     

丙烯酸改性松香双季胺盐阳离子表面活性剂的结构与性能

研究了以丙烯酸改性松香为原料合成新型丙烯酸改性松香双季胺盐型阳离子表面活性剂的工艺,测定了它们的理化性质和表面性能,诸如含水量、含N量、阳离子活性物含量、Krafft点、表面张力、乳化力、泡沫力及泡沫稳定性等,表明它们具有良好的表面活性,并对其进行了红外光谱表征。     

Synthesis and performance of a series of dual hydroxyl sulfobetaine surfactants

Five kinds of dual hydroxyl sulfobetaines with different carbon atom numbers in hydrophobic chain were synthesized by using linear saturated alcohol, epichlorohydrin and dimethylamine, and then their structures were characterized by FTIR and ¹H NMR. The stability of all synthesized betaine surfactants in hard water was at level 4, which indicated they had high tolerance on hard water. Their CMC and γ_cmc were lower than the conventional cationic surfactant dodecyltrimethylammonium bromide and anionic surfactant sodium dodecyl, so they had more excellent surface activities. With the chain length increasing from C₈ to C₁₄, the surface activities, emulsifying properties and foaming properties of these betaine surfactants improved because surfactant molecules tightly arranged in the oil-water interface, but there was abnormal phenomenon of surface activity and foam property from C₁₄ to C₁₆ due to overlong hydrophobic chain. According to the results of the experiment, C₁₄SB was the most practical in the five kinds of surfactants, which was potential candidate to enhance oil recovery in oil field. The performances of C₁₄SB were as follows: CMC?=?2.2?×?10^?4?mol/L, γ_cmc?=?30.9 mN/m and the time of bleeding 10?mL water t?=?375?s at 2?g/L the optimum emulsification concentration.     

Adsorption,wetting, foaming,and emulsification properties of mixtures of nonylphenol dodecyl sulfonate based on linear alpha-olefin and heavy alkyl benzene sulfonate

Nonylphenol dodecyl sulfonate (C₁₂NPAS) has been synthesized, and mixed with heavy alkyl benzene sulfonates (HABS) in different proportions. The effects of different mixing ratios on properties such as adsorption, wetting, foaming, and emulsification, of the C₁₂NPAS/HABS surfactant mixtures have been systematically investigated. Experimental results have shown that, after mixing, the wetting and foaming properties of C₁₂NPAS/HABS are improved remarkably. Compared with C₁₂NPAS and HABS alone, the adsorption and emulsifying properties of C₁₂NPAS/HABS are far superior, which we attribute to a synergistic effect between these surfactants.     

新型孪尾Gemini两性离子表面活性剂应用性能

分别采用改进的Ross-Miles法及分水时间法,对3种新型孪尾Gemini两性离子表面活性剂(C8C8L3Sz、C8C8L4Sz和C10C8L3Sz)的泡沫性能及乳化性能进行了研究,并考察了表面活性剂浓度、分子结构和温度等对其的影响。 结果表明,该系列表面活性剂具有较好的泡沫性能,且随其浓度的增加,泡沫最大高度和半衰期均存在一个稳定值,疏水链越长,其起泡性能越差,泡沫稳定性越好;温度升高,起泡性能变好,泡沫稳定性变差;当表面活性剂浓度一定时,体系中加入低浓度的短链醇及无机盐均能提高泡沫的稳定性;C8C8L3Sz、C8C8L4Sz和C10C8L3Sz作乳化剂的最适宜的用量分别为6×10-4、6×10-4和4×10-4 mol/L,疏水基越长,乳化性能越好,而连接基对其影响较小;温度升高,乳化性能变差;当油相烷烃碳数相同时,环烷烃要比直连烷烃更易达到最佳乳化效果,但二者的乳状液稳定时间相当;对于油相烷烃碳数不同时,烷烃的碳链越长,乳状液的稳定性越差,乳化效果越不好。     

芳基油酸酰胺羟丙基磺基甜菜碱的合成及性能

合成了3种具有不同疏水基团的新型磺基甜菜碱两性表面活性剂,通过红外光谱对它们的结构进行了表征。 用滴体积法测定表面活性剂水溶液在25 ℃下的表面张力,从而确定其临界胶束浓度(cmc)及临界胶束浓度下的表面张力(γcmc);采用罗氏泡沫仪考察了浓度、温度对其泡沫性能的影响;采用分水时间法考察了其乳化性能。 结果表明,随着芳环在烷基链中的体积增大,cmc以及γcmc增大,饱和吸附面积Amin增大,而饱和吸附量Γmax减小。 3种表面活性剂的起泡性随浓度增大而增加,到一定值后趋于稳定;泡沫稳定性随浓度增大逐渐增强;起泡性随着温度的升高而显著增加,泡沫稳定性随温度升高而显著降低。 3种表面活性剂的乳化能力随浓度增大而逐渐增强然后趋于稳定。     

Novel Cationic Gemini Surfactants Based on Piperazine: Synthesis,Surface Activity,and Foam Ability

A series of novel Gemini surfactants C_n-pi-C_n with piperazine moiety as spacer was synthesized and characterized by IR, ¹H NMR, and mass spectra. Their surface activities were evaluated by surface tension, electrical conductivity, and steady-state fluorescence. The obtained results indicated that the synthesized Gemini surfactants exhibited lower critical micelle concentration (cmc) and surface tension (γ_cmc) compared with traditional surfactants. The steady-state fluorescence measurement and electrical conductivity were recorded to demonstrate the accuracy of cmc values. In addition, the micellization was evaluated using conductivity measurement in the temperature range of 298–308 K. The foamability and foam stability of these Gemini surfactants were also examined. In which, the Gemini surfactant with the shortest chain (C₁₂) showed the best foamability but the poorest foam stability. Hydrophile–lipophile balance and emulsifying ability were studied and a comparatively poor emulsifying ability displayed.     

Properties of Interfacial Layers in Multicomponent Systems Containing Gelatin

The review is devoted to the analysis of the effect of the addition of various surfactants on the composition, structure, and the properties of the interfacial adsorption layers (IALs) formed at equilibrium in the aqueous gelatin solution–hydrocarbon system. Associates of variable compositions that are determined by the component ratio and the concentration of added surfactant are formed due to the interaction between gelatin and surfactant. The formation of associates is equivalent to the modification of gelatin. The properties of the IALs of modified gelatins are discussed on the basis of our own results and published data on the interfacial tension, the mass accumulation of surface-active components at the interfaces during the IAL formation, the IAL rheological properties and the stability of emulsion films varied with the conditions of IAL formation (the nature of low-molecular-weight surfactant, component concentrations, pH of aqueous phase, and temperature). It was concluded that modified gelatins can be considered as new surfactants governing the dynamics of the formation and fracture mechanism of the IALs and the stability of emulsion films. The properties of the IALs of modified gelatins are compared with those of IALs formed by gelatin and low-molecular-weight surfactants under the conditions when associates are formed directly at the interface due to the use of oil-soluble surfactants.     

新型脲基双子表面活性剂的合成及其性能

以N,N-二甲基-1,3-丙二胺、固体光气、溴代烷为原料合成了三种新型含脲基双子表面活性剂(LY-12、LY-14、LY-16),并通过1H NMR、ESI-MS和FT-IR表征了结构。测定了其Krafft点、乳化性能、起泡性能;通过测定表面张力γcmc以及不同温度下的临界胶束浓度(CMC)计算表面活性参数(Γmax、Amin、pc20)与热力学参数(ΔGmθ、ΔHmθ、ΔSmθ)。结果表明,LY-12、LY-14的Krafft点低于0℃,LY-16的Krafft点低于10℃;LY-12、LY-14、LY-16的乳化时间分别为173、275和338 s;LY-12的起泡性显著优于LY-14和LY-16;三种表面活性剂的表面张力γcmc分别为38. 77、37. 42和36. 59 m N/m;298. 15K条件下,其CMC值分别为0. 19、0. 15、0. 13 mmol/L。表面活性参数与热力学参数计算表明,三种表面活性剂均具有高的表面活性且胶束的形成是熵驱动的自发放热过程。     

Gemini型磺基琥珀酸酯钠表面活性剂的结构与性能的关系

以不同的醇为原料,合成了不同的Gemini型磺基琥珀酸酯钠阴离子表面活性剂,对它们的表面化学性能和应用性能进行了测定,并将其性质与其结构的关系进行关联。结果表明:其活性高于相应单基表面活性剂,且联结基、憎水链长度对其活性有影响。联结基长度增加,产物的临界胶束浓度(CMC)降低,对应的表面张力增加,其乳化性、起泡性、稳泡性、渗透力降低,增溶性提高;憎水链长度增加,CMC降低,对应的表面张力先减后增,其乳化性、稳泡性、增溶性提高,起泡性先增后减,渗透力减弱。     

PREPARATION AND SURFACE PROPERTIES OF NEW SULFOSUCCINIC DERIVATIVES OF FATTY POLYGLYCEROL ESTERS

ABSTRACT

The purpose of this work was to prepare hydrophilic anionic derivatives of polyglycerol esters in order to obtain new surfactants, characterized by the cosmetologic compatibility of renewable raw materials and the mildness of the chosen target surfactants. The derivatization has been done by esterification between polyglycerol esters (PGE) and maleic anhydride (MA) followed by sulfonation at the double bond, by sodium sulfite, getting sulfosuccinic derivatives. Polyglycerol esters composed of fatty acids of C₁₂ to C₁₆ and polyglycerol with chain length of n=l?10 served as raw materials for a number of sulfosuccinates. The surface properties (cmc; surface excess concentration, γ; surface molecular area, A; effectiveness, π_cmc; efficiency, _pC₂₀ contact angle, θ; wetting time and foam performance) of the raw materials and their anionic derivatives have been measured. The relationships between the chemical structure and the surface properties of the new surfactants have been established. Higher π_cmc and better foaming performance but lower wetting power were obtained by increasing hydrophilic chain length, to n=6. Over this length an opposite trend was found. A linear relationship beween log cmc and hydrophobic chain length was determined. Optimization of surface properties was accomplished by optimizing maleation conditions.     

Interfacial Properties of Hydrophobically Modified Biomolecules: Fundamental Aspects and Applications

This review describes the interfacial behavior of biomolecules, which were converted to more hydrophobic derivatives by covalent attachment of hydrophobic chains. The molecules presented are proteins (glucose oxidase, immunoglobulin G, gelatin, ovalbumin) and polysaccharides (carboxymethylcellulose, pullulan). In general, it was found that such hydrophobically modified biomolecules have enhanced surface activity and ability to penetrate into phospholipid monolayers. In addition, it has been demonstrated, that such molecules can be used as efficient emulsifiers and foaming agents, and in unique biomedical application based on combining the surface activity and recognition ability.

     

Physicochemical properties of series of cardanol polyoxyethylene ether carboxylates with different ethoxylation unit at the interface

Series of cardanol polyoxyethylene ether carboxylates were synthesized with biomass cardanol as material to study their physicochemical properties at the interface. The surface tensions of the cardanol nonionic-anionic surfactants were measured at 25?°C and the thermodynamic parameters of adsorption were also calculated. The surface activity and thermodynamic properties of the cardanol nonionic-anionic surfactants were correlated to their chemical structures. With increasing of the number of the ethoxylation unit in the hydrophilic group, a decrease in adsorption efficiency and an increase in surface tension at critical micelle concentration and thermodynamic free energy of adsoption were observed and were attributed to a decrease in adsorption of the cardanol nonionic-anionic surfactants at the interface. Series of the cardanol nonionic-anionic surfactants have good wettability and foaming property. The foaming capacity and the foaming stability of the solution of the cardanol nonionic-anionic surfactants increase by decreasing in the ethoxylation unit and by increasing the double bond of the hydrophobic group. The physicochemical properties of the cardanol nonionic-anionic surfactants at the interface are correlated to the chemical structures of the investigated surfactants, and there is the synergy effect between the nonionic hydrophilic group and the anionic hydrophilic group at the interface.     

Synthesis and Performance of Double-Chain Quaternary Ammonium Salt Glucosamide Surfactants

A series of double-chain quaternary ammonium salt surfactants N-[N′[3-(gluconamide)] propyl-N′-alkyl]propyl-N,N-dimethyl-N-alkyl ammonium bromide (C_nDDGPB, where n represents a hydrocarbon chain length of 8, 10, 12, 14 and 16) were successfully synthesized from D (+)-glucose δ-lactone, N,N-dimethyldipropylenetriamine, and bromoalkane using a two-step method consisting of a proamine-ester reaction and postquaternization. Their surface activity, adsorption, and aggregation behavior in aqueous solution were investigated via measurements of dynamic/static surface tension, contact angle, dynamic light scattering, and transmission electron microscopy. An analysis of their application performance in terms of wettability, emulsifying properties, toxicity, and antibacterial properties was conducted. The results show that with increasing the carbon chain length of the C_nDDGPB surfactants, their critical micelle concentration (CMC) increased and the pC₂₀ and efficiency in the interface adsorption of the target product gradually decreased. Moreover, the influence of the hydrophobic carbon chain length on the surface of polytetrafluoroethylene (PTFE) was even greater for the wetting effect, reducing the contact angle to 32° within the length range of C8–C14. The results of the contact angle change and the wettability experiments proved that C₁₀DDGPB exhibited the best wettability. The liquid paraffin and soybean oil emulsification ability of C_nDDGPB showed an upward trend followed by a downward trend with the growth of the carbon chain, with C₁₂DDGPB exhibiting the best emulsification performance. The D_long/D_short ratio was far lower than 1, which indicates mixed-kinetic adsorption. The surfactants formed spherical micelles and showed a unique aggregation behavior in aqueous solution, which showed an increase–decrease–increase trend with the change in concentration. A cell toxicity and acute oral toxicity experiment showed that the C_nDDGPB surfactants were less toxic than the commonly used surfactant dodecyldimethylbenzyl ammonium chloride (1227). In addition, at a concentration of 150 ppm, C_nDDGPB exhibited the same bacteriostatic effect as 1227 at a concentration of 100 ppm. The results demonstrate that sugar-based amide cationic surfactants are promising as environmentally friendly disinfection products.     

Physicochemical properties of alcohol polyoxyethylene ether acetate/alkyl ethoxy polyglycoside surfactant mixtures

Alcohol polyoxyethylene ether acetates (AECs) containing 10 ethylene oxide (EO) groups and a fatty chain of C_16-18 mixed with alkyl ethoxy polyglycoside can incorporate the excellent properties compared to the individual surfactants, which can broaden the range of applications in daily chemical industry. The physicochemical properties of the mixed surfactant systems were investigated by surface tension, wetting, foaming, and emulsification measurements. The phase behavior of the mixed systems was also studied. Synergism was obtained in surface tension, wetting, and foaming ability.     

Synthesis of Amphoteric Surfactants via Esterification Process

This article describes the synthesis of a novel amphoteric surfactant through esterification of 2‐hydroxy‐N,N,N‐trimethylethanaminium chloride with maleic acid alkyl ester of C₈, C₁₀, and C₁₂ chain length in the presence of base. Maleic acid alkyl esters were synthesized by the reaction of maleic anhydride with alkyl alcohol. Surface‐active properties were studied by different techniques such as surface tension and foaming property. Critical micelle concentrations (CMCs) were found by using surface tension values to learn the effect of chain length on CMC of synthesized surfactants. The best result obtained has minimal coproducts, an environmentally safer route, and a very good CMC value of surfactants.     

The influence of surfactants on the structure of transparent gelatin films

The interference image of cold-dried transparent gelatin films containing different surfactants was determined in the conoscopic ray of monochromatic light. From the results obtained the order of the structure of gelatin in the film was characterized. Unlike the ionic surfactants (sodium dodecyl sulfate and hexadecyltrimethyl ammonium bromide), which lead to a reduction of the ordered structure, the addition of nonionic and amphoteric surfactants [ethoxylized octylphenole and a technical C₁₂/C₁₄-dipoly(oxyethylene)ammoniopropane sulfonate] causes an increase of the ordered structure of gelatin. The results quantitatively agree with those found for the influence of surfactants on the secondary structure of gelatin in diluted gelatin solutions. The influence is independent of the gelatin/surfactant ratio and has been explained by gelatin/gelatin interaction competing with the gelatin/surfactant interaction if the gelatin concentration becomes sufficiently high.     

不同类型的明胶对DCG全息图的衍射效率影响的研究

本文对几种不同类型的明胶对DCG全息图的衍射效率的影响进行了研究。发现不同类型的明胶对DCG全息图的衍射效率的影响差异较大。活性胶,最高衍射效率可达80%以上,全息图的透明度很好;改性胶,衍射效率在60～80%之间,全息图上易产生“白雾”;惰性明胶,虽可得到透明清晰的全息图,但最高衍射效率一般不超过50%.     

Surface-active properties of a series of 1,1-dimethyl-1-alkylhydrazinium chlorides

The surface-active properties of a series of 1,1-dimethyl-1-alkylhydrazinium chlorides with C₁₀–C₁₈ in length were studied in comparison with Neonol AF 9–12 and Oksifos B surfactants. The limiting wetting angle, detergent and solubilization power, and foaming kinetics of these surfactants were studied in relation to the concentration of formation of monomolecular layer and type of the resulting micellar structures.     

Synthesis and Properties of Novel Cationic Triazolium Gemini Surfactants

New type of triazolium Gemini surfactants were synthesized by reaction of epichlorohydrine with long-chain fatty alcohols namely cetyl alcohol and oleyl alcohol furnishing product 2-(alkoxymethyl)oxirane followed by the their subsequent treatment with triazole resulting in the formation of 1-(1,2,4-triazole)-3-alokoxypropane-2-ol which on reaction with 1,6-dibromohexane resulted in the formation of triazolium-based cationic Gemini surfactant. Their formation was confirmed by IR spectroscopy. Surface tension values were used to determine the critical micelle concentration (CMC), minimum area per molecule (A_min) at air?water interface, Gibbs free energy of adsorption (ΔG_ads), the maximum surface excess concentration (Γ_max), and other parameters. The inhibition behavior of dimeric surfactant on the corrosion of carbon steel (CS) in 1 N H₂SO₄ aqueous medium was studied at 30°C. Performance tests like dispersion capability, foaming power and stability, emulsifying power, and wetting ability were determined. The obtained results show that dispersion capability, foaming power, foaming stability, and emulsifying ability are very good. The wetting power of synthesized surfactants is quite better.