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Migration from a multilayer plastic material intended for food contact showed that 2,4,7,9-tetramethyl-5-decyne-4,7-diol mixture (surfynol), used as a surfactant in the adhesive employed to build the multilayer, was transferred to water and other food simulants in contact with the plastic. When these multilayer plastics were used for containing seminal doses for artificial insemination, it was found that fertility was seriously damaged in terms of motility, acrosome integrity, mitochondrial activity and penetration capacity in the cells, thus affecting male fertility. Quantitative proteomic analysis of exposed germinal cells demonstrated the inhibition of key proteins involved in the fertilization capacity by affecting the cytoskeleton, sperm motility, the energy machinery and sperm defense mechanisms against oxidation, therefore confirming the surfactant-induced male infertility. These results open up new and interesting perspectives for the study of reprotoxicity caused by different chemicals common in our daily lives. Significance This paper demonstrates the toxicity for reproduction of a common surfactant used in food packaging and the scientific reasons why the sperm loses reproductive capacity in presence of this chemical. So, the surfactant affects the male fertility. The surfactant is present in many adhesives used either for building multilayer materials or to glue paper and plastic in food packaging. This is the first time that reprotoxicity is demonstrated for this compound. According to the theoretical approach Threshold of Toxicological Concern (TTC) the compound is highly toxic but experimental data did not exist so far. The study described in this paper and the results obtained open a door to further research in which male infertility caused by chemicals could be demonstrated. [ABSTRACT FROM AUTHOR]

A series of polymeric surfactants, poly acrylic acid rosin polyethylene glycol esters (P-AAR-PEG), have been synthesized from natural diterpenic rosin. Their structures were characterized by Fourier Transform Infrared Spectrometer (FTIR) and their molecular weights were characterized by Gel Permeation Chromatography (GPC). Their critical micelle concentration (CMC), surface tension (γ CMC ), foaming property (FP), and hydrophile-lipophile balance (HLB) value were evaluated. Their thermal properties were measured by Thermal Gravimetric Analyzer (TGA) and fluid behaviors were studied by Rotational Rheometer. The influence of concentration on the properties of oil-in-water emulsions was examined and contrasted the stability of emulsion by the mean droplet size between day1 and day7. The weight-average molecular weight of P-AAR-PEG ranged from 1770 to 5071. CMC values of P-AAR-PEG were ranged from 0.33 to 0.87 g/L and the corresponding γ CMC values were ranged from 37.8 to 39.1 mN/m respectively. Their CMC and γ CMC values decreased and then increased with the increment of molecular weight of hydrophile group. Rheological measurements indicated that the P-AAR-PEG solutions changed from pseudoplastic property to Newtonian with increasing shear rate. P-AAR-PEG1000 had good emulsion ability to turpentine in water. When the concentration of P-AAR-PEG1000 was 8 wt%, the emulsion remained stable for more than 7 days. [ABSTRACT FROM AUTHOR]

Dietzia sp. A14101 isolated from an oil reservoir model column was found to induce a strong decrease of the interfacial tension (IFT) in hydrocarbon-water mixtures in the presence of the intact bacterial cells (Kowalewski et al., 2005). The strain was shown to be able to degrade a wide range of hydrocarbon substrates (Bødtker et al., 2009). Further studies showed that the surface-active compounds tentatively identified as glycolipids were produced by Dietzia sp. A14101 on non- and water-immiscibl e –hydrocarbon substrates, Part I (Hvidsten et al., 2017). The results suggested that biosurfactant (BS) was a mixture of several isomers. The study presented here is aimed to investigate whether BS are secreted into the aqueous medium, and if so, then at which phase of the culture growth and in which amounts – the dynamics of the BS release in incubations on water-immiscible hydrocarbons. Two methods of BS extraction from the medium were attempted and compared: a liquid–liquid extraction (LLE) and precipitation by acid. For qualitative and semi-quantitative assessment, gas chromatography-mass spectrometry (GC/MS), thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC–MS), surface tension measurements (SFT), emulsification (E 24 ) and oil-spreading tests were employed. The results indicated that BS only partially were secreted into the medium. Detectable amounts of glycolipids in media were first identified during the exponential growth phase. However, only a slight decrease of SFT was observed in the cell-free medium. The emulsification index values of the sampled material were lower than those reported for related strains. The results suggested that most of the BS produced by Dietzia sp. A14101 remains cell-bound during the culture development in a batch mode and only a narrow range of the BS isomers can be detected in small amounts in media. [ABSTRACT FROM AUTHOR]

Effect of the alkyl chain and head-group of surfactant (monoisopropylolalkyl amines and diisopropylolalkyl amines) on its interaction with polymethacrylic acid in aqueous solution has been studied by surface tension, electrical conductivity and viscometric measurements. From the surface tension studies, the critical aggregation concentration and critical micelle concentration were determined. Depending on the nature of head-group and polymer concentration, the polymethacrylic acid-surfactant interaction and the character of variation of the colloidal-chemical parameters of the complexes were studied. Petroleum-collecting capacity of the obtained complexes has been estimated in the waters of various mineralization degrees. [ABSTRACT FROM AUTHOR]

To optimize a benchmark commercial dishwashing formulation, this paper presents a fractional factorial design procedure coupled with a mixture design in order to obtain a formulation with better properties and cost, as well as to provide an example of quick formula optimization that may also be useful for other cleaning and personal hygiene sectors. First, a fractional factorial design was performed to determine the significant effects for each response variable: viscosity, performance, foaming, and Krafft temperature. Then, a mixture design was used to determine the compositions that feature the best results for each property of interest. The determined compositions that meet the requirements with 90-95% confidence showed that improvements in the compositions can be adopted. It was possible to estimate compositions based on commercial formulations that meet the same cost per kilogram of product but with gains in detergency, foaming, and viscosity volume. [ABSTRACT FROM AUTHOR]

The dilational rheological properties of hydrophobically modified polyacrylamide (HMPAM) or hydrolyzed polyacrylamide (HPAM) solutions without and with imidazolium surfactants ([C-4-Cim]Br and [Cmim]Br) at the air/water surface were investigated using oscillating bubble measurements. The results obtained suggest that imidazolium surfactants interact with the polymer on the surface, enhancing the dilational viscoelasticity of surface film. The dilational modulus value of [C-4-Cim]Br/HMPAM is higher than that of the [Cmim]Br/HMPAM system at low polymer concentration, confirming that [C-4-Cim]Br with two head groups and two hydrophobic chains can combine with a polymer to form a strong film on the surface. Moreover, imidazolium surfactants have stronger hydrophobic interaction with HMPAM chains than those of HPAM, thus enhancing the surface film strength for a surfactant/HMPAM system. The surface interaction mechanism between polyacrylamide and imidazolium surfactant is proposed to result from the electrostatic interactions and the hydrophobic effect. [ABSTRACT FROM AUTHOR]

We have prepared a variety of polymer nanoparticles with surface properties that can be switched from charged to uncharged using only carbon dioxide and air as triggers. Our initial approach to designing these materials relied on using pre-made 'switchable surfactants' via emulsion polymerization. This approach is similar to that employed to make the majority of polymer latexes used in commercial applications. We then refined the process further to address a shortcoming of many emulsion polymers, that of surfactant migration due to the stabilizing species not being covalently bound, by developing variants of surfactant free processes for making carbon dioxide switchable polymer colloids: (1) using only a carbon dioxide switchable initiator; (2) using a carbon dioxide switchable comonomer which is copolymerized in situ to generate the stabilizing species; and (3) using living radical polymerization to prepare nanoparticles via a Polymerization Induced Self Assembly (PISA) process. In all of these cases, the stabilizing moieties are covalently bound to the particle surface. [ABSTRACT FROM AUTHOR]

The article looks at a study related to development and testing of a class of surfactants for chemical enhanced oil recovery (EOR). It states that Guerbet alkoxy carboxylate (GAC) surfactants shows required performance under harsh reservoir conditions by providing branched and large hydrophobes, alkoxylate groups flexibility, alkaline and nonalkaline environments stability.

In this paper, the magnetorheological (MR) and magnetoviscous properties of ferrofluid-based iron particle suspensions were investigated. The 2.1-µm mean size Fe particles were dispersed in high-concentration transformer oil-based ferrofluid, the iron particle volume fraction in the resulting nano-micro composite magnetorheological fluid samples varying from Φ = 5 to 40 %. The ferrofluid carrier has φ = 23 % solid volume fraction of magnetic nanoparticles stabilized with chemisorbed oleic acid monolayer and without any excess surfactant. In the absence of the field, the ferrofluid has a quasi-Newtonian behavior with a weak shear thinning tendency. The static yield stress shows an increase of about 3 orders of magnitude for an iron particle content of approx. Φ = 25 % ( Φ = 42.25 %), while above this value, a saturation tendency is observed. The dynamic yield stress (Bingham model) also increases with the magnetic induction and the particle volume fraction; however, the saturation of the MR effect is less pronounced. The relative viscosity change has a maximum at Φ = (10-15) % due to the accelerated increase of the effective viscosity of the composite for higher Fe content. Addition of micrometer-sized iron particles to a concentrated ferrofluid without any supplementary stabilizing agent proved to be a direct and simple way to control the magnetorheological and magnetoviscous behavior, as well as the saturation magnetization of the resulting nano-micro composite fluid to fulfill the requirements of their use in various MR control and rotating seal devices. [ABSTRACT FROM AUTHOR]

The present study reports the effect of surfactants (rhamnolipids and triton X-100) on biodegradation of atrazine herbicide by strain A6, belonging to the genus Acinetobacter. The strain A6 was able to degrade nearly 80 % of the 250-ppm atrazine after 6 days of growth. The bacterium degraded atrazine by de-alkylation process. Bacterial cell surface hydrophobicity as well as atrazine solubility increased in the presence of surfactant. However, addition of surfactant to the mineral salt media reduced the rate and extent of atrazine degradation by decreasing the bioavailability of herbicide. On the contrary, addition of surfactant to atrazine-contaminated soil increased the rate and extent of biodegradation by increasing the bioavailability of herbicide. As compared to triton X-100, rhamnolipids were more efficient in enhancing microbial degradation of atrazine as a significant amount of atrazine was removed from the soil by rhamnolipids. Surfactants added for the purpose of hastening microbial degradation may have an unintended inhibitory effect on herbicide degradation depending upon contiguous condition, thus highlighting the fact that surfactant must be judiciously used in bioremediation of herbicides. [ABSTRACT FROM AUTHOR]