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The main objective of this study was to design a sustainable lip gloss from water-in-oil emulsions by understanding the rheology of combining biosurfactants (rhamnolipids and sophorolipids) with silica particles (Aerosil powders). The different parameters consisted of the silica particle diameter size, the concentration of the particles within the formulation, alongside the different types of biosurfactant and oils used. The experimental results could provide information on the formulation design of cosmetic emulsions such as lip products and foundations.One parameter was varied each time, while the rest were kept constant in order to determine their effect on the viscosity profile of the formulations. A traditional mechanical rheometer was used in order to measure the bulk viscosity profiles of the different formulations, over a wide range of shear stress applied.The larger silica particle diameter size indicated an increase in the viscosity of the formulations, as yield stress was also generated for the specific diameter of 14 nm. It was also found that as the particle concentration increased, the viscosity increased as well. Rhamnolipids and sophorolipids indicated very similar behaviour, meaning that the biosurfactant acts as an emulsifier and does not impact the system's rheological behaviour. The replacement of silicone oil with other natural oils was only successful with canola, and castor oil, since jojoba, squalene and mineral oil were not stabilized.The lip gloss was designed by water-in-oil emulsions which were stabilized by biosurfactants and the rheology of the oil phase was enhanced by silica particles. The formulation rheology gave a stable emulsion, the shear-thinning effect ensured easy applicability, whereas the viscosity and elasticity provided nice hold on the lips.L'objectif principal de cette étude était de concevoir un brillant à lèvres durable à partir d'émulsions eau-dans-huile en comprenant la rhéologie de la combinaison de biosurfactants (rhamnolipides et sophorolipides) avec des particules de silice (poudres Aerosil). Les différents paramètres comprenaient la taille du diamètre des particules de silice, la concentration des particules dans la formulation, ainsi que les différents types de biosurfactants et d'huiles utilisés. Les résultats expérimentaux pourraient fournir des informations sur la conception de la formulation d'émulsions cosmétiques telles que les produits pour les lèvres, les fonds de teint, etc. MÉTHODES: Un paramètre a été modifié à chaque fois, tandis que les autres ont été maintenus constants afin de déterminer leur effet sur le profil de viscosité des formulations. Un rhéomètre mécanique traditionnel a été utilisé afin de mesurer les profils de viscosité en vrac des différentes formulations, sur une large gamme de contraintes de cisaillement appliquées. RÉSULTATS: La plus grande taille de diamètre des particules de silice a provoqué une augmentation de la viscosité des formulations, car une limite élastique a également été générée pour le diamètre spécifique de 14 nm. Il a également été constaté que lorsque la concentration des particules augmentait, la viscosité augmentait également. Les rhamnolipides et les sophorolipides ont montré un comportement très similaire, ce qui signifie que le biosurfactant agit comme un émulsifiant et n'a pas d'impact sur le comportement rhéologique du système. Le remplacement de l'huile de silicone par d'autres huiles naturelles n'a réussi qu'avec le canola et l'huile de ricin, car le jojoba, le squalène et l'huile minérale n'étaient pas stabilisés.Le brillant à lèvres a été conçu par des émulsions eau dans l'huile qui ont été stabilisées par des biosurfactants et la rhéologie de la phase huileuse a été améliorée par des particules de silice. La rhéologie de la formulation a donné une émulsion stable, l'effet d'amincissement par cisaillement a assuré une applicabilité facile, tandis que la viscosité et l'élasticité ont fourni une bonne tenue sur les lèvres.

Polysiloxane-based artificial skins are able to emulate the mechanical and barrier performance of human skin. However, they are usually fabricated in vitro, restricting their diverse applications on human body. Herein, we presented one-component waterborne cross-linkable polysiloxane coatings prepared from emulsified vinyl dimethicone, emulsified hydrogen dimethicone, and Karstedt catalyst capsules that were first synthesized by solvent evaporation method. The coating had good storage stability and meanwhile could form an elastic film quickly through merging of silicone oil droplets and subsequent hydrosilylation reaction. It was found that the mass ratio of vinyl dimethicone emulsion/hydrogen dimethicone emulsion (V/H), and the dosage of Karstedt catalyst capsules (K/(V + H)) were critical to the curing time, morphology, and mechanical properties of the coatings. With appropriate values of V/H and K/(V + H), the polysiloxane film had the mechanical performance comparable to that from solvent-based one. The coating could be topically applied to human skin in vivo and in situ turned into an elastic, invisible thin film with good water resistance. In contrast to those reported polysiloxane materials, the one-component waterborne polysiloxane coating was nontoxic and convenient for in vivo application on human body, making it be a promising candidate as artificial skin in the fields of cosmetics, medical treatment, and E-skin.

Multiphoton microscopy (MPM) excited at the 1700-nm window has enabled deep-tissue penetration in biological tissue, especially brain. MPM of skin may also benefit from this deep-penetration capability. Skin is a layered structure with varying refractive index (from 1.34 to 1.5). Consequently, proper immersion medium should be selected when imaging with high numerical aperture objective lens. To provide guidelines for immersion medium selection for skin MPM, here we demonstrate comparative experimental investigation of deep-skin MPM excited at 1600 nm in vivo, using both silicone oil and deuterium dioxide (D2 O) immersion. We specifically characterize imaging depths, signal levels and spatial resolution. Our results show that both immersion media give similar performance in imaging depth and spatial resolution, while signal levels are slightly better with silicone oil immersion. We also demonstrate that local injection of fluorescent beads into the skin is a viable technique for spatial resolution characterization in vivo.

Arylsilicones are widely exploited for their thermal and optical properties. The creation of phenylsilicone elastomers with specific physical properties is typically done by a "one-off" formulation and test process. Herein, it is demonstrated that high-throughput synthesis methods can be used to rapidly prepare a series of arylsilicone elastomers and then the relative impact of different aryl groups on their physical properties is assessed. Aromatic groups were incorporated into polydimethylsiloxane (PDMS) elastomers by exploiting the relative reactivity of different functional groups in the Piers-Rubinsztajn reaction. To analyze trends in the silicone mechanical properties as a function of increasing aryl concentration-structure/property relationships-libraries of elastomers were both quickly synthesized and characterized by using high-throughput suites starting from low viscosity silicone oils/monomers in 96-well plates. Liquid handling parameters were optimized to effectively work with the silicones. Incorporating aryl instead of alkyl crosslinkers into the PDMS backbone increased the silicone elastomer modulus by approximately 50 % (at a crosslink density of 6 %); elastomers prepared with an aromatic crosslinker with three contact points led to much higher moduli compared with those with one contact point at the same crosslink density. When located at precise rather than random points on the silicone chains, diphenylsilicones had lower moduli than analogous monophenylsilicones.

Purpose To identify an inexpensive, low-dielectric liquid for large magnetic resonance imaging (MRI) phantoms that can be used at multiple magnetic field strengths. Methods The T1 and T2 of four candidate phantom liquids (pure mineral oil, food-grade white mineral oil, silicone oil, and glycerol) with low dielectric constants were measured at three field strengths (0.35, 1.5, and 3 T) and extrapolated for 7 T. The complex permittivities of the liquids were measured for frequencies from 13 to 600 MHz. Proton densities were calculated based on molecular weight, proton number, and density. The results were compared to the American College of Radiology (ACR) large MRI phantom electrolyte liquid (10 mM NiCl2 and 75 mM NaCl in water) and deionized water. The liquids were evaluated based on the NEMA standards (T1 50 ms, proton density within 20% of water, and produces minimal dielectric artifacts). The radiofrequency (RF) wavelengths were computed for each liquid at the four field strengths to determine the risk of dielectric artifacts. Results The mineral oils were the only liquids to satisfy all of the NEMA guidelines. Excluding deionized water, silicone oil had the longest T1 and T2 , and was the most expensive liquid ($200/L). Glycerol had the shortest T1 and T2 , and the highest dielectric (excluding the ACR phantom electrolyte and deionized water). All of the liquids except silicone oil met the NEMA proton density guidelines. Conclusions Food-grade white mineral oil is a good candidate for use in a phantom due to its relaxation times, low dielectric, high proton density, and low cost. Glycerol and deionized water are poor choices for phantom liquids due to their relaxation times and high dielectric constants.

Purpose Episcleral eye plaques provide excellent local control of ocular melanoma, but vision sparing remains a significant problem with 30% or more of patients experiencing significant visual acuity degradation. The use of silicone oil shielding with Iodine-125 plaques has previously been reported to improve critical structure sparing. We hypothesized that the use of Palladium-103 would improve the shielding effectiveness of silicone oil due to the strong energy dependence of the photoelectric effect. This Monte Carlo simulation study reports a comparison of the shielding effects of silicone oil when used in conjunction with Pd-103 and with I-125 plaques. Materials and methods GEANT4 was used to simulate eye plaque treatments to an eye with either water-equivalent vitreous humor, or silicone oil in place of the vitreous humor. Two solid gold plaques, 15 and 23 mm, were simulated loaded with I-125 and with Pd-103 source seeds. Seed activity was normalized such that 85 Gy was delivered to the tumor apex in the water-equivalent cases. Tumor apex dose, central axis dose, and inner sclera dose reductions with silicone oil were evaluated. Results Silicone oil resulted in an underdosing to the tumor apex of 6.1% and 7.5% in the 15 mm plaque for I-125 and Pd-103, respectively, and 3.4% and 4.3% in the 23 mm plaque for I-125 and Pd-103, respectively. When renormalized to 85 Gy to the tumor apex in all scenarios, silicone oil reduced the dose to the inner sclera 90° from the plaque by 19-32% for the 15 and 23 mm plaques using I-125, and by 33-65% for the 15 and 23 mm plaques using Pd-103. Conclusions The combination of silicone oil and Pd-103 eye plaques offers the potential for greatly improved sparing to normal structures compared to Pd-103 plaques alone or I-125 plaques with or without silicone oil.

Nanoemulsions of silicone oil and pine oil using a binary surfactant system were prepared. Silicone oil and pine oil were used to achieve softness and mosquito repellency and antibacterial activity respectively when the nanoemulsion was applied on the fabric. A silicone surfactant (AG-pt) and a hydrocarbon surfactant (TDA-6) were used in different proportions to obtain stable nanoemulsions at the lowest possible droplet size. The various emulsification process variables such as ratio of hydrocarbon to silicone surfactant, surfactant concentration, ratio of silicone oil to pine oil, oil weight fraction and sonication time have been studied. The optimal variables include the ratio of hydrocarbon to silicone surfactant of 80:20, surfactant concentration of 8%, ratio of silicone oil to pine oil of 80:20, oil weight fraction of 20% and 15 min of sonication time at 40% of the applied power. Nanoemulsions were found to be very stable with emulsion droplet size around 41 nm. In order to compare different emulsification techniques, emulsions were also prepared using the conventional method. Emulsions analyzed using SEM showed spherical droplets ranging from 40 to 120 nm. Atomic force microscopy was used to evaluate the bounciness, fluffiness and softness of fabric. From this study, it was found that stable nanoemulsion with a lowest possible droplet size of silicone and pine oil could be prepared by ultrasonic emulsification technique in order to deliver multiple properties when applied to fabric.

A simple one-step method for the preparation of NaA zeolite spheres using a nonhydrothermal process is introduced in this article. The mechanism of formation of NaA zeolite spheres was studied by the suspension solidification method in both silicone oil and polyethylene glycol. The crystalline phase, micromorphology, and microstructure of the spheres produced were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET specific surface tests. The results demonstrate that geopolymer spheres can directly transform into NaA zeolite spheres in silicone oil but not in polyethylene glycol (PEG). Since the formation process in PEG cannot retain water in the geopolymer spheres, there is no additional medium that can transport and rearrange the aluminate and silicate groups in the geopolymer gel. Thus, the geopolymer gel cannot crystallize to form zeolite crystals.

Three-photon microscopy excited at the 1700-nm window (roughly covering 1600-1840 nm) is especially suitable for deep-brain imaging in living animals. To match the brain refractive index, D2 O has been exclusively used as the immersion medium. However, the hygroscopic property of D2 O leads to a decrease of transmittance of the excitation light and as a result a decrease in three-photon signals over time. Solutions such as replacing D2 O from time to time, wrapping both the objective lens and the immersion D2 O, and sealing D2 O with paraffin liquid have all been demonstrated, which add to the system complexity. Based on our recent characterization of immersion oils, we propose using silicone oil as a potential alternative to D2 O for deep-brain imaging. Excited at 1600 nm, our comparative deep-brain imaging using both D2 O and silicone oil immersion show that silicone oil immersion yields 17% higher three-photon signal in third-harmonic generation imaging within the white matter. Besides, silicone oil immersion also enables three-photon fluorescence imaging of vasculature up to 1460 μm (mechanical depth) into the mouse brain in vivo acquired at 2 seconds/frame. Together with the nonhygroscopic physical property, silicone oil is promising for long-span three-photon brain imaging excited at the 1700-nm window.

Destruction resistance such as start-up wear resistance characteristics of vitamin E (dl-α-tocopherol) blended ultra-high molecular weight polyethylene (UHMWPE) were evaluated using the destruction energy index (DEI). The DEI is used to evaluate wear-like destruction, by minimising the effects of viscosity at the sliding interface, and is estimated using newly designed friction testers. In this experiment, silicone oils of different viscosities were used to determine micro displacement up to a start-up point, and the DEI of the UHMWPE was changed from 17.48 to 1.84 μJ by adding vitamin E. The results suggest that the blending with vitamin E reduces destruction of UHMWPE at start-up friction in silicone oils.

Purpose Emulsification is related to complications arising from silicone oil (SO) tamponade. Currently, there is no widely accepted method for testing the propensity of SO to emulsify that are physiologically realistic and quantitative. Methods We compared different ways of inducing emulsification namely vortex mixing, sonication and homogenization. Silicone oil (SO) emulsification was quantitatively assessed using the Coulter counter and laser light scattering. The in vitro results are compared with the droplet size distribution profile of vitreous clinical washout. Conventional SO was compared with two novel SO blends with high-molecular-weight (HMW) additives (SOHMW2000 and SOHMW5000). Results Of the three methods for inducing emulsification, homogenization generated the most consistent emulsion samples with the smallest variance. The results from the Coulter counter measurement correlated strongly with the laser light scattering measurement within the range of 1 to 30 µm. The droplet size distribution profiles from human eyes were similar to that of emulsions generated in vitro by homogenization. The human size distribution profile was within the range of values obtained by the in vitro experiment. Compared to the conventional SO, the emulsion droplet counts for the new SO blends were significantly lower (SOHMW2000 and SOHMW5000 were 79% (±17%) and 49% (±18%) of the SO2000 and SO5000, respectively; p = 0.03 and p = 0.002). Conclusion Emulsion generated in vitro by homogenization has similar droplet size profile as human eyes filled with SO. Using this method to induce emulsion, SO blends with HMW additives demonstrated less propensity to emulsification with lower droplet counts compared to conventional SO with similar shear viscosity.

The destabilization process was investigated for a Janus emulsion of silicone and Bixa Orellana oils stabilized by polyoxyethylene sorbitan monooleate (Tw 80) and carboxymethyl cellulose. The emulsion stabilized with Tw 80 showed significant and fast creaming, a process that was prevented by the addition of the polymer. During the extensive coalescence of the emulsions stabilized by Tw 80, the Janus topology was retained for months of storage until, finally, separation of the oils occurred. This result strongly indicates an unexpected stabilizing action of the i nterfacial free energy. This conclusion was supported by a calculation for a realistic model system of the interfacial energy difference between two cases of coalescence. In the first case, the two coalescing Janus drops united into a larger Janus drop, while in the second case two drops formed, each with only one oil. The first case gave a spontaneous reaction (reduced interfacial energy), while the second one meant an increase of energy, i.e. it cannot happen without adding energy. The authors are aware that this stabilization is a new phenomenon in emulsion science with potential ramifications in future emulsion technology. However, it is essential to realize that the stabilization is of temporary occurrence in the destabilization process, and the free energy to give a final emulsion state with separated oils is overwhelmingly dominant. In short, Janus emulsions will, in the end, separate into layers of the liquids, like all emulsions.

Anisotropic slippery surfaces composed of directional, porous, conductive poly(3-hexylthiophene) (P3HT) fibers, and silicone oil exhibit excellent anisotropic sliding properties for several liquid droplets and the reversible control of conductive liquid droplets sliding on these surfaces under the application of voltage.

Dip coating is widely applied in industries for coating a solid substrate with a fluid because of its simplicity and applicability to substrates with different shapes. An experimental study was reported with dip coater on the film coating of solid plates by withdrawal from a tank filled with silicone oil fluids or polyacrylic acid (PAA) solutions with different rheological properties, the liquid film thickness deposited on the plate substrate was measured using capacitance method, and the evolution of free surface morphology was recorded with photographs. The purpose was to investigate the effects of plate substrate roughness, withdrawal speed, rest time, and fluid viscosity on the liquid film thickness and free surface morphology in detail. Results showed that the increases in coating fluid viscosity, withdrawal speed, and substrate roughness are beneficial to film thickening. The influence of rest time on liquid film thickness could be neglected when it was greater than 3 min. For silicone oil fluids, the free surface exhibited a depression, which gradually deepened, with the increasing in withdrawal speed and viscosities. By contrast, PAA solutions showed a bump on the free surface, exhibiting a curvature that increased with the increasing in withdrawal speed and concentrations. © 2016 Curtin University of Technology and John Wiley & Sons, Ltd.

The natural vitreous is a biological hydrogel consisting primarily of a collagen and anionic hyaluronate. It is surgically removed in many ocular diseases and replaced with fluids, gases, or silicone oils. We have been interested in developing synthetic hydrogels as vitreous substitutes. In this study, we combined the stiffness and hydrophobicity of polymethacrylamide (PMAM) and the anionic nature of polymethacrylate (PMAA) to make copolymers that would mimic the natural vitreous. We used bis-methacryloyl cystamine (BMAC) to introduce thiol groups for reversible crosslink. The Mn of copolymers ranged from ∼100 k to ∼200 k Da (polydisperisty index of 1.47-2.63) and their composition as determined by titration, 1 H NMR and disulfide test were close to the feed ratio. The reactivities of monomers were as follows: MAM > MAA ∼ BMAC. Copolymers with higher MAA contents gelled faster, swelled more, and had higher storage modulus (1.5 to 100 Pa) comparable to that of the natural vitreous. We evaluated the biocompatibility of copolymers by electric cell-substrate impedance sensing (ECIS) using human retinal pigment epithelial cells, primary porcine retinal pigmented epithelial cells, human microvascular endothelial cells adult dermis, and a fibroblast line 3T3. The biocompatibility decreases as the content of BMAC increases. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 977-988, 2017.

International audience; Simultaneous absorption of the acid gas CO2 and a volatile organic compound (VOC; here n-hexane) from a polluted gas stream by using an emulsion in a gas-liquid-liquid (GLL) reactor was investigated. In order to enhance the VOC capture, a nonaqueous liquid phase in the form of silicone oil was applied in the gas absorber. In addition, the regeneration process of both liquid phases was analyzed. The effect of methyldiethanolamine concentration in the aqueous phase and percentage of the organic phase was evaluated, showing opposite results for the liquid phases regarding each gas due to the differences between them. A higher amount of silicone oil causes a significant improvement in VOC absorption rate with negligible influence on CO2 behavior. The gas composition was modified by nitrogen

This study demonstrated for the first time the capability of methanotrophs to grow inside silicone oil (SO200) and identified the optimum cultivation conditions for enrichment of hydrophobic methanotrophs (high dilution rates (D) and low CH4 transfer rates). The potential of the hydrophobic methanotrophs enriched was assessed in a single-phase stirred tank reactor (1P-STR) and in a two-phase stirred tank reactor (2P-STR). Different operational conditions were systematically evaluated in both reactors (SO200 fractions of 30 and 60 %, stirring rates of 250 and 500 rpm, and D of 0.1-0.35 day(-1) with and without biomass retention). The results showed that the TPPB only supported a superior CH4 abatement performance compared to the 1P-STR (40% enhancement at 250 rpm and 25% enhancement at 500 rpm) at a D of 0.3 day(-1) due to the retention of the biocatalytic activity inside the SO200, while the 1P-STR achieved higher elimination capacities (EC up to ≈3 times) than the TPPB under the rest of conditions tested (ECmax = 91.1 g m(-3) h(-1) ). Furthermore, the microscopic examination and DGGE-sequencing of the communities showed that the presence of SO200 influenced the microbial population structure, impacting on bacterial biodiversity and favoring the growth of methanotrophs such as Methylosarcina. Biotechnol. Bioeng. 2016;113: 1203-1212. © 2015 Wiley Periodicals, Inc.

Materials that are able to withstand impact loadings by dissipating energy are crucial for a broad range of different applications, including personal protective applications. Shear-thickening fluids (STFs) are often used for this purpose, but their preparation is still limited, in part, to high production costs. It is demonstrated that polymeric surfactants comprised of linear telechelic sugar-modified silicones-with neither additives nor particles-generate transient polymer networks (TPNs) that represent a promising alternative to STFs. The reported polymers have distinct viscoelastic properties and can turn from a liquid into a rubbery network when force is applied. Saccharide-modified silicones with short chains (degree of polymerization (DP) ≈ 34, 68) are solids, but become energy-absorbing viscoelastic fluids when diluted in low-viscosity silicone oils; longer silicones (DP ≈ 338, 675) with low saccharide contents are viscoelastic fluids at room temperature. Excellent damping properties are found for the reported silicone surfactants, even those containing only 0.1% saccharides. The degree of energy absorption can be tailored simply by controlling the sugar/silicone ratio.

AIM Assessment of preactivated and thiolated silicone oils as potential long-term vitreous replacement. METHODS Thioglycolic acid (TGA) and 3-mercaptopropionic acid (MPA) were covalently coupled to amino-modified silicone oil and subsequently preactivated with 2-mercaptonicotinic acid (2-MNA). Each silicone thiomer was evaluated in view of oxidation, reductive reliquefaction, emulsification, and cytotoxicity. RESULTS Both thiol ligands were coupled in almost quantitative yield to the silicone oils' backbone with a total amount of thiol groups of 223 ± 25 and 219 ± 11 µmol/g for silicone-TGA and silicone-MPA, respectively. A following preactivation with 2-MNA of around 50% of all thiol groups could be achieved. Preactivated silicones showed a protection against oxidation as the viscosity of silicone-TGA and silicone-MPA after iodine treatment were two- and fourfold higher than the preactivated counterparts, respectively. The percentage of emulsification was below 8% for both preactivated silicones in comparison to control with 100% emulsification. Silicone-TGA-MNA and silicone-MPA-MNA could be aspired via a 20 G needle within 35 s and showed a reversible sol-gel transition. CONCLUSION Preactivated silicone oils tackle the shortcomings of currently available silicone oils as they unite suitable handling qualities with a resistance against emulsification, which renders them promising for long-term vitreous replacement. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2015. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 551-559, 2017.

Objective The purpose of this study was the evaluation of thiolated silicone oil as novel skin protectant exhibiting prolonged residence time, enhanced barrier function and reinforced occlusivity. Methods Two silicone conjugates were synthesized with mercaptopropionic acid (MPA) and thioglycolic acid (TGA) as thiol ligands. Adhesion, protection against artificial urine and water vapour permeability with both a Payne cup set-up and transepidermal water loss (TEWL) measurements on porcine skin were assessed. Results Silicone thiomers showed pronounced substantivity on skin with 22.1 ± 6.3% and 39.2 ± 6.7% remaining silicone after 8 h for silicone-TGA and silicone-MPA, respectively, whereas unmodified silicone oil and dimethicone were no longer detectable. In particular, silicone-MPA provided a protective shield against artificial urine penetration with less than 25% leakage within 6 h. An up to 2.5-fold improved water vapour impermeability for silicone-MPA in comparison with unmodified control was discovered with the Payne cup model. In addition, for silicone-MPA a reduced TEWL by two-thirds corresponding to non-thiolated control was determined for up to 8 h. Conclusion Thiolation of silicone oil leads to enhanced skin adhesiveness and barrier function, which is a major advantage compared to commonly used silicones and might thus be a promising treatment modality for various topical applications.

CE is one of the most important analytical techniques. Although the injected sample volume in CE is only in the nanoliter range, most commercial CE instruments need approximately 50 μL of the sample in the injection vial to perform the analysis. Hence, in order to fully profit from the low injection volumes, smaller vial volumes are required. Thus experiments were performed using silicone oil, which has higher density than water (1.09 g/mL) to replace sample dead volume in the vial. The results were compared to those performed without using the silicone oil in the sample vial. As an example five standard proteins namely beta-lactoglobulin, BSA, HSA, myoglobin, and ovalbumin, and one of the coagulation cascade involved proteins called vitonectin were investigated using CE. Mobility ratios and peak areas were compared. However, no significant changes were observed (RSDs% for mobility ratios and peak areas were better than 0.9 and 5.8%, respectively). Afterwards, an affinity CE method was used to investigate the interactions of two proteins, namely HSA and vitronectin, with three ligands namely enoxaparin sodium, unfractionated heparin, and pentosan polysulfate sodium. Mobility shift precision results showed that the employment of the filling has no noticeable effect on any of the protein-ligand interactions. Using a commercial PrinCE instrument and an autosampler the required sample volume is reduced down to 10 μL, and almost this complete volume can be subsequently injected during repeated experiments.

BACKGROUND : Four silicone oils (PolyDiMethylSiloxane, PDMS) of different viscosities, namely 5, 20, 50, and 100 mPa s were characterized to select the most suitable polymer for the biol. treatment of toluene. The PDMS volatilities and the partition coeffs. of toluene between air and PDMS were investigated. Toluene biodegrdn. tests were also carried out to assess the absence of toxicity of the considered PDMS vis-a-vis the microorganisms. RESULTS : PDMS 20, 50 and 100 had negligible volatilities at 25 °C and 35 °C, whereas PDMS 5 was volatile even at 25 °C. The results indicate that the amt. of VOCs emitted by PDMS increased with the temp. according to a logarithmic law. The partition coeff. of toluene between air and the four PDMS were similar (H = 2.9 Pa m3 mol-1) indicating that the affinity between toluene and PDMS was identical whatever their viscosity. Moreover, biodegrdn. tests allowed the conclusion that the four PDMS tested are not toxic for microorganisms. CONCLUSION : PDMS 20, 50 and 100 were suitable at 25 °C for the biol. treatment of toluene. Since all these PDMS were satisfactory at 25 °C, it could make sense to select the least viscous oil for use in the process, i.e. PDMS 20. © 2015 Society of Chem. Industry.

The apparent viscosities of foams generated by passing argon through silicone oil are measured. The foams are found to be non-Newtonian flows having apparent viscosities 4–5 times higher than the dynamic viscosity of the origin fluid. The movements of different particles and droplets and their residence times are studied. The measured average velocities of the particles/droplets are substantially lower than the values estimated based on the dynamic viscosities. For both mechanical and gas stirrings, the flows of the foam are very different from pure liquid. The movement of the bar and stirring gas bubbles only pushes a limited number of bubbles which are very close to them to move. No bulk flow as in pure liquid is generated by the stirring.

We performed chemical, mineralogical, and isotopic studies of the first interplanetary dust particles (IDPs) collected in the stratosphere without the use of silicone oil. The collection substrate, polyurethane foam, effectively traps impacting particles, but the lack of an embedding medium results in significant particle fragmentation. Two dust particles found on the collector exhibit the typical compositional and mineralogical properties of chondritic porous interplanetary dust particles (CP-IDPs). Hydrogen and nitrogen isotopic imaging revealed isotopic anomalies of typical magnitude and spatial variability observed in previous CP-IDP studies. Oxygen isotopic imaging shows that individual mineral grains and glass with embedded metal and sulfide (GEMS) grains are dominated by solar system materials. No systematic differences are observed in element abundance patterns of GEMS grains from the dry collection versus silicone oil-collected IDPs. This initial study establishes the validity of a new IDP collection substrate that avoids the use of silicone oil as a collection medium, removing the need for this problematic contaminant and the organic solvents necessary to remove it. Additional silicone oil-free collections of this type are needed to determine more accurate bulk element abundances of IDPs and to examine the indigenous soluble organic components of IDPs.

A process for making high-density polyethylene (HDPE) single-polymer composites (SPCs) by insert injection molding was investigated. HDPE SPCs with relatively good tensile and interfacial properties were prepared within a short cycle time within a temperature range of 40°C. Melt-spun HDPE fibers were made from the same resin as the matrix. The fibers were heat treated in silicone oil, with and without tension, to study the changes of fiber properties upon exposure to high temperature. HDPE SPCs containing about 30 wt% lab-made HDPE fabric achieved a tensile strength of 50 MPa, 2.8 times that of neat HDPE. The peel strength of HDPE SPCs increased with increasing injection temperature and achieved a maximum value of 16.7 N/cm. Optical micrographs of polished transverse cross-sections of the SPC samples showed that higher injection temperature is beneficial to the wetting and permeation properties of the matrix. Scanning electronic microscope photographs suggested good bonding and compatibility between the fibers and the matrix. POLYM. ENG. SCI., 55:2448–2456, 2015. © 2015 Society of Plastics Engineers

The introduction of surface vinyl groups to PDMS microspheres broadens the latter's applicability range since the microspheres can be further functionalized or crosslinked into elastomers. Quantification of the surface vinyl concentration of PDMS microspheres is therefore essential. Here, a novel titration method, which is based on efficiently and covalently bonding mono-functional hydride to vinyl, is employed to determine surface vinyl concentration. The titration method exhibits good reproducibility in detection, thereby underlining its potential applicability as a general titration method for cured silicones. Vinyl functional PDMS microspheres are mixed with a hydride crosslinker and non-reactive silicone oil to create a system which allows for extensive crosslinking. Both visual observations and rheological studies show that a robust macroscopic PDMS elastomer is obtained upon crosslinking. Furthermore, the influence of stoichiometric imbalance, and the weight fraction of silicone oil on the terminal storage modulus of the macroscopic PDMS elastomer, is investigated. The wide range of stoichiometries facilitating crosslinking between the PDMS microspheres and the hydride crosslinker found in this study is beneficial for delivering PDMS elastomer to hard-to-reach places, since the sensitivity of the system on concentration fluctuations is small.

Summary Appropriate surgical technique is the most important factor for the anatomical success in the management of retinal detachment (RD) with PVR. Retinectomies are frequently required in detached eyes complicated by severe PVR. Knowing when and how to perform a retinectomy is necessary for a vitreoretinal surgeon and this talk will cover important steps in this surgical maneuver. Silicone oil endotamponade is also frequently preferred in PVR surgery. How to handle silicone oil during injection and its removal is important to avoid its major complications. Pearls related to these steps as well as some important properties of silicone oils will be discussed in this talk.

Well-defined diblock copolymers of linear polyethylene (PE) and poly(dimethylsiloxane) (PDMS) have been synthesized through a facile route combining the thiol-ene click chemistry of vinyl-terminated polyethylene (PE-ene) and the sequential esterification reaction. The resulting diblock copolymers are characterized by 1H NMR, FT-IR, DSC, TGA, and TEM. In addition, the PE-b-PDMS diblock copolymers have been evaluated as compatibilizers in the blends of high-density polyethylene (HDPE) and silicone oil. The morphological analysis and mechanical properties demonstrate that the compatibilized blends with low loading concentration of PE-b-PDMS display significant improvements in modulus of elasticity and elongation at break as compared to the uncompatibilized binary blends. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 3205–3212

We describe the ultrasonic initiated modification of four types of oil; sunflower oil, transformer oil, cable oil and silicone oil. Ultrasound is effective in initiating and driving reactions of the three hydrocarbon oils but ineffective in the case of silicone oil. The hydrocarbon oils showed noticeable reductions in viscosity after sonication; this reduction can be enhanced by incorporating nucleating agents such as particulate carbon. The viscosity loss is not permanent without using stabilisers and with time the viscosity approaches its initial value. The ultrasonic reaction is thought to be free radical in nature, since incorporation of a radical scavenger before sonication prevents any viscosity loss, whereas incorporation after sonication stabilises the drop in viscosity. Oxygen is proposed to be involved since purging with nitrogen diminishes any viscosity drop observed, and selected ion flow tube MS analysis of volatiles from the oils after sonication indicates an increase in the number and quantity of oxidised products. Copyright © 2014 John Wiley & Sons, Ltd.

Omniphobic metallic surfaces obtained with a robust two-stage process are reported. The surfaces demonstrate high apparent contact angles accompanied with a low contact angle hysteresis for a variety of liquids, including water, diidomethane, canola, castor, silicone oils, and crude petroleum oil. The superoleophobicity was achieved by fluorination of the nano-rough aluminum surfaces under treatment with perfluorononanoic acid, as established by TOF-SIMS spectrometry. The stability of the Cassie wetting regime was investigated. The critical surface tension of a liquid corresponding to the onset of wetting transitions was established experimentally.

Processing convenience and formulation flexibility frequently require the delivery of the silicone oils as emulsions. The shelf life of the latter is achieved kinetically, in the most cases via the addition of surfactants. On the other hand, surfactants are the subject of increasing scrutiny with regard to their environmental impact. The goal of this study is to formulate silicone oils in surfactant-free emulsions and to demonstrate the controlled release of the active silicone material. A non-aqueous silicone emulsion comprising of a continuous phase of a polar organic liquid, having droplets of silicone antifoam compound dispersed therein, have been developed. These systems are stabilised by (fractal) waxy particles which play a dual role. They act as Pickering stabilisers and in the same time they form an elastic network in the continuous phase, providing a creaming stability of more than a year. A triggered release of the (antifoam) silicone active can be achieved via heating above the melting temperature of the waxy particles. This is demonstrated by the fact that no antifoam activity has been observed at temperatures below ca. 60°C, while at temperature of above 65–70°C a strong antifoam effect has been obtained.

This paper reports a non-catalyzed environmentally friendly method of synthesizing hyperbranched polymethylvinylborosiloxanes (PMVBSs) and their use to improve the thermal stability of normal addition-curable silicones (ACSs). PMVBSs were synthesized by the direct polycondensation of dimethoxymethylvinylsilane with boric acid at 80–130°C in 1,4-dioxane or diglyme. They were characterized by gel permeation chromatography; FT-IR; 1H, 13C, 29Si and 11B NMR; and TGA. PMVBSs were composed of Si―O―Si and Si―O―B bridges with some unreacted B―OH groups remaining, and had a ceramic yield up to 65.97% at 900°C. PMVBS-modified ACSs (PBS-ACSs) were prepared by curing the PMVBSs with hydrogen-containing silicone oil under Karstedt (platinum divinyltetramethyldisiloxane) catalysis. Thermal stability of PBS-ACSs was characterized by TGA in N2 or air, and ceramic yields as high as 76.7% were obtained. Gas decomposition during the ceramization of PBS-ACSs was examined by TG/mass spectroscopy. The SiBOC ceramics formed were characterized by FT-IR, Raman, 29Si and 11B magic angle spinning NMR and elemental analysis. This method provides a valuable way to improve the thermal stability of ACSs. Copyright © 2013 John Wiley & Sons, Ltd.

The aggregation behavior of silicone oil polymers exposed to Ar plasmas was investigated. A reptation aggregation related to the viscosity of silicone oil was found. The viscosity dependence η ∼ Lb on the reptation length L with b = 3.37 in the viscous coefficient range of 20 and 500 mm2 · s−1 was obtained. The formation of reptation aggregation is thought to relate to the gradient viscosity in the vertical direction due to crosslinking and formation of SiO network at the surfaces of silicone oils induced by energetic ions bombardment and the vacuum-ultraviolet irradiation, as well as the temperature gradient in vertical direction induced by energetic ions bombardment.

In this work, a novel melamine-formaldehyde-Fe3O4 foam was prepared from a mixture containing melamine-ethanolamine-formaldehyde resin, melamine-glycol-formaldehyde resin and carboxylated Fe3O4 nanoparticles by microwave foaming method. The two resins were characterized by 13C-NMR, respectively. The structures of foams, mechanical and fire-retardant properties were experimentally characterized separately by scanning electron microscopy, universal testing machine, limit oxygen index, thermogravimetry-differential thermal analysis, and Fourier transform infrared spectra. The effects of the resin viscosity, emulsifier, nucleating agent, curing agent, silicone oil, microwave heating time and blowing agent on the structure of foam were investigated. Results showed that the properties of foam were decided by not only the molecular structure but also structure of foam, and the carboxylated Fe3O4 nanoparticles can improve the toughness and flame retardant properties of magnetic foam obviously from both aspects. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2688–2697, 2013

Annular centrifugal contactors were developed as single, compact units utilized to transfer desired species between immiscible fluid phases. Critical to understanding the mass-transfer characteristics in the annular mixing region is a clear picture of the distribution of droplet sizes of the fluids involved. To date, very little experimental data appears in the literature. We fill that void by using laser fluorescence and optical methods to directly observe and measure drop-size distributions for a silicone oil/water system in a centrifugal contactor. The shape and characteristics of the log-normal distributions, including the Sauter mean diameter and distribution means, are elucidated in terms of rotor speed and organic phase fraction. The size distribution of entrained air bubbles is also examined. The results presented here will be invaluable in validating and expanding the predictive capacity of the many models that have been developed to describe the flow within these devices. Published 2013 American Institute of Chemical Engineers AIChE J, 59: 2219–2226, 2013

A fluorine-containing silicone resin substituent group,vinyl group, and inorganic framework (SR-FVI) was synthesized through hydrolytic condensation by using vinyltriethoxysilane, 13-fluorooctyltriethoxysilane, tetraethoxysilane, and tetramethyldivinyldisiloxane as monomers. A new cross-linked hybrid membrane (CHM) was prepared with the hydrogen-containing silicone oil (HSO) as a cross-linking agent, polydimethylsiloxane containing vinyl group and the SR-FVI as matrix materials to enhance its membrane-forming ability and permselectivity. The membrane-forming process and the cross-linking reactions between the silicon–hydrogen bond and the vinyl group were carried out simultaneously at room temperature. The effects of the SR-FVI content in the CHMs, pressure difference, and temperature on the oxygen-enriching properties were evaluated and discussed. A good equilibrium between membrane-forming ability and oxygen-enriching properties was attained, for example, oxygen permeability coefficient and ideal separation factor of the CHM with the SR-FVI content of 50 wt% at 20°C and 0.10 MPa were 594 Barrer and 3.50, respectively. Compared to cross-linked PDMS membranes without the SR-FVI, the CHMs show better gas selectivity and similar gas permeability. The oxygen-enriching property is attributed to the fluorine-containing component in the CHM due to its good oxygen solubility. POLYM. ENG. SCI., 53:2328–2335, 2013. © 2013 Society of Plastics Engineers

During the last decade the abrasive flow machining process became an accepted technique to smooth and to round inner edges in badly contactable regions of complex geometries, e.g. grooves in rails of common rail systems. The process is based on the flow of a highly viscous silicone oil which is charged by abrasive particles. This leads to an efficient rounding of the egdes. In the present article a material model for the non-Newtonian behaviour of the abrasive paste is proposed, the material parameters are identified according to experiments and, finally, a simulation of the abrasive flow machining process is presented based on a model implementation in the software package COMSOL Multiphysics®.

Background To evaluate and compare the perfluorocarbon liquid, silicone oil, and viscoelastic against standard saline, in their ability to dampen the impact force of a foreign body, dropped within the eye. In an experimental surgical model in where cohesive and adhesive forces of the substances are not enough to float heavy-than-water foreign bodies. Methods A model of ophthalmic surgery was constructed. A BB pellet was dropped from 24 mm onto a force transducer through four different fluids: balanced salt solution, perfluoro-n-octane, viscoelastic, and silicone oil. The impact energy (force) for each case was measured and recorded by the force transducer. The mean force of impact for each fluid was compared using the Student t-test. Results Silicone oil resulted in the lowest force of impact. Both silicone oil and viscoelastic dampened the impact an order of magnitude more than perfluoro-n-octane and balanced salt solution. Conclusions Silicone oil and viscoelastic cushioned the force from a dropped BB. They may be useful adjuncts to prevent iatrogenic retinal injury during vitrectomy for intraocular foreign body removal.