Polyether-modified silicones

Flow injection analysis (FIA) ESI-MS and APCI-MS spectra for an EO/PO polyether modified silicone surfactant (PEMS) used as a personal care product have been obtained in positive and negative ionisation modes with the positive ionisation mode yielding the best results [41]. The spectra obtained in both modes were highly complicated, and thus no assignment was given. Significant differences in the ionisation results were obtained from the two interfaces, with those ions observed in the ESI-MS spectrum appearing in the lower... 

Scheme 2. Synthesis of carbohydrate- and polyether-modified silicones.

Physicochemical Properties of Carbohydrate- and/or Polyether-Modified Silicones... 

The following parameters of three different compounds (a polyether-modified silicone, a silicone with mixed substituents and a carbohydrate-modified silicone) were investigated and compared solubility in water, cloud point [4], reduction of surface tension in water (Table 1) and the viscosity as function of the shear rate in bulk (Fig. 1). 

Property Polyether-modified silicone Polyether-and carbohydrate -modified silicone (1 1) Carbohydrate-modified silicone... 

Table 1 shows that all three compounds have excellent solubility in water. A cloud point is only observed for the pure polyether-modified silicone at 83°C. The ability to reduce the surface tension of water is excellent for the polyether-modified silicone (28.9 mN/m), moderate for the silicone... 

The viscosities of the three compounds are approximately on the same level over the whole detection range. Only a slight decrease in viscosity is observed when the shear rate (Fig. 1) is increased all three compounds exhibit no shear thinning behavior [5]. In contrast, the viscosity levels are quite different. Whereas the carbohydrate-modified silicone exhibits a high viscosity (100 Pa s) the viscosity of the polyether-modified silicone is much lower (1.8 Pa s). The value observed for the silicone with mixed substituents is in between (50 Pa s). 

The observed effects are in accordance with molecular modeling experiments. As can be seen from semiempirical calculations in vacuo (PM3) the silicone backbone of the carbohydrate-modified silicone is strongly deformed and twisted because of attractive interactions between the carbohydrate moieties. In contrast, the silicone backbone of polyether-modified silicone is not distorted (Fig. 2). 

A cholesterol- and polyether-modified silicone was used for the stabilization of a W/0 emulsion. The same W/O emulsion was made using one of our well established W/O emulsifiers and the two emulsions were compared. To our surprise the cholesterol-modified emulsifier was as efficient as our standard product, which was the result of an extensive optimization procedure. Parameters that are generally used to characterize emulsions are ease of preparation, dispersity and long-term as... 

Ink compositions may also contain a slipping agent as a kind of surfactant in order to give excellent scratch resistance to the cured ink (51). Examples of slipping agents include polyester modified silicone or polyether modified silicone as silicone-based surfactant. Such compoxmds are fabricated by BYK-Chemie GmbH. 

Silicone-based materials are an important class of polymeric surfactants that are commonly used in the cosmetic industry. They consist of poly(dimethyl siloxane) (PDMS) that is modified by incorporation of specific groups for special applications. For example, dimethicone copolyol (used as emulsifier or dispersant) is typically a copolymer of PDMS and polyoxyalkylene ether. Aminofunctional silicones provide excellent hair-conditioning benefit. Polyether-modified silicones, including terpolymers containing an alkyl or polyglucoside moiety, are very effective emulsifiers for water-silicone emulsions. These silicone surfactants act as defoamers, depending on the amount and type of glycol modification. They are also used to reduce skin irritation. 

Akaishi, T. Eyebrow cosmetics containing polyether-modified silicones, and their applicators. Jpn. Kokai... 

Chem. Descrip. Polyether modified silicone wax Uses Surfactant, wetting agent, leveling agent, lubricant for paints and textiles conditioner, foaming agent in hair care, skin care, shampoos, body washes pro-... 

Chem. Descrip. Polyether-modified silicone prod. 

Chem. Descrip. Polyether-modified silicone prod, in n-butyl alcohol Uses Slip agent, mar resist, aid, lubricant, and scratch resist, aid for coating and ink films for waterborne or solvent-borne formulations incl. wood and container coatings (acrylic, alkyd, epoxy, SBR, PU, PVAc), overprint varnishes and flexible pkg. inks food-pkg. adhesives, coatings, paper Regulatory FDA 21 CFR 175.105,175.300,176.170,176.180 Properties Lt. tan cl. vise, liq., butyl alcohol odor si. sol. in water sp.gr. 0.9 dens. 

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