Dimethyl-polysiloxane

Syltheiin XLT (Dow Corning Coiporation). A sihcone polymer (Dimethyl Polysiloxane) recommended temperature range —70°C to 250°C odorless low in acute oral toxicity noncorrosive toward metals and alloys commonly found in heat transfer systems,... 

Chemical Name Dimethyl polysiloxane Common Name —... 

Anti-foaming Agent 900 Dimethyl polysiloxane 1.5 25th p 18 648, p 31, 1980... 

Antiflatidents (carminatives) serve to alleviate meteorism (excessive accumulation of gas in the gastrointestinal tract). Aborad propulsion of intestinal contents is impeded when the latter are mixed with gas bubbles. Defoaming agents, such as dimethicone (dimethyl-polysiloxane) and simethicone, in combination with charcoal, are given orally to promote separation of gaseous and semisolid contents. 

Programmed temperature (120 -200°C) chiral separation on a 0.25-mm x 25-m open tubular column with a 0.25-nm-thick stationary phase containing 10 wt% fully methylated p-cyclodextrin chemically bonded to dimethyl polysiloxane. [From W. Vetter and W. Jun, Elucidation of a Polychlorinated Bipyrrole Structure Using Enantioselective GC," Anal. Chem. 3002, 74,4287.]... 

Several graft copolymerizations were described by Ballantine (17, 64), Henglein (104, 105) and coworkers. Different monomer-polymer systems were examined styrene on polymethyl methacrylate, poly-2, 5-dichlorostyrene, polytetrafluoroethylene, polyethylene, polypropylene and polyisobutylene, acrylonitrile on polyethylene, rubber, polymethyl methacrylate and dimethyl polysiloxane, vinylpyrrolidone and acroleine on polymethyl methacrylate. The results agree with the preceding ones moreover they show the influence of the swelling and diffusion of the monomer into the polymer. 

FIGURE 6.2 Height equivalent to a theoretical plate (H) of a GC-separated compound versus average carrier gas velocity for a 3-m-long silicon channel coated with non-polar dimethyl polysiloxane stationary phase (a) native silicon surface (b) oxidized silicon surface. Plots A are for hydrogen carrier gas, and plots B are for air carrier gas [598]. Reprinted with permission from the American Chemical Society. 

Structural Formula Dimethyl polysiloxane Chemical Abstracts Registry No. 8050-81-5... 

For a nonpolar column (or equivalent) methyl silicone gum, or equivalent (preferably a bonded and cross-linked dimethyl polysiloxane) ... 

Syltherm 800 (Dow Corning Corporation). A silicone polymer (Dimethyl Polysiloxane) recommended temperature range -40°C to 400°C similar to Syltherm XLT, more appropriate for somewhat higher temperatures flash point is 160°C. 

Gas Chromatography. A Hewlett-Packard 5890 gas Chromatograph (Hewlett-Packard, Avondale, PA) with a flame ionization detector (FID), equipped with a 60 m X 0.32 mm I.d. DB-WAX column (df > 0.25 pm, bonded polyethylene glycol, J W Scientific, Folsom, CA) was employed. Helium carrier gas was used at a flow rate of 1.64 mL/min (30 C). The oven temperature was programmed from 30 C (4 min isothermaQ to 180 C at 2 C/min. A spirt ratio of 128 was used. The injector and detector were maintained at 200 C and 220 C, respectively. A 60 m X 0.32 mm i.d. DB-1 column (df - 0.25 pm, bonded dimethyl polysiloxane, J W Scientific, Folsom, CA) was used to anal e the sample prepared by vacuum steam distillation-extraction. Helium carrier gas was used a t a flow rate of 1.60 mL/min (30 C). The oven temperature was programmed from 30 C (4 min isothermal) to... 

INTEX EMULSION 195 is an aqueous emulsion of a dimethyl polysiloxane. It is a milky-white emulsion, infinitely dilutable with water. When diluting to the desired application level, slight paddle stirring is sufficient to effect complete dispersion of the concentrated emulsion. 

Antifoaming agents Dimethyl polysiloxane, singly or with silicon dioxide... 

Specifications. 40 ib (18.2 kg) gas fryers, frying temperature 350°F (177°C) hourly rotation breaded chicken, fish, onion rings, French fries 5-ppm dimethyl polysiloxane antifoam, 200-ppm tertiary butyi hydroguinone. FFA = free fatty acids, FOS = food oil sensor LY = Lovibond yellow LR = Lovibond red TPM = total polar material. 

Ballantyne DL Jr, Rees TD, Seidman I. Silicone fluid response to massive subcutaneous injections of dimethyl-polysiloxane fluid in animals. Plast Reconstr Surg 1965 36(3) 330-8. 

PDMS is being used as medicine (up to 15 g/day by oral intake) for digestive tract ailments and as direct food additives. The use of dimethyl polysiloxane is permitted in jams, jellies, marmalade, pineapple juice, and chewing gum up to 10 mg/kg under the E900 number. PDMS is extensively used in cosmetics, for example, in hand creams. Studies have confirmed that PDMSs have low toxicity. 

The most widely used surfactants are copolymers based on dimethyl polysiloxane and polysiloxanes. Some of these silicones are prepared with ethylene and propylene oxides. Some silicones contain Si-... 

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