Polymethyl siloxane

Column Fused-silica capillary column size (50 M x 0.32 mm) coated with a 5-pm film of chemically-bonded polymethyl siloxane ... 

Activated dimethicone (activated polymethyl-siloxane) is a mixture of liquid dimethicones containing finely divided silica to enhance the defoaming properties of the silicone. The mechanism by which dispersion of colloidal silica antifoams improves their action is not well understood. 

Gas chromatography GC, employs a gaseous mobile phase, e.g. nitrogen or helium, and usually a liquid stationary phase, e.g. non-polar Apiezon (alkane grease), OVIOI (polymethyl siloxane) or polar PEG20M (polyethylene glycol). Separation is effected by competition between attraction of the components for the stationary phase and volatility at the column temperature being used, that is, retention forces versus partial vapour pressure in the mobile phase. 

Foams can occur in the intestines where they may cause indigestion, pain and/or a sense of being full, collectively known as dyspepsia [12]. Pharmaceuticals designed to combat dyspepsia usually contain antifoams, antacids and possibly enzymes [12]. The most common antifoams seem to be polymethyl-siloxanes (referred to as dimethicone in the pharmaceutical literature [12]) mixed with hydrophobic particles, such as hydrophobic silica. The formulation is delivered as a tablet, suspension or emulsion (simethicone tablets, simethicone oral suspensions, simethicone emulsions). Foams can also be used to administer drugs, such as in contraceptive foams. 

ACp which accompanies MW increase (and consequent Tg increase). The cases illustrated are PDMS (triangles), polycarbonate (filled circles) and polymethyl siloxane (open circles), (reproduced from ref.29, by permission)... 

Chem. Descrip. Polymethyl siloxane, methoxy-functional Uses Binder for highly pigmented paints, VOC-compliant coatings, heat-resist., anticorrosive paints containing aluminum powd. or zinc dust and heat-resist., pigmented matte finishes such as car exhaust paints food-contact coatings... 

Chem. Descrip. Modified polymethyl siloxane aq. emulsion Uses Water repellent for masonry, impregnation of facades (bricks, artificial limestone, nat. stone, plaster, etc.)... 

INVESTIGATION OF THE THERMOPHYSICAL PROPERTIES OF POLYMETHYL SILOXANE LIQUIDS. //ENGLISH TRANSLATION OF TEPLOENERGETIKA 17/2/ 80-3,1970.//... 

Kao, W.J., Zhao, Q.H., Hiltner, A. et al. (1994) Theoretical analysis of in vivo macrophage adhesion and foreign body giant cell formation on polymethyl-siloxane, low density polyethylene, and polyetherurethanes. J. Biomed. Mater. Res., 28 (1), 73-80 Recent article on macrophages on polymers and references some articles on oxidative events. 

Although it is possible to chemically bond polymethyl-siloxane polymers on fused silica capillary columns with film thicknesses up to 5 m (high capacity columns), these capillary columns provide a relatively low resolution. 

Acetoxypropyl-polymethyl-siloxane-copolymer Type Organophilic Chemical and Physical Properties ... 

Ainshtein and Shulyat eva have tabulated retention indices for alkylchlorosilanes and propylchlorosilanes on a polymethyl-siloxane liquid PMS-20,000 and on a fluorosiloxane liquid FS-303 mobile phases. 

In addition to epoxy resins, MA has been investigated as a crosslinker for a variety of polymers. For example, poly(oxycyclohexene), polyary-lates, hydroxy-substituted polyspiro resins,and polymethyl-siloxanes have been crosslinked with MA to give thermoplastic adhesives, heat-resistant polyarylates, electrical insulating materials, and other composites. 

Chem. Descrip. Alkyl modified polymethyl siloxane wax Uses Spreader/wetting agent... 

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