Silicone elastomers vinyl

Compared to dimethyl silicone elastomers, vinyl silicone elastomers have much reduced compression set. A further point is that although silicone elastomers are mostly reinforced with silica, special purpose electrically conducting elastomers are filled with carbon black. Carbon black does not inhibit cure by less active peroxides and may be used with vinyl silicone elastomers. This filler does, however, inhibit vulcanization by benzoyl peroxide (and its derivatives) and therefore cannot be added to dimethyl silicone gums. 

Flexible foams with oxygen index values of 40-53 were also prepared by the same authors from blends of copolymer IV and a silicone elastomer, (a phenyl vinyl polydimethylsiloxane) [592]. 

Some other silicon elastomers include vinyl silicone elastomers, phenyl silicon elastomers, nitrile silicone elastomers, and fluorosilicone elastomers. 

Silicone. Silicone elastomers have a siloxy backbone with methyl, vinyl, and phenyl groups attached. The elastomers are designated by their chemical composition, as follows methyl silicone (MQ), methyl vinyl silicone (VMQ), methyl phenyl silicone (PMQ), methyl phenyl vinyl silicone (PVMQ), and fluorovinyl methyl silicone (FVMQ). 

There are a large variety of elastomers based on a chain -Si-O-Si- with different groups attached to the Si atom, that affect the properties of the polymer. Technologically, the most widely used silicone elastomers are those with all methyls on the silicone atoms, i.e., polydimethylsiloxanes (PDMSs), or ones with less than 0.5 mol% of vinyl substitution for the methyls. Irradiation of PDMS produces hydrogen, methane, and ethane. The gas yield at room temperature correlates with the concentration of cross-links formed. This can be expected since double bonds cannot be formed. 

The linear silicone fluids consists of D units. Silicone elastomers and rubbers are composed of D units bearing as side-chain or end-chain cross-linkable functional groups (vinyl, silanol). Highly branched silicone resins combine T units and D units and in other cases Q and M units. In this way a very great variety of products with a broad application range is obtained. 

Insoluble inserts are polymeric systems into which the drug is incorporated as a solution or dispersion. Ophthalmic inserts (ocuserts) have been reported using alginate salts, poly(A-vinyl pyrrol-idone), modified collagen, and hydroxyl propyl methyl cellulose. Ocufit is a silicone elastomer-based matrix that allows for the controlled release of an active ingredient over a period of at least 2 weeks. Osmotically controlled inserts have also been described, where release is by diffusion and is osmotically controlled. 

CAS 21645-51-2 EINECS/ELINCS 244-492-7 Uses Smoke suppressant, flame retardant, filler for PVC and XLPE wire/ cable insulation, SBR compds., epoxies, silicones, elastomers, neoprene foam, vinyl sheet flooring, adhesives, coatings, paints, polishes Pn rerties Superfine powd. 3.5 p avg. particle diam. sp.gr. 2.42 surf, area 8 m /g oil absorp. 32 brightness (TAPPI) 95 ref. index 1.57 hardness (Mohs) 2.5-3.5... 

Uses Heat stabilizer for vinyl resins, lacquers, elastomers lubricant for flexible vinyls catalyst for PU foam and silicone elastomers catalyst forfood-contact PU resins and PU resins in food-pkg. adhesives plasticizer... 

PSE-780] PSE-785. See Silicone elastomer Pseudoacetic acid. See Propionic acid Pseudobutylbenzene. See t-Butylbenzene Pseudocapsaicin. See Nonanoyl 4-hydroxy-3-methoxybenzylamide Pseudocollagen . See Yeast extract Pseudocumene. See 1,2,4-Trimethylbenzene Pseudocumidine. See 2,4,5-Trimethylaniline Pseudocumol. See 1,2,4-Trimethylbenzene Pseudocyanuric acid. See Isocyanuric acid Pseudohexyl alcohol. See 2-Ethyl-1-butanol 3H-Pseudoindolium, 2-(2-(2,4-dimethoxyanilino) vinyl)-1,3,3-trimethyl chloride. See Basic yellow 11... 

Phenylmethyl/dimethylsiloxane copolymer base oil, lubricant jet engine synthetic PEG-3 dipelarqonate base oils, synthetic lubricant Diester oils Trimethylolpropane tripelargonate base polymer, addition cure silicone elastomers Polydimethylsiloxane, vinyl-terminated base polymer, two-component RTV fluids Dimethicone, vinyidimethyl-terminated base, acid resolution Dehydroabietylamine base, act. ingreds. 

C9-11 pareth-8 Diethyl sulfate Dilauryl phosphite Dimethylaminoethyl acrylate Dimethylaminopropylmethacrylamide 2,6-Dimethylmorpholine Dimethylolpropionic acid Formaldehyde Formic acid Isobutylene/isoprene copolymer Phosphorus trichloride Polyaluminum chloride Potassium oxalate Rapeseed (Brassica campestris) oil Ricinoleic acid Silicone elastomer Sodium oleth-7 phosphate Sodium oxalate Sodium PCA Synthetic wax Tallowaminopropylamine Tallow propylene diamine Triethylenemelamine ,Urea-formaldehyde resin Vinyl acetate finishing agent, textiles permanent-press fabrics Glyoxal... 

VQ Silicones with vinyl substituents (elastomer ASTM)... 

Silicone and butadiene/acrylonitrile elastomers have been successfully incorporated into an addition polyimide adhesive LARC-13. Two approaches were used to accomplish this task. Fluorosilicone (Silastic) and vinyl-terminated (Sylgard) silicone rubbers were physically blended into the adhesive amic acid and aromatic ATBN and aromatic amine-terminated silicone elastomers were chemically reacted into the prepolymer backbone. Each of the four resins displayed a distinct and separate Tg for the resin and elastomer phases. Incorporation of elastomer particles at a concentration of 15% by weight solids resulted in a 6- to 7-fold increase in peel strength and a 3- to 5-fold increase in the fracture toughness of LARC-13. This improvement in toughness was accomplished at a sacrifice in the elevated temperature adhesive strength of the material. 

High consistency silicone elastomer consists of methyl and vinyl substituted silicones with aromatic and fluorinated functional groups in some formulations. For the most part, they are peroxide crosslinked. Items are usually compression or transfer molded (Tables 4.8). 

A large number of polymers, including latexes, vinyl plastisols, silicone elastomers (heat or RT vulcanized), and polyurethanes, may be formulated into materials for facial prostheses (38-41). The materials should be biocompatible, easy to fabricate, easy to clean, feel like real skin, translucent, stable to heat, light, and cleaning solutions, and sufficiently resilient to prevent tearing. It should be possible to modify the formulation to match skin color. No material meets all these requirements. 

The main applications, by far, are as reinforcing fillers in hydrocarbon elastomers. Organo-silanes, such as the mercapto, polysulfides, amino and vinyl are used to improve filler to polymer interactions and reinforcement. Particnlarly important uses are in tyres and in footwear. There is also significant use as a reinforcing filler in silicone elastomers. 

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