Dimethylsiloxane-methylphenylsiloxane

Dimethylsiloxane/methylphenylsiloxane copolymer anisole 2-propanone 2000SCH 2000SCH... 

Resistance to degradation or cross-linking by radiation is also important.2,206 This is one advantage that poly(methylphenylsiloxane) has over poly(dimethylsiloxane) the phenyl groups are efficient energy sinks that tend to suppress the usual effects of radiation on a polymer. 

Thermal decomposition of poly(alkylsiloxane) copolymers is similar to that of poly(dimethylsiloxane), the main compound generated from the siloxane moiety being cyclic siloxanes. The results for a Py-GC/MS analysis of a sample of poly(dimethyl-siloxane-co-methylphenylsiloxane) with phenyl/methyl mole ration 1/1 are shown in Figure 16.1.2. The polymer idealized formula is [-Si(CH3)20-]x [-Si(CH3)(C6H5)0-]y where x = y. The pyrolysis was done at 600° C in He with the analysis done in the same conditions as for other examples previously discussed (see Table 4.2.2). The peak identification for the chromatogram was done using MS spectral library searches only and it is given in Table 16.1.4. 

Experiments were performed on DC745U and M97 silica-filled silicone polymers as described elsewhere [1-5]. The gum stocks for all formulations were co-block polymers of dimethylsiloxane, diphenylsiloxane, methylphenylsiloxane, and/or methylvinyl siloxane. The gum stock was reinforced with high surface area silica filler and crosslinked with peroxide curing agents. These materials were tested in both new as well as service return conditions. 

C2H60Si-C7H80Si- C3H60Si (dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane) copolymer 392... 

Development Specialist, Dow Coming Corporation, Midland, Michigan Poly(dimethylsiloxane) Poly(methylphenylsiloxane)... 

Synonyms Dimethyl/phenylmethyl siloxane copolymer Dimethyl, phenylmethyl siloxane, tri methyl -term i nated Di methyls loxane methylphenylsiloxane copolymer Phenylmethylsiloxane-dimethylsiloxane copolymer Poly (dimethylsiloxane-co-methylphenylsiloxane)... 

Poly (dimethylsiloxane-co-methylphenylsiloxane). See Phenylmethyl/dimethylsiloxane copolymer Polydimethylsiloxane, diacetoxymethyl-terminated. See (Chloropropyl) methylsiloxane-dimethylsiloxane copolymer Polydimethylsiloxane elastomer. See Silicone elastomer... 

Kuo, C. M. Clarson, S. J. Semiyen, J. A., Studies of Cyclic and Linear Poly(dimethylsiloxanes) 31. Effect of Molecular Architecture/Topology on Blends of Poly(methylphenylsiloxane) and Poly(dimethylsiloxane). Polymer 1994, 35,4623-4626. 

Zhang, X. K. Poojari, Y. Clarson, S. J., A Comparison of Poly(methylphenylsiloxane) and Poly(dimethylsiloxane) Membranes for the Removal of Low Molecular Weight Organic Compounds from Water by Per-vaporation. In Science and Technology of Silicones and Silicone-Modified Materials, Clarson, S. J. Fitzgerald, J. J. Owen, M. J. Smith, S. D. Van Dyke, M. E., Eds. American Chemical Society Washington, DC, 2007 Vol. 964, pp 165-175. 

An intensive investigation has been made of the thermal degradation of poly(dimethylsiloxane) and poly(methylphenylsiloxane). " The main products are a mix of all the possible stereoisomeric cyclic trimers and tetramers together with small amounts of pentamer and cyclic oligomers. In the degradation of poly(dimethylsiloxane) fluids, however, significant amounts of linear products are... 

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