Methylphenylsiloxane

The most commonly used siloxane modifiers are those having phenyl, trifluoro-propyl and cyanopropyl substituents. Introduction of phenyl units into the polydimethylsiloxane backbone either in the form of methylphenylsiloxane or diphenyl-siloxane increases the thermal and oxidative stability, glass transition temperature and the organic solubility characteristics of the resulting copolymers. At low levels (5-10 percent by weight) of incorporation, bulky phenyl groups also break up the regularity of polydimethylsiloxane chains and inhibit the crystallization (Tc... 

An interesting reaction involves the cocondensation of transition-metal atoms with liquid methylphenylsiloxane polymers at -20 to 0°C... 

The silcone resin is a poly(methylphenylsiloxane) synthesized from methylchlorosilanes and phenylsilanes . Incorporation of phenyl groups Improves the thermal stability of the silicone resin. Epoxldatlon of the resin is most likely accomplished through substitution of the oxlrane ring at varlou phenyl group sites, yeildlng an epoxlde/slloxane ratio near unity. 

Also of interest is the use of aromatic side groups different from the phenyl groups present in the commercially important poly(methylphenylsiloxane) or the highly intractible poly(diphenylsiloxane).112-119 Homopolymers and copolymers having p-tolylsiloxane groups have been of particular interest with regard to their formation of liquid-crystalline phases.120121... 

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. 

Also of interest is the recent demonstration that poly(methylphenylsiloxane) can undergo a reversible droplet-monolayer transition234 that could be very relevant to the spreading of polymers on surfaces. 

In the case of methylphenylsiloxanes, stereoisomer ring molecules are possible e.g., for the cyclic trimer, there exist a cis and a trans form and for the cyclic tetramer, there are four stereoisomer forms. Based on gas chromatography data, it has been suggested that these are in statistical equilibrium with each other at elevated temperature (117, 210). 

DBU DMC DMF EC EO EOS GSS ILs MBMTBP MEA MW PC PDMS PEG PEGda PEO PMPS PO PPG PPGda PTC PTHF PTMO PVP Diazabicyclo[5.4.0] -undec-7-ene Dimethylcarbonate Dimethylform amide Ethylene carbonate Ethylene oxide, oxyethylene Equation of state Gas-saturated solution Ionic liquids 2,2,-methylene-bis(4-methyl-6-tert-butylphenol) Monoethanolamine Molecular weight Propylene carbonate Polydimethylsiloxane Polyethylene glycol Poly(ethylene glycol) diacrylate Polyethylene oxide Poly(methylphenylsiloxane) Propylene oxide Poly(propylene glycol) Poly(propylene glycol) diacrylate Phase-transfer catalyst Poly(tetrahydrofuran) Polytetramethylene oxide Polyvinyl pyrrolidone... 

PE PEMA PEO PIP PMAA PMMA PMPS poly(ethylene) poly(ethyl methacrylate) poly(ethylene oxide) poly(isoprene) poly(methacrylic acid) poly(methylmethacrylate) poly(methylphenylsiloxane)... 

Brachais L et al. (2002) Solid-state organization of poly(methyl methacrylate)-poly(methylphenylsiloxane) based interpenetrating networks. Polymer 43(6) 1829-1834... 

Table 11. Temperatures and heat transitions of cyclolinear poly (methylphenylsiloxanes) with flexible spacers [75]...

Side-Chain Torsions in Poly(meihylphenykiloxane). Two bond torsions are possible for the side chains in poly(methylphenylsiloxane) (PMPS). 

Preparation of Exactly Alternating Copolymer of 1 4 Disiloxy-l, 4-dimethyUl, 4-disilacyclohexadiene and Methylphenylsiloxane... 

To prepare the alternating copolymer of 1,4-dimethyl-l,4-disilacyclohexadiene-1,4-siloxane and methylphenylsiloxane (Scheme VI), 5.76 g of the... 

The alternating copolymer of 1,4-disiloxy-1,4-dimethyl-1,4-disilacyclohexadiene and methylphenylsiloxane was prepared from the reaction of phenylmethyldichlorosilane and 1,4-di-... 

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