Methylsiloxane copolymers

Table 12. Homolog series of cyclolinear methylsiloxane copolymer pyrolysis...

Column Glass U-tubes, 6 foot X 4 mm. i.d. Gas Chrom P, 80-100 or 100-120 mesh, acid-washed dichlorodimethyl-silane treated. Two types of packing used 10% neopentyl glycol succinate (NGS) and a two-component phase consisting of 7% silicone oil F-60 with 1% ethylene glycol succinate-phenyl methylsiloxane copolymer (EGSS-Z). Condition-... 

Another tjqie of comb like amylose hybrids synthesized via enzymatic grafting with phosphorylase is based on polysiloxane backbones. To achieve these structures double bonds were incorporated to the reducing end of oligosaccharides which were then attached to poIy(dimethylsiloxane-co-methylsiloxane) copolymers via hydrosililation or to silane monomers which were subsequently polymerized to polysiloxanes . Various mono-, d>-, tri and oligosaccharides were attached to siloxane backbones and their solution properties were studied with viscosimetry and static and dynamic light... 

Figure 6.20 Diffraction patterns of comb-type methylsiloxane copolymers with phenylcyclo-trisiloxane fragments in the side chain. Where curve 1 copolymer XIX,...

In the modification reaction using the reaction of hydrosilylation, the authors successfully used trimethylsiloxy end blocked methylhydridesiloxanes [38, 39]. By hydride addition of unsaturated organic compounds, allyl glycidyl ether [40,41], allyl alcohol [42,43] or dicyclopentadiene [39,44] to methylhydridesiloxanes in the presence of a catalyst, comb-type methylsiloxane copolymers has been obtained. 

The synthesised copolymers are light-yellow liquid or solid systems, depending on the length of dimethylsiloxane chain, dissolve well in ordinary organic solvents, with tl p of 0.05-0.07. The structure and composition of synthesised copolymers was determined by means of elementary analysis, by IR and NMR spectra data. Some physical-chemical properties of comb-type methylsiloxane copolymers with carbocyclosiloxane fragments in the side chain are presented in Table 6.12. 

Dimethylsiloxane/(4-acetylbutyl)methylsiloxane copolymer carbon dioxide 2003K1L... 

Dimethylsiloxane/(3 -ethoxypropyl)methylsiloxane copolymer carbon dioxide 2003KIL... 

A few years earlier, in 1991, Williams et al. [22] had performed the structural analysis of poly(tetramethyl-p-silphenylene siloxane)-poly(di-methylsiloxane) copolymers (TMPS-DMS copolymers) by Si NMR. These copolymers were obtained by the condensation of bis-hydroxy(tetramethyl-p-silphenylene siloxane) 1 with a, tw-dihydroxy polydimethyl oligosiloxanes, in the presence of a guanidinium catalyst (cf. Scheme 8) ... 

Hexylmethylsiloxane-(a-methylphenethyl) methylsiloxane, copolymer. See Hexylmethylsiloxane/2-phenylpropylmethylsiloxane copolymer Hexyl methyls I oxane/2-phenylpropylmethylsiloxane copolymer CAS 68952-01-2... 

The procedure described here is not limited to the preparation of polymers such as 2. Starting from the difunctional silane 3 we have synthesized a copolymer, poly(dimethyl-co-isocyanopropylmethyl-siloxane) > as well as a linear homopolymer, poly(isocyanopropyl-methylsiloxane) 8 (Scheme 2). Indeed, preparation of a monofunctional analogue of 2. and h creates the potential for end-capping with an isocyanide function any polymer containing other functional groups, thereby in principle permitting mixed ligand complexes of polymers to be accessed. 

The low thermal stability and the volatility of some of the low molecular weight stationary phases restricted their general use. Therefore, thermally stable and nonvolatile polymeric chiral stationary phases were developed by coupling the diamide phase, via the amino functionality, to a statistical copolymer of dimethylsiloxane and (2-carboxypropyl)methylsiloxane of appropriate viscosity131. The fluid polymeric phase, referred to as Chirasil-Val (Table 2), exhibits excellent properties for the enantiomer separation of a variety of compound classes over a broad temperature range141142. 

JorzikU, Wolf BA (1997) Reduction of the interfacial tension between poly(di-methylsiloxane) and polyethylene oxide) by block copolymers Effects of molecular architecture and chemical composition. Macromolecules 30(16) 4713-4718... 

Furthermore, at the increase of cyclic fragment volume, i.e. at transition from organocyclotetra-siloxane fragment to organocyclopenta- and organocyclohexasiloxane ones, at the same length of di-methylsiloxane unit induces a decrease of thermal oxidative stability of the copolymers, which, in turn, is explained by increase of the mass part of phenyl groups. 

Thus, for the first time methylsiloxane oligomers and copolymers with various cyclic fragments in the side chain were synthesised by us and it was shown that cyclic fragments in the side chain behave in thermal destruction processes as cyclic fragment in the main chain. 

L.M. Robeson, A. Noshay, M. Matz-NER, C. N. Merriam, Physical property characteristics of polysulfone/poly(di-methylsiloxane) block copolymers. An-geiv. Makromol. Chemie 29/30 (1973) 47. 

Chems. http //www.jlic.com.cn Trade Name Synonyms C3290 [United Chem. Tech, http //www.unitedchem.com] (Chloropropyl) methylsiloxane-dimethylsiloxane copolymer CAS 70900-20-8... 

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