Polysiloxanes fluorinated

Polysiloxanes containing a-cyano and a- or ]]-fluorine substituents are. thermally labile at comparatively low temperatures and are not used in gas chromatography. Polysiloxane phases containing 3,3,3-trifluoropropyl groups are thermally Stable up to about 250-275 C and possess rather unique selectivity, particularly for electron-donor solutes, such as ketones and nitro groups. The electronegative trifluoropropyl... 

Mention has already been made of the effectiveness of corona or plasma treatment in increasing the influence of subsequent or concurrent polymer treatment. As examples of polymers used in this way, mention can be made of reactive cationic polysiloxane [294] and polymerisation on the fibre of tetrafluoroethylene or hexafluoropropylene [299]. Water repellency was also improved by the fluorinated polymers. Tetrafluoroethylene gave superior shrink resistance this polymer covered the scale edges of the wool, whereas this did not occur with poly(hexafluoropropylene). 

So, if these hybrid homopolymers exhibit interesting properties at high temperatures, their properties at low temperatures are poorer than those of the classical polysiloxanes, which is why we decided to study fluorinated hybrid polysiloxanes containing the telomers prepared above. 

Kunzler et al. (5) prepared silicone hydrogels containing vinyl carbonate end-capped with fluorinated polysiloxanes that had an oxygen permeability of at least about 120 Barters, a water content of at least about 20wt%, and high modulus. 

Block and graft copolymers were prepared by Akutin, Parlashke-vich, Kogan, Kalinina, and Menes (128) by the use of ultrasonics on solutions of fluorine containing polymers or polysiloxanes on one hand and polymethyl methacrylate, polyvinyl chloride, ethylcellulose on the other. 

Two other families of polymers with fluorinated side groups have been investigated in the field of elastomers polysiloxanes and polyphosphazenes [394, 395]. These latter macromolecules, called NPF, have been obtained by chemical change of poly(dichlorophosphazene) as for classic phosphazenes ... 

Concerning fluorinated polysiloxanes, the most common and commercially available (by Dow Corning) has the following formulae ... 

Hydrosilylation is by far the most important route for obtaining monomers and other precursors to fluorinated polysiloxanes. Hydrosylilation80 is the addition of silicon hydride moiety across an unsaturated linkage using transition metal complexes of platinum or rhodium such as Speier s catalyst, hexachloroplatinic acid in isopro-... 

Titanates have been instrumental in the bonding of fluorinated resins to packaging films, poly(hydantoin)—polyester to polyester wire enamel, polysulfide sealant to polyurethane (a phosphated titanate is recommended), polyethylene to cellophane using a titanated polyethylenimine, and silicone mbber sealant to metal or plastic support using polysilane (Si—H) plus polysiloxane (Si—OR) and titanate as the adhesive ingredients (450—454). Polyester film coated first with a titanium alkoxide, then with a poly(vinyl alcohol)—polyethylenimine blend, becomes impermeable to gases (455). 

Abstract This article summarizes a large amount of work carried out in our laboratory on polysiloxane based Interpenetrating Polymer Networks (IPNs). First, a polydimethylsiloxane (PDMS) network has been combined with a cellulose acetate butyrate (CAB) network in order to improve its mechanical properties. Second, a PDMS network was combined with a fluorinated polymer network. Thanks to a perfect control of the respective rates of formation of each network it has been possible to avoid polymer phase separation during the IPN synthesis. Physicochemical analyses of these materials led to classify them as true IPNs according to Sperling s definition. In addition, synergy of the mechanical properties, on the one hand, and of the surface properties, on the other hand, was displayed. 

The preparation of a fluorinated polysiloxane elastomer with silyl benzene moieties (called FASIL) was described by Loughran and GrifiBn [38]. The authors obtained a high molecular weight polymer by optimization of the polymerization conditions (cf. Scheme 16) ... 

More recently, we have also reported the synthesis of thermoplastic siloxane elastomers based on hybrid polysiloxane/polyimide block copolymers (the hybrid polysiloxane being fluorinated or not) that were obtained through polyhydrosilylation of dienes with a,dihydrooligosiloxanes [76-78], as follows ... 

New Fluorinated Polysiloxanes with High Performance in Textile Applications... 

The solubility of the polysiloxane in organic solvents is reduced by introducing fluorine into the position y to silicon. This also increases the thermal stability. The monomers can be synthesized according to... 

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