Hybrid copolymers, fluorinated

Then, they considered fluorinated hybrid copolymers (cf Scheme 20). These copolymers were prepared by condensation of hybrid bis-silanol monomers and dichloro or diacetamido silanes, in the presence of a monofunctional silane as the chain stopper, according to the following scheme ... 

During the year 1970, several articles were published by Kim et al. [41-46] about the synthesis and the properties of fluorinated hybrid silicone homopolymers and copolymers. These polymers were obtained by hydrosilylation of a, (D-dienes with chlorohydrogenosilanes, and the obtained bis-chlorosilanes were then hydrolysed into bis-silanols and polymerized or copolycondensed (R = R or R or R or R, Z = alkyl, aUcyl ether, fluoroalkyl, fluoroether, etc.) (cf. Scheme 19). 

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 ... 

Then they used these fluorinated PBIs for the preparation of the hybrid nanocomposite by mixing it with a silica precursor, tetraethoxysilane (TEOS), in a DMAc solution followed by hydrolysis and solution casting (Figure 5.19). The compatibility of the fluorine-containing PBI copolymer with the inorganic silica phase was good, and the bonding site enhanced the interfacial interaction between PBI chains and silica nanoparticles [33]. 

In contrast to previous manufacturing approaches, it is proposed that the infusion of volatile precursors of inorganic and metal-oxide nanoparticles into free volume of polymers is a more practical and effective strategy for the dispersal of discrete nanoscale particles. To this end, hybrid films containing Pd nanoparticles have been obtained through infusion the metal nanoparticles have been shown to have a strong catalytic effect on the gas transport through fluorinated ethylene-propylene copolymer (FEP) (Yu etal.,2004). 

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