FIuori nated

The Grignard reaction is one general method for the access to fiuori-nated phosphines [118]. Fluor mated phosphines are also related to catalysis applications in fluorous reaction media [119-121]. As a first example, trans-Co2(CO)6[P(z-Pr)2 3,5-fozs(CF3)-C6H3 ] (5b) was synthesized in two steps by the reaction of 3,5-fozs(CF3)-C6H3MgBr with (z-Pr)2PCl to 5a with a yield of 90%, followed by the complexation of Co2(CO)8 in refluxing benzene (Fig. 10). 

In addition to chlorinated and brominated natural products, a few dozen fiuori-nated and iodinated metabolites have also been characterized. Since the energy to oxidize a fiuoride is prohibitively high, it is not surprisingly that nature uses a... 

The substituents may be halides, such as fluorine, chlorine or iodine, as well as hydrogen. As they are not retained during the reaction, they do not have any influence on the constitution of the formed carboxylic acid. This is a convenient procedure for the preparation of a-fiuori-nated carboxylic acids, especially perfluorinated acids and chlorofluoroalkanecarboxylic acids. 

The top-coats are responsible for the durability and resistance to water and chemical impacts from the environment. Mainly acrylic and fiuori-nated polymers are used for top-coats on various base coats (PVC, PUR, PTFE, silicone rubber, etc.) to enhance resistance to soiling and ageing. Certain additives for UV protection can be added. Due to its self-cleaning non-adhesive surface the top-coat is often hard and brittle. On PVC coatings the top-coat gives not only protection against environmental infiuences but also a barrier against emission of plasticizer out of the PVC. 

Other studies have focused on poly(dimethylsiloxane) blended with polycarbonates, ° polyisobutylene, poly(ethylene oxide), polyurethanes, epoxies,benzoxazines, and poly(hexylthiophene). ° In some cases, a polysiloxane oil was blended into polypropylene to facilitate its processing. A variety of other siloxane materials have been employed—for example, poly(diethylsiloxane), polyurethanes, fiuori-nated siloxane copoymers and fluororubbers in general, and trimethyl-siloxy silicates. ... 

Precaution Flamm. flamm. limits 1.2-10.7% vol. in air avoid heat, flame, sources of ignition keep away from strong oxidizing materials Hazardous Decomp. Prods. Combustion prods. CO, COj, silicon compds., fiuori-nated compds., fonnaldehyde Storage Reclose containers immediately after use BYK -345 [BYK-Chemie GmbH BYK-Chemie USA]... 

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