Update on fluoroelastomers: from perfluoroelastomers to fluorosilicones and fluorophosphazenes

A survey of the synthesis, properties and applications of fluoroelastomers is reported failing into two main parts. After describing commercially available (per)fluorocarbon elastomers, fluoro-phosphazenes and silicones, recent data on hybrid fluorosilicones containing longer chains (often fluorinated) between silicon atoms are supplied. The second part deals with well-architectured fluoroelastomers. First, fluorinated thermoplastic elastomers obtained either by sequential iodine transfer polymerisation of fluoroalkenes (leading to triblock copolymers) or by a two-step procedure involving a monomer bearing peroxide that generated macroperoxides which thus produced graft copolymers. Then, multiblock copolymers were achieved either from telechelic perfluoropolyethers or from polyhydrosilylation of telechelic non-conjugated diene polyimides with fluorinated polyhybrid siloxane bearing Si-H end groups leading to exceptional materials. (c) 2004 Elsevier B.V. All rights reserved.