Hydrogen-containing flourosurfacant and its use in polymerization
申请人:E. I. du Pont de Nemours and Company
公开号:US05763552A1
公开(公告)日:1998-06-09
A partially-fluorinated surfactant having internal methylene groups and having the formula R.sub.f --(CH.sub.2).sub.m --R'.sub.f --COOM wherein m is 1-3, R.sub.f is perfluoroalkyl or perfluoroalkoxy, containing 3-8 carbon atoms, R'.sub.f is linear or branched perfluoroalkylene containing 1-4 carbon atoms, and M is NH.sub.4, Li, Na, K, or H is useful in polymerization of fluorinated monomers. High molecular weight can be achieved in homopolymerization of tetrafluoroethylene.
Iodonitriles as chain transfer agents in the manufacture of
申请人:E. I. du Pont de Nemours and Company
公开号:US06166157A1
公开(公告)日:2000-12-26
Iodoperfluoroalkylnitriles are useful as chain transfer agents in the free radical polymerization of vinyl monomers to form perfluoropolymers. These nitrites provide end groups, which may take part in a cross-linking reaction, if desired, and also have a relatively low toxicity. The resulting perfluoropolymers are useful as molding resins and elastomers, particularly for parts where good chemical resistance and/or high temperature resistance are desirable.