The present invention relates to a fluorine-containing macroazo compound having a fluorine segment in the molecule thereof, which is useful, for example, as a polymerization initiator or the like.
In recent years, polymeric materials have become used in more and more diversified fields, and with this trend, the properties required of polymers are also being diversified. Particularly, polymers having a perfluoroalkylene group (Rf group) in the molecule thereof are noticed with interest because the Rf group part having a low surface free energy is concentrated into the surface region of the polymer to exhibit excellent water-repellency, oil-repellency, heat resistance, weather resistance, slipping characteristics, and the like.
Hitherto, it has been attempted to introduce an Rf group-containing polymer into base material by the method of blending or the like. Such attempts, however, have not given a sufficient effect.
Thus, introduction of Rf group into polymer molecule is being attempted by various methods.
For example, a method of introducing Rf group by the reaction of a polymer formed by living anionic polymerization with an Rf group-containing alkyl halide has been reported in Polymer Preprints Japan., 44, 948 (1995), etc.
Further, methods for producing a polymer having a fluorine segment by polymerization reaction of a fluorine-containing monomer have also been disclosed. Particularly, a synthesis of block polymer using a monomer having a perfluoroalkylene group is being studied energetically because this method makes it possible to introduce perfluoroalkylene group into molecule in a high efficiency and a high concentration.
However, the method of reacting a polymer with Rf group-containing alkyl halide is limited in the kind of polymer usable, and therefore is low in reactivity. On the other hand, the method of polymerizing a fluorine-containing monomer is disadvantageous in that fluorine segment cannot be introduced into an intended site of polymer molecule and a block polymer cannot be obtained.
As a means for solving the above-mentioned problems, it has been attempted to introduce a fluorine segment through a condensation reaction between a prepolymer having fluorine-containing alkylene group and a polymer.
This method, however, cannot introduce fluorine segment in a high yield because the prepolymer having a fluorine-containing alkylene group is low in solubility.
USPTO Backgrounds
USPTO Backgrounds