Borane-mediated control radical polymerization: Synthesis of chain end functionalized fluoropolymers

This paper summarizes our experimental results in a new family of borane-based control radical initiators and their unique application in the synthesis of fluoropolymers containing one or more terminal functional groups. The chemistry is advantaged by its simplicity of borane initiator and mild reaction condition, and applicable to a broad range of fluoromonomers, including VDF, f-acrylic, etc. Two type borane initiators, including cycloborane and functional borane, will be discussed to illustrate the functionalization scheme. The control radical polymerization is characterized by predictable molecular weight, narrow molecular weight distribution, formation of diblock copolymer, and tolerance to many functional groups that usually cause chain transfer reactions in regular free radical polymerization. In turn, the chain end functionalized fluoropolymers exhibit very high surface activities in the polymer/inorganic composites. For example, the polymer can exfoliate clay interlayer structure in PVDF/clay nanocomposite, and maintaining the disorder state even after further mixing with neat (unfunctionalized) polymer.