Borane-containing polyolefins: Synthesis and applications

This article summarizes the experimental results in the synthesis and applications of borane containing polyolefins. It is becoming clear that the introduction of borane groups into polyolefins, such as polyethylene (PE) and polypropylene (PP), is a valuable route for achieving their functionalization, which has been a long scientific challenge and industrial needed technology. The trialkyborane moieties, unlike other organic functional groups, are stable to early transition metal (Lewis acid) complexes and compatible with olefin monomers. Therefore, borane-containing monomers can be effectively incorporated into polyolefins via Ziegler-Natta and metallocene copolymerization reactions. In turn, the borane group that is incorporated into the polymer not only can be quantitatively converted to a hydroxy group, but it also can be transformed into a stable polymeric radical that then initiates a living free radical polymerization of the functional monomers. The functional group and functional group concentration are basically governed by the monomers that are introduced. The resulting graft and block copolymers, having well-controlled molecular structures, would be very difficult to prepare by existing methods.