A new method for the rapid and efficient coupling of homopolymers to yield diblock and triblock copolymers as well as cyclic polymers using the 3 + 2 pi Huisgen copper catalyzed cycloaddition reaction has been developed. This facile method utilizes commercially available Cu nanoparticles that are tolerant to O-2, easily removable and recyclable. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 814-819,2011