The past two decades have witnessed a rapid growth in the field of synthetic polymer chemistry,focusing on the fine control of molecular weights,molecular weight distributions,chain topologies,and sequence structures of synthetic polymers.For example,a variety of controlled radical polymerization techniques have been invented and become indispensable in the toolbox of current polymer chemists.The advent of high-efficiency coupling chemistry including copper(Ⅰ)-catalyzed cycloaddition reaction further enriches the arsenal of controlled polymer synthesis.