Conjugated polymers are attractive components of modern plastic electronics and photovoltaic devices. They are synthesized mainly through a step-growth polymerization (SGP) mechanism. However, due to the uncontrollable characteristic of classical SGP, this effort leads to batch-to-batch variations in solubility, uncontrolled molecular weight, and broad polydispersity of the polymers obtained, thus, severely limiting their processing properties and performance.Here we demonstrate a general theoretical model of controlled SGP process by examining the possibility of the polymer chains further involvement in the SGP and how this correlated with their respective molecular weights. Subsequently, we proposed a practical method by which the SGP system was confined in nano-sized reactors. This method enabled the synthesis of a variety of polymers, having precisely controlled molecular weights with narrow polydispersity. We anticipate that this venture would exemplify a starting point for a more sophisticated molecular and structural design of functional polymers in widespread applications.

The synthesis of linear polymers with both ends conserved is severely impeded due to the inevitable macrocyclization in step-growth polymerization (SGP). Indeed, macrocyclic polymers are considered as the ultimate destination...

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End-functional conjugated polymers are generally synthesized with stoichiometric-biased monomer combinations in conventional step growth polymerizations (SGPs), which lead to broad species distribution and difficult-to-control end functionality of the polymeric products due to the uncontrolled nature of the method employed. To overcome such disadvantages, a general controlled method was developed for the synthesis of narrowly distributed end-functional conjugated polymers with high-end functionality purity and a predefined molecular weight. This strategy relies on the spatial confinement effect of the nanoreactors, whereby polymeric species with higher molecular weight have a lower chance of further involvement in SGP. Numerical calculations on the kinetic equations demonstrated the formation of narrowly distributed polymers with a high degree of chain-end functionalization. Experimental results based on various analysis methods confirmed the controlled synthesis of bifunctionalized poly(p-phenylene)s with high-end functionality purity and low dispersity value down to 1.06.