Effect of Branch Point Distribution on the Radius of Gyration in Batch Free‐Radical Polymerization with Chain Transfer to Polymer

Abstract

AbstractFree‐radical polymerization is irreversible, and the primary chains formed earlier are expected to possess larger branching density compared with those formed later, leading to a branching density distribution (BDD) among primary chains. In addition to the BDD, the primary chain length distribution (CLD) may change during polymerization. For a primary CLD with a shift toward smaller chain length during polymerization, the expected g‐ratio for a given number k of branch points can be approximated reasonably well with that for the random branched polymers having the accumulated primary CLD. On the other hand, when the primary CLD moves toward larger chain length during polymerization, the expected g‐ratio may become smaller than the corresponding random branched polymers, due to an “unnatural” combination in the length of backbone and branch chains. The compactness of branched architecture could be controlled through the consideration of the maximum end‐to‐end path length.