The further understanding of chain topology effect on the properties of single polymer in good solvent: Special behaviors of single tadpole chain

Chain topology strongly affects the static and dynamic properties of polymer melts and polymers in dilute solution. For different chain architectures, such as ring and linear polymers, the molecular size and the diffusion behavior are different. To further understand the chain topology effect on the static and dynamic properties of polymers, we focus on the tadpole polymer which consists of a cyclic chain attached with one or more linear tails. It is found that both the number and the length of linear tails play important roles on the properties of the tadpole polymers in dilute solution. For the tadpole polymers with fixed linear tail length and number, with increasing the degree of polymerization of tadpole polymers, a transition from linear-like to ring-like behavior is observed for both the static and dynamic properties. By studying the radii of gyration for different chains, we define a ratio of the number of monomers in linear tails (N_tail) to the total degree of polymerization (N), and found that when the ratio N_tail/N is more than about 0.73, tadpole chains behave as linear chains, while, when N_tail/N is less than about 0.29, they behave as ring chains. This result will be helpful in further understanding of the chain topology dependence on the static and dynamic properties of polymer in dilute solution. Furthermore, the tadpole polymers behave as what Zimm theory expected before they deviate from the linear-like regime, or after they reach the ring-like regime, however, in the intermediate regime, the behavior of tadpole polymer does not show what Zimm model expected.