Multiple arms star polymer translocation from a cylindrical cavity subject to a pulling force

A Langevin dynamics computer simulation is used to investigate the dynamics of star polymer translocation from a cylindrical cavity (tube), which is connected to a plane wall having a circular nanopore along the tube axis. Star polymers of different masses and number of arms or functionalities are considered in the present study. The translocation is carried out by applying an external pulling force which is exerted only on the end monomer of one arm. For a strong pulling force regime and for a given functionality, the translocation time exhibits a power law dependence on the polymer mass where the exponent is found to be close to 2. We have also found that the translocation dynamics of chains of constant mass but varying functionality is significantly affected by the pore radius. For wider pores, the translocation time decreases continuously as the number of arms increases, while in the case of smaller pores, the average exit time shows a non-monotonic behavior with a minimum around a critical functionality f_c. In addition, the translocation dynamics was also investigated in terms of tube length and tube aspect ratio.