Melts with topologically distinct molecular structures are investigated by molecular dynamics simulation. We determine the mean polymer size and shape, and glass transition temperature for each molecular topology. Both in terms of structure and dynamics, ring polymers behave similarly to star polymers with f = 5 to 6 arms, close to the transition point between anisotropic chains to spherically symmetric particle-like structure. These ﬁndings raise fundamental questions regarding the importance of free chain-ends and chain topology in the packing and dynamics of polymeric materials.
The Journal of Chemical Physics
star polymers, ring polymers, molecular topology, polymer melt dynamics, polymer shape and size, polymer-particle transition