Loop entanglement of semicrystalline polyethylene in amorphous region: Diamond lattice approach

Linear polyethylenes in the amorphous region have been simulated as restric ted random walks on a diamond lattice between two absorbing planes. The lin ks among loops were studied by treating loops as oriented curves. The local conformations of polyethylene chains (i.e., trans and gauche energy differ ences) were considered in the simulation, thereby determining the effect of crystallization temperature on the loop entanglement. It was found that th e total Gauss winding and kink density of linked loops increased with the t hickness of the amorphous region. This result agrees with that of the cubic lattice model. The link probability decreases very slowly with the thickne ss of the amorphous region. On the other hand, the results presented clearl y indicate that all statistical measures of linked loops decrease with temp erature. (C) 1999 John Wiley & Sons, Inc.