Molecular dynamics (MD) simulations have been used to study the melting of alpha- and beta-poly (vinylidene fluoride) (alpha- and beta-PVDF). It is seen that melting at the ends of the polymer chains precedes melting of the bulk crystal structure. Melting of alpha-PVDF initially occurs via transitions between the two gauche dihedral angles (G -> G') followed by transitions between trans and gauche dihedral angles (T <-> G/G'). Melting of beta-PVDF initially occurs via T -> G/G' transitions and via transitions of complete beta- (TTTT) to alpha-(TGTG') quartets. The melting point of beta-PVDF is higher than that of a-PVDF, and the simulated melting points of both phases depend on the length of the polymer chains used in the simulations. Since melting starts at the chain ends, it is important to include these in the simulations, and simulations of infinitely long chains yield melting points far larger than the experimental values (at least for periodic cells of the size used in this work), especially for beta-PVDF. The simulated heats of fusion are in agreement with available experimental data. (C) 2012 Elsevier Ltd. All rights reserved.