Dendrites are branched lamellas with the branches related in a definite crystallographic way to each other. Branching occurs under conditions in which crystal growth from solution is fast relative to the diffusion of polymer molecules to the crystallization site.

  Dendritic structures are found for solution crystallized polyethylene, with branches along the crystallographic a and b axes, perpendicular to the chain direction in the lamellas.

Fig. 8. Polymer dendrites (partial views) : A. polyethylene, B. polypropylene.