  We suggest that highly conducting oriented polymers with a fibril structure
can be modeled by a regular lattice of disordered metallic wires with a random
first-neighbor interwire coupling which mimics the cross-links between fibrils.
We show that such a model can be described by a non-linear sigma model. Within
a one-loop self-consistent approximation, we determine the position of the
metal-insulator transition as a function of interwire cross-links
concentration, interwire coupling and number of polymer chains in a wire.
