Conducting polymers are a topic of great interest in the field of mole
cular electronics as well as for sensor applications. In this paper, w
e present a model for the evaluation of the d.c. conductance of a laye
r of conductive polymers, whose thickness is negligible if compared wi
th the lateral extension. In our model all the monomers constituting a
chain are represented by resistors with a fixed value of conductance
and are disposed in a square network. The nodes of the network are str
uctured in such a way that each monomer converging to the node under c
onsideration can be connected to all the other three through resistors
of different value:, whose alternated occurrence is ruled by a probab
ilistic law. The global conductance of such a network is studied while
the values of the probabilities referred to the above-said occurrence
s are varied. Finally, the treatment of this network according to the
traditional theory of random networks is considered.