  We study the mechanical and conformational properties of networks of helical
polymers with a combination of Monte Carlo simulations based on the Wang-Landau
algorithm and the Three-chain Model. We find that the stress-strain behavior of
these networks has novel features not observed in typical networks made of
synthetic polymers. In particular, we find that as these networks are stretched
they first strengthen, then soften and finally strengthen again. This
non-monotonic behavior of the stress correlates with the one of the helical
content and is rationalized by the elongation-induced formation and melting of
the helical structure of the polymer. We complement these results with a study
of other conformational properties of the polymer strands that clarify the
molecular mechanisms behind the mechanical behavior of these networks. Finally,
we present a qualitative comparison of some of our results with the theoretical
ones recently reported by Kutter and Terentjev.
