  We provide an estimation of the dissipation of the Wasserstein 2 distance
between the law of some interacting $N$-particle system, and the $N$ times
tensorized product of solution to the corresponding limit nonlinear
conservation law. It then enables to recover classical propagation of chaos
results in the case of Lipschitz coefficients, uniform in time propagation of
chaos in the case of strictly convex coefficients. But also some recent results
as the case of particle in a double well potential.
