Shaken chains that spontaneously unmix themselves

Two ball chains (the kind you find on light switches or inside toilets) are shaken on a slot shaped horizontal plate. The shaking provides something like temperature and the chains are something like 2D self-avoiding polymers. The two chains are each 176cm long and identical except that they are colored red and blue. After a while, they exhibit a kind of phase separation in which they each occupy non-overlapping regions of the plate. They sometimes form spirals and occasionally cross themselves. This s