A modified Potts model for the interaction of surface-attached polymer   complexes
  We present a simple yet generic model for the behavior of a system of many surface-attached flexible polymers with rigid side chains. Beyond its potential application in describing the dynamics of the extracellular matrix of mammalian cells, the model itself shows an interesting phase transition behavior since the underlying models (a two-dimensional Potts model and a XY-model) undergo different phase transitions. 
Marcel Hellmann, Youjin Deng, Matthias Weiss and Dieter W. Heermann