Collapse of semi-flexible brushes in poor solvents: Tilting and bending

We study the problem of a semi-flexible polymer brush immersed in a poor so lvent and show that the brush is unstable to collapse. We are able Co solve the problem exactly by mapping it onto one of a classical particle in a kn own potential. In contrast to the case of flexible chains, the free-energy costs of bending may result in a sharp transition to a stable tilted and be nt phase.