  Polymers in confined spaces are compressed and have reduced conformational
entropy, and will partially or fully escape from confinement if conditions are
suitable. This is in particular the case for a polymer grafted in a pore. The
escape of the polymer from the pore may be considered a partial translocation
from the pore into bulk solution, and the resulting conformational readjustment
of the polymer has characteristics of a thermodynamic phase transition. In this
paper a lattice self-avoiding walk model of a star polymer grafted in a pore is
examined numerically using the PERM algorithm. We show that the arms of the
grafted lattice star escape one at a time as the length of the pore is reduced,
consistent with earlier results in the literature. Critical points for the
escape transitions are estimated for square and cubic lattice models and we
also examine various properties of the model as it undergoes escape
transitions.
