  We systematically explore the self-assembly of semi-flexible polymers in
deformable spherical confinement across a wide regime of chain stiffness,
contour lengths and packing fractions by means of coarse-grained molecular
dynamics simulations. Compliant, DNA-like filaments are found to undergo a
continuous crossover from two distinct surface-ordered quadrupolar states, both
characterized by tetrahedral patterns of topological defects, to either
longitudinal or latitudinal bipolar structures with increasing polymer
concentrations. These transitions, along with the intermediary arrangements
that they involve, may be attributed to the combination of an orientational
wetting phenomenon with subtle density- and contour-length-dependent variations
in the elastic anisotropies of the corresponding liquid crystal phases.
Conversely, the organization of rigid, microtubule-like polymers evidences a
progressive breakdown of continuum elasticity theory as chain dimensions become
comparable to the equilibrium radius of the encapsulating membrane. In this
case, we observe a gradual shift from prolate, tactoid-like morphologies to
oblate, erythrocyte-like structures with increasing contour lengths, which is
shown to arise from the interplay between nematic ordering, polymer and
membrane buckling. We further provide numerical evidence of a number of
yet-unidentified, self-organized states in such confined systems of stiff
achiral filaments, including spontaneous spiral smectic assemblies, faceted
polyhedral and twisted bundle-like arrangements. Our results are quantified
through the introduction of several order parameters and an unsupervised
learning scheme for the localization of surface topological defects, and are in
excellent agreement with field-theoretical predictions as well as classical
elastic theories of thin rods and spherical shells.
