A variety of hollow structures with unique morphologies were manufactured with
a rotational spinning technique. Phase separation of soluble solutions or emulsions
was induced within a filled mold as it was being rotated about one of its axis.
The density difference between phases results in sediment at the inner lumen of
the mold under centrifugal forces. After or during sedimentation, gelation of the
phase-separated particles fixes the hollow structure morphology and the solvent
remains in the center of the mold. The solvent is removed from the mold resulting
in a coating or tube. By controlling the rotational speed and the formulation chemistry,
the tube dimensions and wall morphology can be manipulated. This technique offers
a new approach to the manufacture of polymeric tubes. It requires small quantities
of starting material, permits multi-layering of tubes, is applicable to diverse
polymers and can result in highly diffusive hollow structures while maintaining
good mechanical strength.