CRIMPING POLYMER SCAFFOLDS

摘要

A polymer scaffold is crimped to a balloon while the polymer material is in a thermodynamically unstable state, or a transient state including crimping shortly after a tube or scaffold processing step that imparts memory to the material, or shortly after rejuvenation of the scaffold.

主权项

1. A method for making a medical device, comprising:
providing a tube made from a material comprising a polymer composition having a glass transition temperature (Tg) and melting temperature (Tm), the tube being formed by, or modified by a forming process, wherein the forming process includes the step of at least one of raising the temperature of the tube to about, or greater than about Tg or radially straining the material beyond a yield strain for the material; making a scaffold from the tube formed or modified by the forming process; and crimping the scaffold to a balloon such that a significant plastic deformation is imposed on the scaffold when crimped to the balloon, including the steps of
reducing a scaffold diameter from a pre-crimp diameter to a first diameter,rejuvenating the scaffold including radially expanding the diameter from the first diameter to a second diameter, andreducing the scaffold diameter from the second diameter to a third diameter that is less than the first diameter.