Method of fabricating an implantable medical device by controlling crystalline structure
First Claim
Patent Images
1. A method for fabricating an implantable medical device, the method comprising:
- radially expanding a polymer tube by applying stress while maintaining the polymer tube at a temperature range of from Tg to 0.6(Tm−
Tg)+Tg;
maintaining the expanded polymer tube in the expanded state at a temperature range of from Tg to 0.9(Tm−
Tg)+Tg for a sufficient period of time to heat set the polymer tube; and
fabricating the implantable medical device which is a stent from the heat set polymer tube, wherein the fabricating comprises forming a pattern in the heat set polymer tube by cutting which forms a scaffolding including interconnecting structural elements.
1 Assignment
0 Petitions
Accused Products
Abstract
A method of fabricating an implantable medical device that includes deforming and heating setting a polymer construct, for use in fabricating the device, in a temperature range in which the crystal nucleation rate is greater than the crystal growth rate is disclosed.
323 Citations
14 Claims
-
1. A method for fabricating an implantable medical device, the method comprising:
-
radially expanding a polymer tube by applying stress while maintaining the polymer tube at a temperature range of from Tg to 0.6(Tm−
Tg)+Tg;maintaining the expanded polymer tube in the expanded state at a temperature range of from Tg to 0.9(Tm−
Tg)+Tg for a sufficient period of time to heat set the polymer tube; andfabricating the implantable medical device which is a stent from the heat set polymer tube, wherein the fabricating comprises forming a pattern in the heat set polymer tube by cutting which forms a scaffolding including interconnecting structural elements. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method for fabricating an implantable medical device comprising:
-
radially expanding a polymer tube at a first temperature greater than a Tg of the polymer; wherein the polymer tube is made of poly(L-lactic acid), wherein the radial expanding increases strength of the polymer tube, induces crystallization in the polymer tube, and induces circumferential orientation in the polymer tube; maintaining the radially expanded polymer tube in the expanded state at a second temperature greater than the Tg of the polymer for a time period sufficient for a stent formed from the polymer tube to support a lumen in a deployed state, wherein the first temperature during the radial expanding and the second temperature during the maintaining are controlled such that the crystal nucleation rate of the polymer tube is greater than the crystal growth rate which maintains the increased strength and induced orientation and results in small sized crystallite domains that increase fracture toughness of the polymer tube; and fabricating the stent from the polymer tube following the maintaining, wherein the fabricating comprises forming a pattern in the polymer tube by cutting which forms a scaffolding including interconnecting structural elements. - View Dependent Claims (8, 9, 10, 11, 12, 13)
-
-
14. A method for fabricating an implantable medical device, the method comprising:
-
radially expanding a polymer tube by applying stress while maintaining the polymer tube at a temperature range of from Tg to 0.6(Tm−
Tg)+Tg;maintaining the expanded polymer tube in the expanded state at a temperature range of from Tg to 0.9(Tm−
Tg)+Tg for a selected period of time,wherein the polymer construct after the radial expanding and the maintaining has crystalline domains less than 10 microns; and fabricating the implantable medical device which is a stent from the heat set polymer tube.
-
Specification