Patent ID: 6210364
Filing Date: 2001-04-03
Classification: A61L,A61M,B29C,B29L

Abstract:
A balloon characterized by an improved overall combination of distensibility, elastic stress response and wall tensile strength made by the process comprising:a. providing a parison of a block copolymer composition including a block copolymer having regions of (i) hard segments defined by regions of inter-molecular chain interaction separated by (ii) soft segments defined by regions in which individual polymer chains have the ability to uncoil, said parison having a predetermined initial outer diameter, a predetermined initial wall thickness and a predetermined initial length;b. subjecting said parison to at least one axial stretch step and at least one radial expansion step at temperature T.sub.1 which is below the melting temperature of said block copolymer composition to increase the diameter and length of said parison to at least three times the initial diameter and at least two times the initial length and to decrease the initial wall thickness to at least 20% of the initial wall thickness to form an expanded parison; andc. heating said expanded parision to a temperature of T.sub.2 which is above T.sub.1 but below the melting temperature of said block copolymer composition; andd. cooling said expanded parison to produce said balloon; wherein the ratio of said hard segments to said soft segments provides said balloon with (a) an elastic stress response not greater than 5.00, (b) a wall tensile strength of at least about 14,000 psi and (c) a distensibility of between about 5% and about 20%.