Medical balloon

Abstract

Low polymer stress balloons are made by expanding a tube radially while allowing the ends of the tube to move axially in response to the radial expansion.

1 - 38 . (canceled)  
     
     
         39 . A medical balloon comprising a block copolymer having a cylindrically-shaped region exhibiting a birefringence pattern of substantially parallel lines before and after an exposure to temperatures of about 32° C. to about 60° C.  
     
     
         40 . The balloon of  claim 39 , wherein the cylindrically-shaped region has a length between about 1.5 cm and about 14 cm.  
     
     
         41 . The balloon of  claim 39 , wherein the cylindrically-shaped region has an outer diameter between about 1 mm and about 12 mm.  
     
     
         42 . The balloon of  claim 39 , formed of a polymer having regions of different hardness.  
     
     
         43 . The balloon of  claim 39 , wherein the block copolymer includes hard segments and soft segments.  
     
     
         44 . The balloon of  claim 39 , wherein the block copolymer comprises a material selected from a group consisting of a polyether-ester elastomer, a polyester elastomer, and a polyether block amide.  
     
     
         45 . The balloon of  claim 39 , wherein the block copolymer comprises a polyether-ester elastomer.  
     
     
         46 . The balloon of  claim 39 , comprising a material selected from a group consisting of a polyester and a polyamide.  
     
     
         47 . The balloon of  claim 39 , formed of multiple layers.  
     
     
         48 . The balloon of  claim 47 , formed of multiple coextruded layers having different hardnesses.