Advanced Cardiovascular Systems, Inc.

Raychem Limited

Robert P Saltman

Ketan P Muni

Udayan G Patel

Tai Chun Cheng

Ziyun Chen

Murthy V Simhambhatla

Edward F Chu

Vijay N Reddy

Robert D Ainsworth

George B Park

James A Rinde

Stephen Michael Baigrie

Jeong Soo Lee

A combination of polymeric components provides desired characteristics in forming medical instruments such as catheters and balloons for dilatation catheters. For example, a balloon material is formed from a blend of polymeric components, including a first crystalline polymeric component and a second softening polymeric component. Where the first two components are generally incompatible, the balloon material can also include a third compatibilizing agent to facilitate blending the first two polymeric components together.

Polymer blends for use in making medical devices including catheters and balloons for dilatation catheters

A dimensionally stable and growth controlled inflatable member formed by adding a multifunctional agent to a soft polymer to form a compound, extruding an inflatable member from the compound, and crosslinking the compound. The inflatable member is configured to be formed-in-place with a body lumen. Preferably, the inflatable member is blown to a working diameter prior to use and then heated to the glass transition temperature of the polymer to shrink the diameter of the blown inflatable member back to about the nominal diameter of the tubing. In another embodiment, the invention is a dimensionally stable and growth controlled inflatable member comprising longitudinal zones of crosslinked material symmetrically spaced about the circumference of the inflatable member and a uniform working diameter. Preferably, there are three or more longitudinal zones that run the working length of the inflatable member. The selectively irradiated inflatable members are formed in a mold having symmetrically spaced longitudinal windows.

Dimensionally stable and growth controlled inflatable member for a catheter

Medical devices such as catheter balloons, stent covers and vascular grafts formed of ultrahigh molecular weight polyethylene. The devices are formed from polyethylene that has been processed so that it is microporous and has an oriented node and fibril structure. The balloons expand compliantly at low strains and are substantially less compliant at higher strains. The invention also comprises methods for making such balloons, including the steps of compacting a polyethylene powder and deforming it to impart the oriented structure.

Process of making a balloon for an intraluminal catheter

Medical device formed of ultrahigh molecular weight polyethylene

A combination of polymeric components provides desired characteristics in forming medical instruments such as catheters and balloons for dilatation catheters. For example, a balloon material is formed from a blend of polymeric components, including a first crystalline polymeric component and a second softening polymeric component. Where the first two components are generally incompatible, the balloon material can also include a third compatibilizing agent to facilitate blending the first two polymeric components together. The first polymeric component can be a branched or straight chain polyamide having a molecular weight of at least about 5000, or a polyester prepared from aromatic dicarboxylic acids having 8 to 14 carbon atoms or aliphatic dicarboxylic acids having from 2 to 12 carbon atoms, and at least one glycol having the formula HO(CH.sub.2).sub.n OH, where n is an integer from 2 to 10, neopentyl glycol and cyclohexane dimethanol. The second polymeric component can be a polyolefin, an ethylene copolymer, a polyester block copolymer, or a polyamide block copolymer. The third polymeric component is preferably an ethylene copolymer having the formula E/X/Y where E is ethylene; X is an .alpha., .beta.-ethylenically unsaturated monomer derived from at least one of alkylacrylate, alkylmethacrylate, alkyl vinyl ether, carbon monoxide, sulfur dioxide, or mixtures thereof, where the alkyl groups contain 1-12 carbon atoms; and Y is an .alpha., .beta.-ethylenically unsaturated monomer containing a reactive group that forms a covalent bond with the first polymeric component. The polymeric blend can be irradiated to enhance the properties of the balloon material, including significantly increasing burst pressures.

Polymer blends for use in making medical devices including catheters and

A catheter and/or balloon for a medical catheter is formed from a blend of polymeric components, including a first crystalline polymeric component and a second softening polymeric component. The polymeric material can also include a third compatibilizing agent to facilitate blending the first two polymeric components together. The first polymeric component can be a polyester or a polyamide, and the second polymeric component can be a polyolefin, or an ethylene copolymer. The third polymeric component is preferably an ethylene copolymer containing a reactive group that forms a covalent bond with the first polymeric component. The polymeric material forming the balloon or catheter also can include a catalyst to catalyze a reaction between the compatibilizing ethylene copolymer and the second polymer component. The second, softening polymeric component can also include a silane coupling agent, to provide a reactive softening copolymer that bonds with the first strong polymeric component, to provide increased flexibility of catheters and balloons formed from the polymeric components. The properties of the balloon and catheter formed from the polymeric material can be enhanced by crosslinking by irradiation of the polymeric material.

Balloons for medical catheters

A conductive polymer composition in which a particulate conductive filler is dispsered in a polymeric component which is a mixture of an essentially amorphous thermoplastic resin and a thermosetting resin. In preferred compositions, the amorphous thermoplastic resin and the thermosetting resin are substantially mutually soluble. In order to improve the thermal stability of the composition on exposure to successive thermal cycles, it is preferred that the composition be cured by heating the uncured mixture of amorphous thermoplastic resin, thermosetting resin, and particulate conductive filler at a rate of at least 15.degree. C./minute to the cure temperature.

Conductive polymer composition

A composition which contains 35 to 85% by weight of a copolymer of tetrafluoroethylene and hexafluoropropylene (FEP), 10 to 60% by weight of a copolymer of tetrafluoroethylene and perfluoropropylvinyl ether (PFA), and 5 to 60% by weight of melt-processable polytetrafluoroethylene (PTFE). The composition is particularly suitable for use as an insulating material on a substrate such as a resistive element in a conductive polymer heating cable. The composition has good physical properties, low creep, and low secondary crystallization, and exhibits little stress-cracking when exposed to elevated temperatures.

Fluoropolymer compositions

A conductive polymer composition in which a particulate conductive filler is dispersed in a polymeric component which is a mixture of an essentially amorphous thermoplastic resin and a thermosetting resin. In preferred compositions, the amorphous thermoplastic resin and the thermosetting resin are substantially mutually soluble. In order to improve the thermal stability of the composition on exposure to successive thermal cycles, it is preferred that the composition be cured by heating the uncured mixture of amorphous thermoplastic resin, thermosetting resin, and particulate conductive filler at a rate of at least 15.degree. C./minute to the cure temperature.

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Redwood City, CA, United States of America

Robert P Saltman