Medical balloons are useful for many endovascular treatments including dilatation of a body vessel, and drug delivery, and expansion and seating of a medical device such as a stent. Medical balloons may be made of a single layer of material or of multiple layers of material. In the case of multi-layer or composite balloons, the multiple layers within the composite may be different materials to obtain a blend of physical or chemical properties to optimize performance in some particular way(s), depending on the application.
Expanded polytetrafluoroethylene (ePTFE) is of interest for use in medical balloons because of its low coefficient of friction, chemical resistance, porous microstructure, flexibility, and strength. Because of the physical properties of ePTFE, however, the material cannot be processed in the same way that conventional thermoplastic elastomers are processed. In particular, adhering ePTFE to other materials is difficult because it has a low surface energy and a very high melt viscosity. New composite materials with ePTFE and ways of making said composites can be beneficial.