Catheter tubing of controlled in vivo softening

摘要

A catheter tubing has a layer of a hydrophobic stiffening polymer encapsulated by a layer of hydrophilic thermoplastic base polymer. Preferred stiffening polymers are polyesterpolyether block copolymers. Preferred base polymers are thermoplastic polyetherurethanes. The encapsulated layer may be a stripe or an annular layer having base polymer layers laminated on both surfaces thereof.