Polysiloxane-polyurethane block copolymers
Abstract
Abstract BLOCK-COPOLYMERS OF APOLYURETHANE AND A POLYSILOXANE HAVING DIRECT SILICON TO NITROGEN LINKAGES, A METHOD FOR THEIR FORMATION AND ARTICLES FORMED THEREFROM. THE COPOLYMERS ARE FORMED BY A CONDENSATION TYPE REACTION BETWEEN REACTIVE TERMINAL GROUPS OF THE POLYSILOXANE AND THE URETHANE-AMIDE GROUPS OF THE POLYURETHANE. INASMUCH AS THE REACTION INVOLVES ONLY THE AMINO GROUPS OF THE POLYURETHANE, BOTH POLYETHER AND POLYESTER URETHANES MAY BE USED. THE PREFERRED BLOCK-COPOLYMERS ARE THOSE HAVING A MINOR PORTIONOF POLY(DIALKYLSILOXANE) SEGMENTS AND A MAJOR PORTION OF POLYURETHANE SEGMENTS. THESE COPOLYMERS ARE CHARACTERIZED BY A HIGH DEGREE OF BLOOD COMPATIBILITY AND CONSEQUENTLY, ARE USEFUL IN PROVIDING BLOOD CONTACT SURFACES FOR DEVICES USED FOR DIRECT IMPLANTATION INTO THE BODY OR FOR EXTRACORPOREAL CIRCULATION OF BLOOD SUCH AS CIRCULATORY ASSIST DEVICES INCLUDING AUXILIARY VENTRICLES AND INTRA-AORTIC BALLOONS, AND VARIOUS TYPES OF BLOOD PUMPS.
Inventors
- 👤 Emery Nyilas
Bibliographic Details
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