Chemical Modification of Polymers Intended to Increase Blood Compatibility

Abstract

Synthetic methods available for improving the haemocompatibility of polymer surfaces are outlined. The resent paper is concerned mainly with "passivation" techniques and some of the chemical routes by whict they may be effected Uses of isocyanatoeth I methacrylate as a functionalising reagent and for rafting to polymers are discussed with examples ,?its applications in the s ntheses of (a) monomers 8om a-amino acids and peptides, and the amino-sugars D-glucamine and d-lucosamine, and (b) macromers from pol (ether urethanes) and from the hydroxylic macromolecules po?y(ethylene glycol), poly(tetrahydrofuran), poYy(viny1 alcohol) and dextran.Grafting of monomers and macromers to functionalised olymers is considered. A series of grafts to polyurethane elastomers have been synthesised and tested) for blood-platelet adhesion (a measure of passivation) by a simple procedure which is outlined. All the graft copolymers tested show significantly reduced platelet adhesion compared to the base polyurethane. In particular, a Pellethane-poly D-glucamine graft is probably the most inert material towards platelets which we have examined. INTRODUCTIONAttempts to replace damaged or diseased parts of the body extend back over many centuries.