Composite material and its method of production

A process for producing a composite material comprising a first segment covalently bonded to a second segment by a urethane and optionally a urea and/or an amide linkage, wherein the first segment is a carbon nanoparticle moiety and the second segment is a polyol moiety, the process comprising a first step of polymerising (i) a functionalised carbon nanoparticle, (ii) a polyol, (iii) a compound comprising at least two isocyanate groups, and optionally (iv) a chain extending compound comprising at least two chemical groups selected from the group consisting of a primary amine, an hydroxyl and a carboxylic group, wherein functionalised means functionalised with any one of carboxylic acid, tertiary alcoholic, epoxide, primary alcoholic or primary amino groups.