Nanoparticles of carbides, nitrides and carbonitrides can be used to reinforce polymer matrix nanocomposites to obtain the required strength, hardness, corrosion and wear resistance. In order to efficiently achieve the desirable properties the polymer matrix and nanoparticles must be optimised. This paper reports on studies undertaken on TiC reinforced polymer matrix nanocomposites. The TiC nanoparticles were produced by sol-gel method and nanocomposites were obtained in situ, via the reaction and synthesizing of polyether-ester copolymer (PEE). TiC nanoparticles were characterised with a scanning electron microscopy (SEM) and the microstructure of the composites was examined by SEM and atomic force microscopy (AFM). Tensile properties were determined. For comparison, samples of polymer were also studied and composites with submicron size of TiC particles. The results, which are discussed in terms of size of the TiC particles, showed that the particles incorporated in the polymer matrix, influence the strength of the composites.