A method of preparing particles of a lignocellulosic material for the manufacture of a finished product, such as a particle board, includes the steps of chemically modifying the lignocellulosic material by impregnating the lignocellulosic material with a suitable anhydride in a non-aqueous solvent; applying to the particles of lignocellulosic material an adhesion promoter to promote the adherence of a thermoplastic resin to the surfaces of the particles of lignocellulosic material; and applying to the particles a thermoplastic resin in dry powder form, so that after the application of the adhesion promoter, the thermoplastic resin adheres to the surfaces of the particles of lignocellulosic material, the thermoplastic resin having been surfaced modified by irradiation or by fluorination; and removing any solvent present.