The preparation of new cellulose fiber reinforced thermoplastics is described, and the mechanical properties and water absorption of these materials are measured. In order to improve the compatibility between cellulosic and plastic materials, different amounts of coupling agents, such as organotitanate compounds, maleic anhydride copolymers and their combinations, are studied. As a filler, pine fiber, rose, carnation or coffee husk is used. Furthermore, the influence of the composition of the composites and the particle size of the filler on the material properties of the thermoplastics are investigated. The surface of the fractured samples is analyzed using scanning electron microscopy (SEM). (C) 2003 Wiley Periodicals, Inc.