Wool fiber-reinforced thermoplastic polymers for injection molding and 3D-printing

The authors describe the state of the art in research and development in thermoplastic wool fiber-reinforced composites in the present book chapter. In the beginning, wool and horn's structural property relationships as keratinous, natural composites are summarized. This comparison's main objective is to show the potential of keratinous composites and highlight the unique circumstances that need to be taken into account in the development and manufacture of wool fiber-reinforced composites. The published papers in the field of wool fiber-reinforced thermoplastics are critically evaluated and classified according to the thermoplastic material and processing technique based on comprehensive literature research. The achieved properties, depending on the processing methods, are compared and used to describe the micromechanics and the fiber–matrix interaction of wool fiber-reinforced composites. The opportunities and limitations of adhesion promotion to improve mechanical properties are discussed by analyzing literature studies. In this chapter, properties such as combustibility and biodegradation of wool fiber-reinforced composites are critically evaluated. In addition to the literature research analysis, own results for injection-molded and 3D-printed wool/polymer composites are presented. With the help of existing data, suitable products and possible market segments for wool fiber-reinforced thermoplastic polymers are identified. The chapter ends with a final critical evaluation of the state of research. Finally, ideas for necessary future research and development work are presented.