Biobased polyamide reinforced with natural fiber composites

Abstract Polyamides, also known as nylon, are polymer families with high-performance properties, usually encompassed in the group of “engineering polymers”. Some of the properties to highlight are its high mechanical strength and modulus, chemical resistance, and thermal stability. Furthermore, polyamides are recyclable. Among the most industrially used polyamides, PA6, PA6.6, and aramids stand out. Nonetheless, these materials are oil-based, a perishable resource. Thus, there is much interest in bio-based polyamides. These BIO-PA have been in the market for some time. PA11 and PA10.10 are clear examples of such materials. The preparation of composite materials based on BIO-PA matrices with synthetic reinforcements shows low complexity. However, the use of natural reinforcements limits the processing temperatures due to the degradation of celluloses. This chapter reviews the different biobased polyamides, its properties, and its production technologies. The chapter summarizes the mechanical and thermal properties of a polyamide 11 composite reinforced with stone ground wood fibers. The composites show promising properties, in line with commodity materials like glass fiber reinforced polypropylene. PA11 shows chemical compatibility with the natural fibers, avoiding the use of coupling agents to obtain strong interphases.