Degradation of PLA/hemp and PLA/jute composites B. Szaraniec * , T. Goryczka ** * AGH – University of Science and Technology, Faculty of Materials Science and Ceramics, Department of Biomaterials, 30-059 Krakow, al Mickiewicza 30, Poland ** University of Silesia, Institute of Materials Science, 40-007 Katowice, Bankowa 12, Poland Abstract The influence of the type of fiber reinforcement (hemp or jute fibers) on bio- and hydrolytic degradation process was studied. Composites with polylactide (PLA) matrix contained 5 wt. % of hemp or jute fibers were prepared by injection moulding and marked as the PLA/hemp and PLA/jute, respectively. Samples in the shape of a paddle were composted or soaking in water for 15 weeks. During the process mechanical properties were controlled. After three weeks, the value of such properties as tensile strength and elongation-at-break significantly decreased for the PLA/jute composite, whereas in PLA/hemp they remained comparable that measured for pure PLA even 9 weeks of the treatment. In comparison to pure polylactide the fiber reinforcement made the degradation process easier than in pure PLA. Polylactide and its composites (PLA/hemp and PLA/jute) were more sensitive to hydrolytic degradation than biodegradation. Introduction Polymers derived from petrochemical raw materials, which do not decompose under natural conditions, are serious burden for an environment. Commonly used goods, as disposable, are recycled in small percentage and mostly find their way to landfills, where stay for years. For these materials, degradable plastics derived from renewable raw materials can be an alternative. One of the examples of such materials can be polylactide (PLA), which is known from its application for manufacturing of short life products. That’s why it becomes a common massive thermoplastic material [1]. Microbiological degradation of polylactide is caused only by selected bacteria strains and proceeds relatively slowly especially at lower temperatures [2,3]. The speed of the process can be appropriately adjusted by an introduction to polymer other biodegradable materials such as natural fibers [4]. The presence of natural fibers modifies the properties of such composite [5]. The first of all, it facilitates colonization of soil microorganisms in the biologically harder degradable polymers. Additionally, it increases the surface roughness and make easier occurrence of the degradation. Mainly, degradation rate in polymer depends on the surface condition. Polymer with rough surface undergoes easier to degradation than one with lower roughness [6].