expansion of petroleum-based polymers. Despite trials of the reducing polymeric waste and strong restrictions concerning storage and product end-life cycle performance, the amount of the non-degradable polymer gradually has become ballast for the environment. Therefore, the endeavor of introducing biodegradable polymers in industrial-scale production gained ground among scientists [1]. The area of biodegradable material application is continuously extending thanks to their improving properties which in many cases resemble petrochemical polymers. In spite of many studies concerning the usage of biodegradable polymers, such as poly(lactic acid) (PLA) [2][3][4][5][6][7][8][9][10], poly(butylene adipate-co-terephthalate (PBAT) [11][12][13], polypropylene carbonate (PPC) [14][15][16], and starch [17][18][19][20], their commercial application is still not very common. Packaging industry appears as a branch which due to relatively low expectations towards mechanical properties allows for wide application of fully biodegradable polymers on a bigger scale [5]. The low thermo-mechanical stability of green composites, next to relatively high price, became their biggest disadvantage in comparison to petroleum-based non-biodegradable polymers [5,13]. Therefore, it is well founded to use recycled thermoplastic biodegradable polymers as a matrix for composites filled with organic and inorganic fillers [7,11].Except for the application of the specially prepared fiberlike natural fillers (e.g., bamboo, kenaf, jute and flax), great attention is placed on incorporation of agricultural waste materials into polymeric matrix [2,[21][22][23][24][25]. Extensive studies showed that presence of the natural fillers in biodegradable polymers may strongly accelerate biodegradation process thanks to faster hydrolysis followed by oxidation of both biopolymer, as well as the filler. Moreover, presence of natural filler increases water absorption, which highly influences biodegradation process of the composites, in comparison to neat polymer. In case of natural composites Abstract The aim of this study was to determine thermal and mechanical properties and applicability of ground chestnut shell waste as a filler for poly(lactic acid) composites. The used amount of filler was ranging from 2.5 to 30 wt%. Spectroscopic analysis of composites and its ingredients was conducted by means of FT-IR method. The mechanical and thermal properties of the composites were determined in the course of static tensile test, Dynstat impact strength test, DMTA analysis, and DSC method. The fractured surface morphology of biocomposites was evaluated by SEM analysis. Incorporation of the filler influenced the overall mechanical properties of the composites characterized by high stiffness and lowered impact resistance. Fabricated composites with different amounts of non-reactive natural waste filler exhibited acceptable mechanical and thermal properties. Therefore, these composites can be used as eco-friendly, biodegradable materials for low-demanding applications.
