Iran Polym J DOI 10.1007/s13726-016-0452-6 1 3 ORIGINAL PAPER Effects of different filler types on decay resistance and thermal, physical, and mechanical properties of recycled high-density polyethylene composites Mürs ¸it Tufan 1 · Selçuk Akbas ¸ 1 · Sema Yurdakul 2 · Türker Güleç 1 · Hasan Eryılmaz 3 Received: 1 September 2015 / Accepted: 12 June 2016 © Iran Polymer and Petrochemical Institute 2016 improved with the use of particleboard waste flour. The obtained results demonstrate that particleboard waste flour, such as wood-waste flour, is potentially suitable as a raw material in WPCs. Keywords Thermal properties · Water absorbtion · Decay resistance · Mechanical properties · Wood-plastic composites Introduction Due to global demand and increasing awareness of the environmental protection, the principles of sustain- ability are being actively pursued. Eco-efficiency involves research engaged in evaluating the recycling of waste materials, such as wood or agro-based (lignocellulosic) materials, plastics, and metals [1, 2]. In parallel with the increasing world population, the demand for both natural and synthetic products has been increased. Consequently, a substantial amount of waste material is being generated, thus resulting in environmental pollution. An evaluation of industrial recycling of environmentally polluting waste materials is particularly important [3]. One of the factors affecting the utilization of industrial woody waste materi- als is the environmental pollution caused by fossil fuels and the regulations imposed to control such emissions [4]. On the other hand, Turkey faces the problem of lack of woody raw materials by reason of its forested areas (21.6 million ha) that are unproductive by 46.7 % like the most of the countries [5]. Therefore, the utilization of waste materials, such as wood, carpenter, and particleboard, could benefit both environmentally and economically. Besides, they could be a potentially valuable resource for the manufacture of various materials and products. Three Abstract In this study, flexural properties, impact strength, thermal performance, water absorption, biological durabil- ity, and morphology of wood-plastic composites (WPCs) filled with different filler types were investigated. Six dif- ferent formulations of WPCs were fabricated from mix- tures of carpenter waste and recycled high-density poly- ethylene (R-HDPE). The carpenter waste was derived from wood and particle board wastes, and R-HDPE was used as the polymer matrix, with and without addition of maleic anhydrite grafted polyethylene (MAPE). All formula- tions were compression moulded in a hot press for 3 min at 170 °C. Investigations on the compression moulded specimens revealed that water absorption values in the par- ticleboard waste flour specimens were lower than in the wood-waste flour WPCs. However, the wood-waste flour- filled composites exhibited higher mechanical property val- ues than the particleboard waste flour WPCs. Statistically, only the wood-waste flour-filled composites with MAPE were significantly different. The use of MAPE (3 wt%) had a positive effect on the water absorption, crystallinity degree, and flexural properties of the WPCs. In addition, the peak temperatures of the composites did not show any variation, while thermal decomposition of the composites showed minor variations under the thermogravimetric anal- ysis. Furthermore, the decay resistance of the composites * Mürs ¸it Tufan mtufan35@hotmail.com 1 Department of Forest Industrial Engineering, Artvin Çoruh University, 08000 Artvin, Turkey 2 Department of Environmental Engineering, Süleyman Demirel University, 32260 Isparta, Turkey 3 Department of Environmental Engineering, Artvin Çoruh University, 08000 Artvin, Turkey