JOURNAL OF COMPOSITE MATERIALS Article Reinforcing of low-density polyethylene by cellulose extracted from agricultural wastes Shadi Sawalha 1 , Raed Ma’ali 2 , Omar Surkhi 2 , Mohammad Sawalha 1 , Bayan Dardouk 1 , Heyam Walwel 1 and Deema Haj Ahmad 1 Abstract Cellulosic materials were extracted from different agricultural wastes such as corn stalks, olive solid waste, and wood, by using a suitable extraction method. The extracted cellulosic materials were characterized using Fourier transform infrared spectroscopy. The produced cellulosic materials were used as reinforcements for low-density polyethylene to improve its tensile and thermal properties. A two-roll mill was used to mix the cellulosic materials (2.5–10 wt.%) with low-density polyethylene , and then the composite sheets were prepared by using a thermal press molding. The effects of filler type and its content on the mechanical and thermal properties were investigated by using the universal testing machine and differential scanning calorimeter, respectively. In general, with the increase of cellulosic materials content, there is an increase in the modulus of elasticity of the produced composites and a decrease of ductility. The ultimate tensile strength of the produced composites based on low-density polyethylene and cellulosic materials extracted from corn stalks and olive solid waste was found to be less than the tensile strength of low-density polyethylene, whereas the ultimate tensile strength of the composites based on low-density polyethylene and cellulose powder extracted from wood increased with increasing the cellulosic content. The addition of cellulosic materials was found to affect both the melting temperature of low-density polyethylene and its degree of crystallinity, depending on the cellulosic material source. Keywords Corn stalks, olive solid waste, wood, cellulose, elastic modulus, ultimate tensile strength, ductility, melting temperature, degree of crystallinity Introduction Agriculture produces significant amounts of wastes such as olive waste, wood and agricultural straws, which contain high quantities of organic matter. The agricultural wastes are causing pollution problems especially when they are burned or thrown in landfills. 1,2 Therefore, efficient utilization of such agri- cultural wastes is of great importance not only for mini- mizing the environmental impact but also for obtaining new materials that can be used in several applications. Recently, a more significant attention has been given to sustainable and biodegradable materials due to persist- ent discussions on the climate changes and regulatory demands underlining the need for clean environment and utilization of renewable resources. 1–4 Biomass includes a wide range of organic materials, which are composed of cellulose, hemicellulose, lignin and other compounds. 5 Recently, cellulose-reinforced composites have received much attention because of their light weight, nonabrasive, combustible, nontoxic, low cost and biodegradable properties. 6 Several studies have been carried out to investigate the effects of addition of cellulosic materials on the properties of various types 1 Chemical Engineering Department, An-Najah National University, Palestine 2 Materials Engineering Department, Al-Quds University, Palestine Corresponding author: Raed Ma’ali, Al-Quds University Faculty of Engineering, Jerusalem 51000, Palestinian Territory, Occupied. Email: rmali@staff.alquds.edu Journal of Composite Materials 0(0) 1–7 ! The Author(s) 2018 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0021998318781702 journals.sagepub.com/home/jcm