Construction materials have a direct impact on the environment, on people, and their health. In addition, building insulation plays a decisive role in terms of energy consumption of buildings and regarding CO 2 -emissions over their whole life cycle. In order to achieve a holistic concept for green building worldwide, it is necessary to develop ecological insulating materials and to scientifically examine them in terms of their technical properties, as done with particleboards from agricultural waste presented in this article. This study aims to characterize the properties' tensile and compressive strength, modulus of rupture (MOR), and elasticity (MOE) and thermal conductivity of particleboards affected by parameters, such as waste type (rice straw or flax shives), particleboard density, resin type, and content, as well as the use of treated rice straw. Particleboards made from flax shives had superior properties compared to the rice straw particles. The mechanical properties of the boards increase with an increasing resin content, except for the MOR and MOE, which decrease with an increasing resin content, and reach their peak value at a resin content of 10%. Appl. Sci. 2019, 9, 3878 2 of 20 ecological footprint, numerous studies on organic based insulation materials have already been carried out by researchers with materials such as sheep wool, straw, cotton, and flax for Austria and the Czech Republic [1][2][3]. Rice is the primary food for more than 40% of the world's population. Every year, 596 million tons of rice are produced, resulting in 570 million tons of rice straw worldwide [4,5]. Currently, 12 million MTs of rice straw are produced yearly in Egypt [6]. This quantity is the reason why rice production has a high impact in Egypt and this rice straw, as a residue of this production, poses a serious problem for the farmers involved. Rice straw is conventionally cleaned, burned, or used for temporary heating purposes. This current practice causes serious environmental problems. But rice straw is a renewable resource that can be used as raw material for the production of insulated particleboard. A particleboard is a sheet product manufactured under pressure from particles of wood or other lignocellulose materials by adhesive [6]. With the increasing demand for particleboards, the demand to provide alternatives with renewable and ecological materials is accordingly growing. This research will use rice straw as alternative to fill this gap.The principal chemical composition of rice straw is 28-48% cellulose, 12-16% lignin, 15-20% ash, and 9-14 silica. The fiber length is between 0.4-3.4 mm with an average value of 1.4 mm, and the fiber width is from 4-16 mm, with an average value of 8 mm [7].Tong et al. [8] found that straw shows numerous positive properties, such as low density and a renewable nature. Rice straw is an annually renewable agricultural waste. Particleboard performance depends on the properties of adhesives and their compatibility with fibres. Several kinds of adhesive resins have been used...
