## 1 Introduction  
Energy demand and costs for heating during winter and cooling during summer are very high. Building insulation can reduce these expenses, which is why its use is becoming more and more important. Due to the increased use, the production of suitable materials is just as important. Insulation materials are usually produced from inorganic materials, even though some of those materials have been prohibited due to the suspicion of health risks in the past. Furthermore, these materials do have a high impact on the environment. This is why it is important to investigate insulation materials based on organic materials. In addition to that, large quantities of agricultural residues are available. Those residues from agricultural production have a high potential to be used as alternative for some inorganic materials, such as particleboards. With regard to the regional availability of the materials and the resulting 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 lignocellulosic 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]. [PERSON] 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 to fabricate strawboards. For wood-based particleboards, urea-formaldehyde (UF) has been the essential adhesive. Also, for the production of particleboards from eggplant stalks, UF is technically viable as an adhesive [9]. [PERSON] et al. [10] investigated the influence of varieties of starch (cornstarch, cassava starch, potato starch) on flexural properties of composites. According to [10], composites based on cornstarch had higher flexural strength and flexural elastic modulus. Particleboards and their properties have already been researched in numerous previous investigations, in which the improvement of the mechanical properties through modification of resin content, particleboard density, and straw treatment could be identified. The mechanical properties of particleboards made of mesquite, salt cedar, and date palm, for example, were improved as the UF resin content increased from 9 to 11% [11]. In [12], the qualities of the particleboard improved when the content of UF resin increased from 7% to 16%. The mechanical properties of the saline Jose tall wheatgrass (JTW) particleboards improved with the increase of particleboard density from 0.71 to 0.75 g/cm\({}^{3}\)[13].