الملخص

          In this paper, polymeric compounds were prepared from unsaturated polyester as a base material with sisal fibres with different weight percentages (1%, 2%, 3%, 4%, 5%) as a reinforcing material. After comparing the unsaturated polyester before and after reinforcement of the prepared compounds, it was found that there is an increase in the values ​​of mechanical properties (Hardness strength, Compressive strength, Tensile strength, Impact strength) when reinforced by weight (4%) at room temperature; however, when treated at temperatures  (8.55) ℃, it was found that the hardness, compressive and tensile strength decrease when heat treatment is at (8.55) ° C,  the impact strength increases at higher temperatures and decreases at lower temperatures. It was also found that the thermal conductivity decreased at all temperatures (8.55)℃, which indicates that the polymeric composites consisting of unsaturated polyester resin reinforced with Nylon 66 are good heat insulators.