Creation of a composite material based on plant components

Introduction. The study is aimed at analyzing the possibility of creating a building composite material based on amylose and amylopectin with the introduction of crushed walnut shells as a filler. Materials and methods of research. To obtain the composite, the following components were used: distilled water, potato starch (NevaReaktiv, St. Petersburg, Russia), acetic acid 70% (NevaReaktiv, St. Petersburg, Russia), highly dispersed walnut shell powder. For this research, we used walnut shells of the Chandler variety (engrafted) collected form the Belgorod region. The composite was produced in several stages. At the first stage, a mixture of starch and walnut shells was added to distilled water, followed by a pre-prepared 9% acetic acid solution. The resulting mixture was thoroughly mixed, after which it was transferred to a stainless-steel bowl and subjected to heat treatment. The resulting mixture was then pressed with solid-phase compaction method at a pressure of 72 MPa. We studied the physical and mechanical characteristic of the resulting composite, its thermal properties, as well as the hydrophobic-hydrophilic balance of the surface. Results and discussion. The resulting composite has good strength characteristics. Flexural strength at break is σf = 25.85±2.51 MPa and σf = 28.44±5.71 MPa for filling 50% weight and 75% weight. Accordingly, they put it on a par with similar composites made from more conventional thermo- and thermoset polymers. The temperature limit for the composite material exploitation has been established, the upper of which can be considered the temperature at which the polymer matrix begins to soften - 103.1 °C.