LAUSR

Purpose. Development of methods for determining the degree of drawing, at which the transformation of the unoriented structure of the polymer sheet (geomembrane) into a highly oriented one begins, which increases its strength, and, thereafter, the durability in the process of gold extraction by heap leaching. Methodology. The theoretical method for the investigation of the stress­strain state of a polymer sheet in the pro­ cess of drawing on the basis of previously obtained experimental data. findings. The following has been developed: the model of the supramolecular spherulitic structure of amorphous­ crystalline polymers in a non­oriented and oriented states; the method for determining the degree of drawing at which the destruction of the spherulitic structure of the polymer material begins. originality. For the first time, the problem of changing the stress­strain state of a polymeric material during its orientational drawing was solved by an analytical method. The developed mathematical model allows predicting the elastic properties of oriented amorphous­crystalline polymers of a spherulitic structure, which makes it possible to increase their strength in the desired direction. Practical value. On the basis of theoretical studies, as well as the results of previously conducted experimental studies, a method was developed for determining the degree of drawing at which the destruction of the spherulitic structure of a polymeric material begins and a fibrillar structure is formed. This technique can be used while designing the equipment for the orientation of sheet polymer materials that are therefore used for strengthening polymer sheets (geomembranes), used for gold extraction by heap leaching. keywords: geomembrane, polymer, structure, orientational drawing, stress, strength