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...disposal of experts of materials for the specified cases, necessary for conducting comparative studies.

3. ADHESIVE TAPE STUDIES

(conducted by expert Bezrukov A.P.)

To answer the question of the decree, the expert examined pieces of colorless transparent adhesive tape (items 4.1, 4.2, 4.3, 4.6).
The answer to the question of the decree regarding the diagnostics and comparison of polymer film threads will be given in a separate expert conclusion.
Determination of the geometric characteristics (width and thickness) of the pieces was carried out using a ruler with a scale division of 1.0 mm and using an MK 0-25 micrometer with a scale division of 10 μm.
To determine the chemical composition of the materials, the method of molecular (IR spectral) analysis was used. Spectra were recorded on an IR-Fourier spectrometer model 1625 from the company "Perkin-Elmer" (USA) under standard equipment operating conditions. Preparation of samples for analysis was carried out according to standard methods for the study of adhesive tapes.
Upon visual inspection of the presented pieces of tape, it was established that the maximum width of their fragments with smooth parallel edges is 48 mm. The pieces of tape are significantly contaminated with silver-gray and brown substances, and are also deformed.
The studied pieces, cleaned of contaminants, are a colorless transparent adhesive tape consisting of a backing based on a polymer film material and a one-sided adhesive layer. The thickness of the backing is 30 μm.
When determining the chemical composition of this tape, it was shown that the base of its film backing is polypropylene, and the adhesive layer is a composition based on acrylic acid polyesters (acrylic resins).
The studied pieces of adhesive tape, in terms of structure, standard sizes (width and thickness of the backing), as well as chemical composition, correspond to adhesive tapes of foreign manufacture for packaging purposes. Tapes of this type can also be used for gluing various materials and products (paper, films, magnetic tapes, etc.).
It is not possible to conduct a comparative study of the discovered fragments of adhesive tapes with adhesive tapes found in Moscow at the addresses: ul. Borisovskie Prudy, d. 16, k. 2 and ul. Krasnodarskaya, d. 70, due to the lack of materials for the specified cases at the expert's disposal, which are necessary for conducting comparative studies.