Виявлення впливу модифікації поверхні картону розчином гідроксихлориду алюмінію на показники крайового кута змочування та поверхневої енергії

This study investigates the process of cardboard surface modification with an aqueous solution of Al2(OH)nCl6–n and its effect on the indicators of contact angle and surface charge of dissolved substances in cardboard for the manufacture of packaging and disposable tableware. The task addressed relates to the lack of a technological approach to modifying the surface of cardboard, which would simultaneously enable high adhesion between cardboard and polymer by controlled change in wettability and surface energy without loss of its barrier properties. A solution option is to improve the technology of modifying cardboard for the production of disposable tableware with an aqueous solution of Al2(OH)nCl6–n The experimental studies involved manufacturing a series of cardboard samples with different compositions, determining the contact angle by the lying drop method and the surface charge of dissolved substances. The effect of surface treatment on the indicators of the contact angle and surface charge of dissolved substances of cardboard for the manufacture of packaging and disposable tableware has been established. It was found that the contact angle decreases to 82.8–84.7° compared to 91.8–93.4° for unmodified samples (without applied polymer) and 116.1–116.6° versus 112.1–115.9°, respectively, for samples with a polymer coating. At the same time, the surface charge of dissolved substances increases from –18.3–25.9 to –51.3–54.1 μg-equiv./l, that is, by 2–3 times. The results indicate that the treated cardboard samples have better wettability. This property will contribute to better contact between the cardboard surface and the polymer melt during its application and subsequent gluing of the structural elements of an article. The proposed approach to modifying the cardboard sheet is promising for further implementation in industrial processes, in particular to produce packaging materials and disposable tableware. This will make it possible to influence the barrier properties of the finished cardboard paper, as well as to improve the functional properties of packaging and disposable tableware made of modified cardboard