Speaker
Description
In the course of this research for the development of the paper, hydrogel samples based on raw whey and gelatin were obtained. Plasticization was achieved by adding glycerin, and crosslinking was achieved using copper. To confer antimicrobial properties, metallic copper was generated in situ through a reaction between copper sulfate and ascorbic acid, the latter being used as a reducing agent. The gel samples were created under conditions of excess copper sulfate, necessary for the crosslinking process, with varying concentrations of the reducer. These were poured into silicone molds and dried for 48 hours, then stored in the refrigerator. Absorption tests were conducted using the tea bag method. For this purpose, pieces of hydrogel with surfaces of approximately 5 cm² were inserted into envelopes made from non-woven synthetic material. Before the absorption process, the envelopes were moistened in distilled water, blotted with dry paper, and weighed. The degree of absorption was calculated based on the increase in mass of the hydrogels over a period of 96 hours. Measurements were initially made every 5 minutes, then every 15 minutes, and towards the end of the process, once every 24 hours. Fick's and Schott's equations were applied to analyze the kinetics of absorption. The results show that initially, water absorption followed Fick's model, but over the entire duration of the process, the absorption adhered to Schott's model. The stability of the hydrogels was investigated by repeating the absorption process four times, with the samples being air-dried for three days between cycles. Repeated tests have shown that the hydrogels are stable for at least four successive cycles of absorption.
