The master's thesis focuses on understanding organic nitrogen compounds such as amines, alkaloids, amides, imines, imides, hydrazines, and hydrazones. These compounds play a significant role in comprehending the compounds and chemical reactions involved in the use of hair-dressing products. The thesis provides a detailed explanation of hair structure, the theory of oxidative coloring, hair bleaching, natural hair color, and permanent hair transformation, thereby facilitating the understanding of chemical processes. The primary objective of the experimental part of the master's thesis was to prepare pigments of para-phenylenediamine and ortho-phenylenediamine and utilize them to create oxidative hair dye. The intensity of hair coloring was then compared between the oxidative hair dye prepared from both pigments. It was found that the oxidative hair dye derived from ortho-phenylenediamine pigment exhibited greater intensity. The second part of the experimental work was didactic. Based on the research conducted in the thesis, a guided experimental research project titled "Exploring the Secrets of Hair Color Durability" was prepared for students. This part consisted of two sections, each with its own research question. Through conducting experiments, students confirmed or refuted their research hypotheses. In the first part, students determined the pH value of the oxidative hair dye, hydrogen peroxide, and the mixture of oxidative agent and dye. They examined the influence of temperature on the stability and effectiveness of oxidative hair dyes and identified colors using thin-layer chromatography (TLC). They also studied color degradation caused by different concentrations of hydrogen peroxide and the change of color in oxidative hair dyes at various pH values. In the second part, students produced natural hair dyes following a specific procedure and prepared oxidative hair dye of identical shades. They then compared the intensity of hair coloring and investigated the impact of elevated temperature and time on the stability of color of samples of natural hair. The experiments in the didactic part were designed to cover the learning objectives outlined in the chemistry curriculum for high schools.
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