| Abstract [eng] |
The aim of this work is to produce coatings suitable for regulating the solubility of fertilizers. The master 's thesis examines the technology of slow – release fertilizers, produced four different coatings suitable for regulating the solubility of fertilizers and provided technological recommendations to produce slow – release fertilizers. The development and classification of slow – release fertilizers, materials used in coating production, synthesis and properties of different coatings are discussed in the literature review. The research part describes the materials used, the physical, chemical, and instrumental methods used in the work. The optimal amounts of polyvinyl alcohol, glycerol, starch, and molasses required for the synthesis of coatings were determined. Investigations of the swelling, moisture sorption, the influence of coatings on the solubility rate of fertilizers and biodegradability were performed. From the obtained results it was established that the produced coatings are stable and suitable to produce slow–acting fertilizers. By varying the thickness of the coatings and modifying them with glycerol, starch and molasses, the time and duration of nutrient release can be regulated. The principal technological scheme recommended to produce slow – release fertilizers is in the in the technological part. Workers’ safety and health requirements are discussed. Work size – 73 pages. It consists of lists of tables and figures, list of abbreviations, introduction, literature review, research part, technological recommendations, occupational safety and health, conclusions, list of used literature and annexes. The results of experiments are listed in 2 – 6 tables, 12 – 42 figures and 5 appendices (13 tables, and 1 figure). |
