The liquid-liquid equilibrium constant for acetic acid in a quinary system olive oil-epoxidized olive oil-acetic acid-hydrogen peroxide-water was experimentally determined for temperatures and component ratios relevant for in situ epoxidation of plant oils. The values have the constant range from 1.52 to 2.73. To predict the equilibrium constant for acetic acid, the experimental data were correlated with UNIQUAC (universal quasi chemical) and NRTL (non-random two liquid) activity coefficient models. For simplified calculation of the phase equilibrium the insolubility of olive oil and epoxidized olive oil in the water, as well as insolubility of water and hydrogen peroxide in the olive oil and epoxidized olive oil, was assumed. The root mean square deviation (RMSD) of the experimental and calculated values of the liquid-liquid equilibrium constant for acetic acid is 0.1910 for the UNIQUAC model and 0.1815 for the NRTL model. For rigorous flash calculation, when the partitioning of all components between the phases was assumed, the RMSD for the NRTL model is 0.1749.

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A world without plastics, or synthetic polymer materials, seems unimaginable today. During the last decade, the share of synthetic polymer consumption used in packaging industry increased to 42%, in relation to the total consumption of polymers. Wide use of polymer materials leads to generation of large amount of waste. Environmental pollution, as well as alarming reduction of fossil fuels have led to the implementation of the strategies for pollution control, pollution prevent, energy and resources saving. Growing awareness of global pollution consequences has rised these concerns on the level of the Green Chemistry concept. Green Chemistry is a multidisciplinary field where chemistry science and industry meets each other in order to design products and strategies for elimination of harmful substances. It is well known that the most important primary sources of feedstock for polymer materials production are fossil fuels. Increasing demand for polymers, has imposed the need for fossil fuels replacement by renewable resources for its synthesis. In this paper we have shown the implementation of the Green Chemistry principles in the synthesis of packaging material based on polylactide (PLA). Polylactide is one of the most promising polymers because of its biocompatibility, biodegradability and the fact that it can be produced from the biobased feedstocks. In accordance with modern ecological requirements, packaging material should be degradable or biodegradable and also economic. The use of PLA has a growing trend, therefore, today it takes an important place in packaging industry, especially because the properties of PLA films are comparable to standard petroleum based flexible packaging materials. The main purpose of this study was to synthese packaging material based on polylactide by microwave synthesis as a method which implement some of the Green Chemistry principles. Microwave synthesis of PLA meets requirements of biobased polymers from the aspect of energy and time saving production of this biodegradable material. The microwave-assisted synthesis of PLA provides homogenous heating of reaction mixture, significant reduction in polymerization time, decreased consumption of organic solvent and, in the same time, high molecular weight polymers.

Interdisciplinary approach in education attracts significant attention in the contemporary education due to its beneficial effect on teaching-learning process. It is noticed that interdisciplinary approach help students in developing knowledge, increases problem solving skills, supports self-confidence and passion for learning. In this work we explained interdisciplinary approach that was based on mathematics, as a school subject and materials science as a scientific discipline. The combination of the two disciplines is not usual, since materials science is not part of middle school curriculums, even though it is known as an interdisciplinary field that combines many aspects of science and provide results important for everyday life. Polymers, adhesives, coatings, rubbers, ceramics, solar cells are widely used in every day, but they are rarely explored in the classroom. The main reason is that problems in materials science are highly advanced, but with the careful planning there are many possibilities to make them understandable to students. In this work we selected different problems from the materials science field which could help students to develop their modeling competences, since many problems relate to the mathematics. The examples have been derived from the practice applied with students from 10 to 18 years. They illustrate connection of materials science to school mathematics in order to enrich educational process. Educational process benefits in many segments, from developing students' knowledge to promotion of scientific disciplines and jobs in the field of science. Examples show how authentic context support students' engagement and their learning become meaningful and purposeful. Also, we highlight the different perspectives explored during the interdisciplinary approach and stress development of critical thinking skills during researching across disciplinary boundaries. That increase transfer of student knowledge trough disciplines and give them wider prospective of knowledge that they gain in the regular lessons which lead to creativity and production of new ideas. Examples follow elements that are common for interdisciplinary approach of instructions recommended by Fink taxonomy for significant learning. Those elements are foundational knowledge which assume understanding ideas, application of skills, integration and connection of ideas, human dimension and caring, and learning how-to learn which is important for obtaining insight into process of learning. Those instructions are leading to meaningful and lasting experiences for students and fully illustrate importance of school mathematics in scientific disciplines such as materials science.