Polymers are natural or man-made large molecules, often called macromolecules. They consist of smaller units, monomers, which react with each other to form a long chain similar to a string of beads. In my master's thesis, I researched the main polymers in global use, namely polyethylene, polypropylene, polyvinyl chloride, polystyrene, polytetrafluoroethylene and polyurethane. I researched their production, use and advantages and disadvantages. Recently, however, due to urgent action regarding plastic waste, bioplastics, i.e. polymers that are biodegradable or made from renewable resources, are increasingly coming to the fore. Bioplastics can mostly be prepared on the basis of starch, polylactic acid, polyhydroxyalkanoates, aliphatic-aromatic polyesters, cellulose or lignin. Depending on the type, bioplastics can offer improved circularity through the use of renewable (non-fossil) resources, a smaller carbon footprint, biodegradation as an alternative end-of-life option and improved material properties. However, compared to synthetic plastics, it has some inferior properties, is more expensive to produce, and also raises concerns regarding the leaching of monomers, oligomers and additives. In my master's thesis, I also investigated the teaching of polymers in secondary education, stating the main misconceptions of students and some advice for chemistry teachers. These include connecting the learning content to everyday life, using Johnston's triangle to present chemical concepts, clearly defining basic concepts and following the principles of effective learning in science. In addition to all of the above, experimental work is also very important, which promotes the student's understanding of the nature of science, which is why the master's thesis also presents a laboratory exercise on the subject of bioplastics.
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