Polymers are divided into thermoplastic polymers, thermosetting polymers and elastomers. Elastomers are mainly used because of the elastic properties, which ensures a reversible deformation. Elastomers also include natural rubber, from which the rubber is made. Due to the cross-linking, the possibility of rubber recycling and its reuse is limited. Waste rubber is then deposited in the landfill.
In diploma, I write about the devulcanization process that would attempt to regain the properties of the raw material - the unvulcanized rubber compound. Devulcanization is a process in which we try to break the chemical bonds between the polymer chains, resulting from the vulcanization process, by various techniques and additives. Different types of devulcanization processes are described: mechanical, chemical and biotechnological. Selected examples of specific devulcanization methods are analyzed in detail. In the case of mechanical devulcanization, the process is carried out at a high temperature and high pressure, while in the case of chemical devulcanization, where waste rubber is added to various chemical compounds that allow the splitting of bonds between the polymer chains. Biotechnological devulcanization is the least researched method of devulcanization in which microorganisms decompose bonds by oxidation.
In the thesis, I write about different types of devulcanization processes and reuse of devulcanized rubber. I compare properties (tensile strength, elongation at break) between vulcanized rubber (made of natural rubber) and vulcanized rubber, made of natural rubber and devulcanized rubber. Examples of the reuse of devulcanized rubber are also presented.
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