## 5 PET Bottle Degradation Management Strategies
### Improving the Efficiency of Waste Management  
PET, as one of the most commonly used polymers for bottle production, is characterized by high strength and stability. However, these same properties make its degradation in the environment a long-term process [48]. As a result, its accumulation in ecosystems poses a significant environmental threat. Improper disposal of this material further exacerbates the problem, making it necessary to implement effective methods to reduce its negative impact on the environment.  
To reduce the amount of PET waste and improve its degradation, various approaches have been developed, including biodegradation, biological and mechanical recycling, chemical recycling, and upcycling. Each of these solutions aims to increase the efficiency of material reuse or accelerate its decomposition. The effectiveness of PET bottle recycling and  
\begin{table}
\begin{tabular}{l l l} \hline \hline
**Preventive Measure** & **Key Characteristics and Potential Drawbacks** & **Ref.** \\ \hline Proper storage and transport conditions & Avoiding high temperatures and sunlight due to their impact on PET stability. & [28,112] \\ Surface modifications with polyvinyl alcohol (PVOH) & Improves durability, limits oxygen permeability. & [113] \\ Surface modifications with MMA-MAc-DAM-MA & Limits oxygen permeability, too thick layer has adverse effect. & [114] \\ Hybrid coating with octavinyl-polyhedral & Surface more resistant to mechanical and chemical damage. Coating has good thermal stability. & [115] \\ oligomeric silsesquioxane & Protective layer of SiO\({}_{\text{x}}\) or hydrocarbon silicate & \\ Silicon-based coatings & applied to the inner side of the PET bottle. & [36,116,117] \\  & Reduced gas permeability, including oxygen. & \\  & PET surface modified by hydrogenated & \\  & amorphous carbon coatings or diamond-like & \\ Carbon coatings & carbon coatings. Enhancing gas barrier properties, & [35,118] \\  & surface more resistant to mechanical and chemical damage. Bottles may be recycled. & \\ TiO\({}_{2}\) nanoparticles coatings & UV protection, increased thermal stability. & [119] \\ Addition of UV stabilizers & Improves durability, reduces formation of carboxyl & [27] \\ (Tinuvin 1577w) & groups. & [27] \\ PET composites with & Improves mechanical properties, reduces UV & [120,121] \\ Ca\({}_{3}\)B\({}_{2}\)O\({}_{6}\) or CaB\({}_{2}\)O\({}_{4}\) & permeability. & [120,121] \\ PET composites with & Delays degradation but composite still generates polyurethane (PET-U) & [83] \\ \hline \hline \end{tabular}
\end{table}
Table 2: Summary of strategies for preventing PET bottle degradation.  
upcycling processes largely depends on the effective segregation and classification of waste by type of plastic. However, the segregation process poses significant technological and economic challenges, as many products contain various components and types of plastic, which significantly complicates their separation [46; 122]. [PERSON] et al. [123] emphasize that the quality of the input material, including the presence of contaminants or fragments of other polymers, has a significant impact on the final purity of the recycled PET. The effectiveness of recycling can be improved by implementing mono-collection systems, in which only food-grade PET bottles are selectively collected. This solution provides better results than co-collection systems [124]. Additionally, the use of artificial intelligence (AI) in the sorting process allows for precise identification and removal of non-PET containers from the recycling stream, significantly improving the efficiency of segregation and the quality of the obtained rPET [46].