Polyvinyl chloride is nowadays one of the most widespread thermoplastic polymers. Pure PVC is solid brittle material, however it can be modified with additives which make it more prone to processing and moulding. Plasticizers represent the most important group of those additives and are used to soften it and reduce glass transition temperature. During the lifetime of PVC, the degradation processes take place, which include elimination of HCl and migration of plasticizers. Migration occurs through two processes: as diffusion through the polymer to its surface and evaporation to the surrounding gas phase. The loss of plasticizers results in yellowing, sweating and shrinking of PVC, while they crack because of changes in specific volume. Museums and galleries identified that as a problem as they want to conserve their PVC collections and artifacts in their original state. However, those processes are not thoroughly researched yet and clear guidelines on conservation of PVC objects don’t exist yet. That is why I studied migration and loss of plasticizers in PVC. I thermally degraded samples, which were plasticised by different plasticizers, at different conditions to determine the effects of temperature, relative humidity and type of plasticizer. I used extraction and GC-FID to determine the content of plasticizers in samples. I can conclude that relative humidity does not affect migration, while higher temperatures corelate with higher losses of plasticizers. Additionally, the type of plasticizer plays an important factor, as migration is slower if the molecular mass of plasticizer is higher. During my work I also researched if the detected mass loss can be attributed only to the loss of plasticizers. I concluded the mass loss is always higher than the loss of plasticizers, which means plasticizers are not the sole compound that was lost in the process of degradation.
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