From Thermal Degradation of Polymeric Materials

Thermal degradation of polymeric materials is an important issue from both the academic and the industrial points of view. The analysis of the degradation process has become more and more important as a result of an increase in the range of temperatures for engineering applications, recycling of post-consumer plastic waste, as well as the use of polymers as biological implants and matrices for drug delivery, where depolymerisation is an inevitable process affecting the lifetime of an article. Thermal degradation of polymers is therefore of paramount importance in developing a rational technology of polymer processing, higher-temperature polymer applications, polymer usability, storage and recycling, in addition to understanding the thermal decomposition kinetics and mechanisms for optimum synthesis of long-lasting fire-safe polymeric materials.

Unfortunately, thermal degradation is likely to be responsible for serious damage to any polymeric material and this effect is especially important for recycled polymers, as they suffer successive cycles of high and low temperatures. Controlling degradation requires understanding of many different phenomena, including the diverse chemical mechanisms underlying structural changes in macromolecules, the influence of polymer morphology, the complexities of oxidation chemistry, the intricate reaction pathways of stabiliser additives, the interaction of fillers and other additives together with impurities, and the reaction diffusion processes that often take place. Furthermore, there exist substantial differences between pure and industrial polymers that may have detrimental effects on the thermal degradation of polymeric materials, and this increases the complexities of the thermal degradation of polymers.

Thus, thermal degradation is an extremely complex and important process...

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Topics of Interest

[a.1] N.S. Allen and M. Edge, Fundamentals of Polymer Degradation and Stabilisation, Elsevier Applied Science, London, 1992, 1. [a.2] W. Schnabel, Polymer Degradation Principles and Practical...

4.1 Introduction Generally, the thermal degradation of a polymeric material follows more than one mechanism. The existence of more than one concurrent chemical reaction accompanied by other physical...

Overview Degradation of polymers includes all the changes in the chemical structure and physical properties of the polymers due to external chemical or physical stresses caused by chemical reactions,...

Depolymerisation and statistical fragmentation of chains are generally the two different mechanisms of degradation of polymers. The rate and extent of degradation may be monitored by changes in a...

Overview Owing to the nature of polymer processing (mainly casting, injection, extrusion or moulding), deteriorative reactions occur at this early stage when polymers are subjected to heat and...