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In polymers, such as plastics, thermal degradation refers to a type of polymer degradation where damaging chemical changes take place at elevated temperatures, without the simultaneous involvement of other compounds such as oxygen. [1] [2] Simply put, even in the absence of air, polymers will begin to degrade if heated high enough. It is ...
Thermal degradation affects the entire bulk volume of the polymer making up an object, and is strongly affected by the temperature and amount of light exposure. [ 14 ] Ozone -induced degradation will deteriorate saturated and unsaturated polymers when the plastic is exposed to atmospheric ozone. [ 14 ]
Polymer degradation is the reduction in the physical properties of a polymer, such as strength, caused by changes in its chemical composition.Polymers and particularly plastics are subject to degradation at all stages of their product life cycle, including during their initial processing, use, disposal into the environment and recycling. [1]
These particles originate from the degradation of larger plastics and are now found in various environmental matrices, including water, soil, and air. Given their minute size, nanoplastics can penetrate biological barriers and accumulate in human tissues, potentially leading to adverse health effects. [3] [4]
If the residence time and/or melt temperature (temperature at melting) are too high, then thermal degradation or thermooxidative degradation will occur resulting in discoloration and reduced molecular weight, as well as the formation of acetaldehyde, and the formation "gel" or "fish-eye" formations through cross-linking.
Thermal treatment of municipal waste can involve the depolymerization of a very wide range of compounds, including plastics and biomass. Technologies can include simple incineration as well as pyrolysis, gasification, and plasma gasification. All of these are able to accommodate mixed and contaminated feedstocks.
The Relative thermal index (RTI) is a characteristic parameter related to the ability of plastic materials to resist thermal degradation. The RTI is part of the longterm thermal aging program (LTTA) described in the UL 746B standard from UL .
This plastic bucket has been used as an open-air flowerpot for some years. Photodegradation has made it brittle, causing part of it to break off when the bucket was moved. In polymer chemistry, photo-oxidation (sometimes: oxidative photodegradation) is the degradation of a polymer surface due to the combined action of light and oxygen. [1]