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Polymer degradation can be significant in these cases and, in practice, is often only held back by the use of advanced polymer stabilizers. Degradation arising from the effects of heat, light, air and water is the most common, but other means of degradation exist. The in-service degradation of mechanical properties is an important aspect which ...
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] It is the most significant factor in the weathering of plastics. [2]
Aerobic degradation occurs gradually at room temperature, but almost all polymers are at risk of thermal-oxidation when they are processed at high temperatures. The molding or casting of plastics (e.g. injection molding) require them to be above their melting point or glass transition temperature (~200-300 °C). Under these conditions reactions ...
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 ...
Polymer physics is the field of physics that studies polymers, their fluctuations, mechanical properties, as well as the kinetics of reactions involving degradation ...
The most common sources of polymer embrittlement include oxygen in the air, water in liquid or vapor form, ultraviolet radiation from the sun, acids, and organic solvents. [15] One of the ways these sources alter the mechanical properties of polymers is through chain scission and chain cross-linking.
Once implanted, a biodegradable device should maintain its mechanical properties until it is no longer needed and then be absorbed by the body leaving no trace. The backbone of the polymer is hydrolytically unstable. That is, the polymer is unstable in a water based environment. This is the prevailing mechanism for the polymers degradation.
Polymer degradation is a change in the properties—tensile strength, color, shape, or molecular weight—of a polymer or polymer-based product under the influence of one or more environmental factors, such as heat, light, and the presence of certain chemicals, oxygen, and enzymes.