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The onset of thermal degradation dictates the maximum temperature at which a polymer can be used. It is an important limitation in how the polymer is manufactured and processed. For instance, polymers become less viscous at higher temperatures which makes injection moulding easier and faster, but thermal degradation places a ceiling temperature ...
In comparison to simply incinerating the starting polymer, depolymerization gives a material with a higher heating value, which can be burnt more efficiently and may also be sold. Incineration can also produce harmful dioxins and dioxin-like compounds and requires specially designed reactors and emission control systems in order to be performed ...
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 limits the applications of these materials. Polymer degradation caused by in-service degradation can cause life threatening accidents.
In materials science, a thermosetting polymer, often called a thermoset, is a polymer that is obtained by irreversibly hardening ("curing") a soft solid or viscous liquid prepolymer . [1] Curing is induced by heat or suitable radiation and may be promoted by high pressure or mixing with a catalyst .
For heat exposure, the amino acid and urea samples started degradation at 100 °C (373 K; 212 °F) and for lactic acid, the decomposition process started around 50 °C (323 K; 122 °F). [4] These components are necessary for further testing, so in the forensics discipline, decomposition of fingerprints is significant.
Polymer stabilizers (British English: polymer stabilisers) are chemical additives which may be added to polymeric materials to inhibit or retard their degradation. Mainly they protect plastic and rubber products against heat, oxidation, and UV light.
Depolymerization is a very common process. Digestion of food involves depolymerization of macromolecules, such as proteins.It is relevant to polymer recycling.Sometimes the depolymerization is well behaved, and clean monomers can be reclaimed and reused for making new plastic.
To determine whether a polymer will undergo surface or bulk erosion, the degradation rate of the polymer in water (how fast the polymer reacts to water) and the rate of diffusion of water penetrating through the material must be considered. If the degradation process is faster than the diffusion process, surface erosion will occur since the ...