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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 ...
The RTI is part of the longterm thermal aging program (LTTA) described in the UL 746B standard from UL. [1] During the process of the UL 746B program, the degradation in hot air of certain properties of the material like dielectric and mechanic strength, is investigated with regards to thermal-aging. For a full study, the candidate material (B ...
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]
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 ...
Processes in the thermal degradation of organic matter at atmospheric pressure.. Thermal decomposition, or thermolysis, is a chemical decomposition of a substance caused by heat. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes.
Thermal depolymerization, which breaks down plastics and other polymers into monomers and oligomers. Ceramization [12] involving the formation of polymer derived ceramics from preceramic polymers under an inert atmosphere. Catagenesis, the natural conversion of buried organic matter to fossil fuels. Flash vacuum pyrolysis, used in organic ...
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.
A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling. [ 1 ] [ 2 ] Most thermoplastics have a high molecular weight .