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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 ]
Thermal degradation of polymers. 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 ...
Plastic pollution is the accumulation of plastic objects and particles (e.g. plastic bottles, bags and microbeads) in the Earth's environment that adversely affects humans, wildlife and their habitat. [1][2] Plastics that act as pollutants are categorized by size into micro-, meso-, or macro debris. [3] Plastics are inexpensive and durable ...
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be molded, extruded or pressed into solid objects of various shapes. This adaptability, plus a wide range of other properties, such as being lightweight, durable, flexible, and inexpensive ...
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] Photo-oxidation causes the polymer chains to break (chain scission), resulting in the material becoming ...
Polylactic acid, also known as poly (lactic acid) or polylactide (PLA), is a thermoplastic polyester (or polyhydroxyalkanoate) with backbone formula (C3H4O2)n or [–C (CH3)HC (=O)O–]n, formally obtained by condensation of lactic acid C (CH3) (OH)HCOOH with loss of water (hence its name).
Secondary microplastics are small pieces of plastic derived from the physical breakdown and mechanical degradation of larger plastic debris, both at sea and on land. [5] Over time, a culmination of physical, biological, and chemphotodegradation, including photo-oxidation caused by sunlight exposure, can reduce the structural integrity of ...
Relative thermal index. 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. [1]