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By comparison the dependence of degradation rate on UV exposure and the availability of oxygen is broadly linear. As the oceans are cooler than land plastic pollution in the marine environment degrades more slowly. [40] [41] Materials buried in landfill do not degrade by photo-oxidation at all, though they may gradually decay by other processes.
Photo-aging is another degradation route for polycarbonates. Polycarbonate molecules (such as the aromatic ring) absorb UV radiation. This absorbed energy causes cleavage of covalent bonds which initiates the photo-aging process. The reaction can be propagated via side chain oxidation, ring oxidation or photo-Fries rearrangement.
Accelerated aging is testing that uses aggravated conditions of heat, humidity, oxygen, sunlight, vibration, etc. to speed up the normal aging processes of items. It is used to help determine the long-term effects of expected levels of stress within a shorter time, usually in a laboratory by controlled standard test methods.
The prediction of the ageing of plastic materials is a subject that concerns both users and manufacturers. It covers plastic materials (polymers, fillers and various additives) or intermediates that are the transformers that use their thermoplastic property for the manufacture of objects by processes such as extrusion, injection molding, etc.
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]
This is naturally present in the air at very low concentrations but is exceedingly reactive, particularly towards unsaturated polymers such as rubber, where it causes ozone cracking. The mechanism of ozonolysis is different from other forms of oxidation and hence requires its own class of antioxidant stabilizers.
A photopolymer or light-activated resin is a polymer that changes its properties when exposed to light, often in the ultraviolet or visible region of the electromagnetic spectrum. [1] These changes are often manifested structurally, for example hardening of the material occurs as a result of cross-linking when exposed to light.
Plastic pollution has also greatly negatively affected our environment. "The pollution is significant and widespread, with plastic debris found on even the most remote coastal areas and in every marine habitat". [77] This information tells us about how much of a consequential change plastic pollution has made on the ocean and even the coasts.