The meaning of “biodegrade” is very clear: complete chemical dissolution by bacteria or other biological means. The term is often confused with “degrade,” which simply means wearing down or the breakdown of material. Materials that biodegrade go away – materials that degrade simply break down in some fashion but do not go away. Oxo-degradable plastics are an example of a material that degrades, but does not biodegrade.
Some bioplastics will biodegrade naturally, such as PHA (polyhydroxyalkanoate). PHA is twice as expensive as most polymers, so not the material of choice in most packaging applications. Recent advances in formulating additives to promote biodegradation have been successful, such as EcoPure, but the public remains confused as to which additives biodegrade and which just degrade the package and fall apart.
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