Biodegradable water-soluble polymers definitions

There have been numerous definitions proposed for environmentally degradable and biodegradable water-soluble polymers and plastics, almost every article written on the subject includes the author s favorite definitions. All tend to encompass the same broad concepts but are slightly different in phraseology depending on the author s perspective... 

To use organic molecules as a food source, microorganisms have to be able to take up the substance and metabolize it within their cells. A prerequisite is that the molecules are water-soluble and that they are small enough to pass through the cell walls and membranes of the microorganism. Polymers are typically not water-soluble and, by definition, are not small molecules [4]. Therefore, the biodegradation of polymers typically needs to follow four distinct steps. 

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