Biodegradable additives

Biodegradable additives are additives that enhance the biodegradation of polymers by allowing microorganisms to utilize the carbon within the polymer chain itself.

Biodegradable additives attract microorganisms to the polymer through quorum sensing after biofilm creation on the plastic product. Additives are generally in masterbatch formation that use carrier resins such as polyethylene, polypropylene, polystyrene or polyethylene terephthalate.

ASTM D5511-12 testing is for the "Anerobic Biodegradation of Plastic Materials in a High Solids Environment Under High-Solids Anaerobic-Digestion Conditions"

ASTM D5526-12 testing is for the "Standard Test Method for Determining Anaerobic Biodegradation of Plastic Materials Under Accelerated Landfill Conditions"

ASTM D5210-07 testing is for the "Standard Test Method for Determining the Anaerobic Biodegradation of Plastic Materials in the Presence of Municipal Sewage Sludge"

A simple chemical equation of the process is:

C₆H₁₂O₆ → 3CO₂ + 3CH₄

Interpretation of this process is as follows - In most cases, plastic is made up of hydrophobic polymers. Chains must be broken down into constituent parts for the energy potential to be used by microorganisms. These constituent parts, or monomers, are readily available to other bacteria. The process of breaking these chains and dissolving the smaller molecules into solution is called hydrolysis. Therefore, hydrolysis of these high-molecular-weight polymeric components is the necessary first step in anaerobic biodegradation. Through hydrolysis, the complex organic molecules are broken down into simple sugars, amino acids, and fatty acids.

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