Biodegradable polymer degradation rate

Degradation studies using biodegradable polyphosphazenes clearly demonstrate that the polymer degradation rate can be efficiently tuned by incorporating different hydrophilic, hydrophobic, or bulky substituent groups. This... 

These functional groups can be incorporated into the polymer backbone either as carbon monoxide or vinyl ketones, but as with the biodegradable polymers, the rate of degradation in the environment is slow. Furthermore, in covered landfill sites where the materials would be deprived of light, air and water, the rate of degradation would be very slow. 

It is often claimed that biodegradable polymers degrade through random scissions of the polymer chains. However the ester bonds next to chain ends may hydrolyse faster than those inside the chains, which is known as end scission. To account for the effect of end scission, GleadaU et al. (2014) used separate equations for random scission rate, / dt, and end scission rate, / dt, respectively, such that... 

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