Characterization of degradation behavior of poly(glycerol maleate) films in various aqueous environments

Plastic pollution has become a serious environmental challenge, especially in the past two decades due to the ubiquitous use of plastics all over the world. To reduce plastic pollution, biodegradable polymers are in high demand as alternatives for common plastics. In this work, we study the degradability of poly(glycerol maleate)(PGM) in various aqueous environments to evaluate the influence of salinity and microorganisms on the degradation. PGM films are immersed in reverse osmosis (R.O.) water, fresh water, tap water, artificial seawater and seawater at 25 °C for 56 days. The mechanism of the degradation is discussed through mass remaining (%), water uptake (%), differential scanning calorimetry (DSC) and surface morphology via scanning electron microscope (SEM). It is revealed that PGM degrades efficiently in seawater and freshwater environments. Furthermore, with the presence of microorganisms, the degradation of PGM in seawater is slightly retarded, with over 95% of PGM films degraded within 56 days. Overall, PGM shows great potential as a biodegradable polymer that degrades rapidly in aqueous environments, regardless of the presences of microorganisms.