Biodegradation and biodeterioration of polymeric materials affect a wide range of industries including manufacturing, aviation and space. Degradability of polymeric materials by microorganisms has been observed and the degree of degradability is determined mostly by the chemical structures of polymeric materials and the presence of degradative microbial population. Current understanding of polymer degradability has been advanced in recent years through the application of advanced detection techniques in both the biology of microorganisms and corrosion science, but the subject is still inadequately addressed. This is clearly shown by the limited amount of information available on biodeterioration of synthetic polymeric materials. In this review, polymers are treated according to their biodegradability, namely chemically modified natural polymers, synthetic polymers, recalcitrant polymers, and non-biodegradable polymers. One major advance in this area of research and development is the introduction of Electrochemical Impedance Spectroscopy (EIS) for sensitive detection of polymer degradation. Examples of the electronic insulation polyimides, fiber-reinforced polymeric composite and polymeric coatings by natural population of microorganisms have been established using this technique. Microorganisms and microbial biofilms are capable of degrading the material and fungi seem to be more effective than bacteria. During degradation, general EIS spectra indicative of microbial attack occur in several steps depending on the chemical composition of polymers. An initial decrease in impedance has been detected due to the transport of water and solutes into the polymeric matrices and a second decrease in impedance occurred as a result of polymer degradation. Microbial biofilms can form on surfaces of synthetic polymers and subsequent material degradation of materials due to the activities of microorganisms may be resulted. It is clear that candidate materials for use in different applications need to be carefully evaluated for usceptibility to microbial attack.
- Electrochemical impedance spectroscopy
- Electronic insulation polyimides
- Fiber reinforced polymeric composirte