Polymer degradation aerobic

Arnosti, C., and Repeta, D.J. (1994) Oligosaccharide degradation by an aerobic marine bacteria characterization of an experimental system to study polymer degradation in sediments. Limnol. Oceanogr. 39, 1865-1877. 

Cellulosic materials such as wood flour, paper, and rayon improve biodegradation of poly(lactic acid) in aerobic soil (Figure 11.19). The polymer degrades at a rate similar to... 

Raghavan D, Wagner GC,Wool RP (1993) Aerobic biometer analysis of glucose and starch biodegradation. J Environ Polym Degrad 1 203-211... 

Nishida, H. Tokiwa, Y. Distribution of poly(P-hydroxy-butyrate) and poly(e-caprolactone) aerobic degrading microorganisms in different environments. J. Environ. Polym. Degrad. 1993,1 (3), 227-233. 

Dominant groups of microorganisms and the degradative pathways associated with polymer degradation are often determined by the environmental conditions. When O2 is available, aerobic microorganisms are mostly responsible for destruction of complex materials, with microbial biomass, CO2, and H2O as the final products. In contrast, under anoxic conditions, anaerobic consortia of microorganisms are responsible for polymer deterioration. The primary products will be microbial biomass, CO2, CH4 and H2O under methanogenic (anaerobic) conditions (Barlaz et al., 1989) (e.g., landfills/compost) (Fig. 8.5). 

Compared with investigations of polymer degradation under aerobic conditions, very little information is available in the literature regarding the degradation of... 

Massardier-Nageotte, V., Pestre, C., Cmard-Pradet, T., Bayard, R., 2006. Aerobic and anaerobic biodegradabdity of polymer films and physico-chemical characterization. Polym. Degrad. Stabd. 91, 620—627. 

Like each type of degradation, biodegradation also has several undesired effects. Uncontrolled microbial decomposition might occasionally cause pollution of the groundwater and of the surrounding air. In order to avoid pollution, biodegradable polymers and aerobic composting procedures have been developed. 

Regeneration of the reduced metal ion by redox reaction during catalysis is essential to continue PO degradation. Fe is the thermodynamically favored oxidation state for iron under aerobic and alkaline conditions, whereas Fe is favored under anaerobic and acidic conditions. Under most disposal and environmental conditions Mn " is favored. It is therefore unlikely that a particular metal catalyst will perform equally well in a wide range of disposal situations. Due to environmental pH values it is difficult for such catalysts to be recycled for further free radical generation. Both Fe and Fe " salts can precipitate as insoluble oxides or sulfides under environmental conditions, reducing the polymer degradation potential. 

A schematic of polymer degradation under aerobic and anaerobic conditions... 

Figure 6.7 Schematic of the degradation of polymers under aerobic and anaerobic conditions by MOs.

The migration of PAEs from the polymers leads emissions to the environment during their production, transport, storage, manufacture, use, and disposal [8, 15, 40, 69]. Once in the different environmental compartments phthalates are subject to photo degradation, biodegradation, aerobic and anaerobic degradation and, thus, generally do not persist in the outdoor environment [8, 70]. 

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