Biodegradability of nylon 4 film in a marine environment

Biodegradability of nylon 4 in seawater from Tokyo Bay was investigated by weight loss and biochemical oxygen demand (BOD) of nylon 4 films. The remaining weight of nylon 4 film decreased with incubation time in the seawater, and the percentage of weight loss of nylon 4 film was 30% after 3 weeks. BOD biodegradability of nylon 4 film was approximately 80% within 25 days. Scanning electron microscopy images of the nylon 4 film before and after the seawater treatment revealed that the surface of the nylon 4 films was eroded after biodegradation in seawater. The average molecular weights of the nylon 4 films indicated no significant difference between before and after 30% weight loss of the film. Based on the present data, nylon 4 film was degraded on the surface of the film in the seawater. Furthermore, microbial degradation seemed to be one of the main degradation mechanisms of nylon 4.