부산대학교 도서관

In order to evaluate the biodegradability of the LDPE added with several degradation inducing agents, the LDPE film was buried in an composting chamber containing kitchen dust. After only several weeks of burial, a number of hyphae and spores observed on the surface of the film. This means the microbial activity is extremely high on the surface of the film. We detected calcium palmitate on the film surface. It is well known that the palmitic acid is an important constituent of kitchen dust. Thus we considered that the palmitic acid migrate from kitchen dust to film surface, and that this compound plays an important role in the acceleration of biodegradation of LDPE. The decrease of tensile strength of LDPE buried in kitchen dust was much faster than the one buried in coppice soil. The result seems to correspond the stronger FT-IR carbonyl band of the former. The decrease of tensile strength was evident even for the LDPE which does not contain any degradation inducing agents. Thus we concluded that the biodegradation of LDPE really proceeds in the compost composed from kitchen dust. It was suggested that the fatty acids included in vegetables migrate to film surface to promote the microbial activity, and to accelerate the biodegradation of LDPE chain. ESR spectra of the film showed that the radical concentration increased with the treating time with the compost.