The surface of poly(ethylene naphthalate) film applicable to high temerature insulator for convection microwave oven was modified with silicone coating solutions in the presence of silane crosslinking agent. The structure and properties of the PEN films were investigated by using Fourier transform IR spectroscopy, viscometry, microscopy, and tensile tests. The experimental results showed that the coating with silicone enhanced thermal stability up to 200℃, and slightly lowered the tensile strength and elongation of the PEN films. Judging from dimensional stability results the silicone coated PEN films can not be used for higher temperature insulator above 230℃. Serious dimensional contraction of films was obtained during heat treatment at 250℃ even for 1h. However, the surface of those films still have same chemical structure of silicones. Therefore, If we use PEN film prestretched at 230℃ as base one it will be possible to prepare a high temperature insulator up to 230℃. Conclusively, a silicone coated PEN film can be suitable for the application to convection microwave oven door insulator at high temperature up to 230℃.

This research evaluated the environmental impact of waste film used in the farming industry which is subject to voluntary agreement by Waste Charge System using Life Cycle Assessment (LCA). When analyzing the environmental scores applying weighted values, production of raw materials, production of goods and disposal had nearly 73%, 15% and 11% of contribution to the environmental impact and also, amongst impact categories, resource depletion and global warming had 63% and 32% of contribution respectively. For resource depletion which had the highest contribution, production of raw materials, production of goods and disposal occupied around 86%, 9% and 4% of it, and the impact category of resource depletion that belongs to production of raw materials, accounted for about 54% of the whole environmental score. Here, over 95% of it was caused by crude oil. When investigating the contribution of each phase to global warming that is the key issue of low carbon green growth, production of raw materials, production of goods and disposal had respectively, 45%, 28% and 27% of contribution. As the result, production of goods and disposal had higher contributions than resource depletion. The entire contribution of production of goods and disposal to global warming was about 17%, and it is predicted that it would bring a huge impact, considering the possibility of establishing improvement plans. In the production of goods, electricity consumed was the main cause of global warming, and electricity used in the recycling process and incineration occupied approximately 52% and 42% of the disposal stage. In conclusion, we should pay attention to energy used in the production of goods and recycling for improving an environmental competitiveness of goods, and reduction of energy would be able to satisfy economic feasibility and environmental efficiency of the whole process of agricultural PE film.