Poly (ethylene terephthalate) (PET) 필름은 여러 가지 우수한 필름 특성으로 인하여 다양한 방면에서 이용되 고 있다. 그러나 PET 필름은 낮은 표면에너지로 인하여 젖음성과 접착력이 약해 그 응용에 제약이 있다. 따라서 PET 필름이 유연 전자회로 기판으로 사용되기 위해서는 필름의 표면에너지를 필름 자체의 특성에 변화주지 않는 범위에서 변화시켜 낮춰줘야 할 필요가 있다. 본 연구에서는 상용의 PET 필름에 자외선과 공기-플라스마 처리를 행하였으며, 각각의 조건에 따른 필름의 표면을 접촉각 측정기, X-선 분광기 등을 사용하여 조사하였다. 또한 시간에 따른 표면특성의 변화를 연구하였다. 그 결과 자외선과 공기-플라스마로 처리된 필름은 표면이 극성으로 변화하였으며, 시간에 따라 서서히 원래의 극성으로 돌아가는 것을 확인하였으며, 초기 상태로의 극성의 회복 시간은 자외선과 공기-플라스마 처리 시간과 관련되는 것을 확인하였다. 이는 PET 필름이 인쇄전자 분야에서 유연기판 재료로서 이용되는 데에 중요한 결과라고 할 수 있다.

This study investigated the application of experimental design methodology to optimization of conditions of air-plasma and oxygen-plasma oxidation of N, N-Dimethyl-4-nitrosoaniline (RNO). The reactions of RNO degradation were described as a function of the parameters of voltage (X1), gas flow rate (X2) and initial RNO concentration (X3) and modeled by the use of the central composite design. In pre-test, RNO degradation of the oxygen-plasma was higher than that of the air-plasma though low voltage and gas flow rate. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the RNO removal efficiency and test variables in a coded unit: RNO removal efficiency (%) = 86.06 + 5.00X1 + 14.19X2 - 8.08X3 + 3.63X1X2 - 7.66X2 2 (air-plasma); RNO removal efficiency (%) = 88.06 + 4.18X1 + 2.25X2 - 4.91X3 + 2.35X1X3 + 2.66X1 2 + 1.72X3 2 (oxygen-plasma). In analysis of the main effect, air flow rate and initial RNO concentration were most important factor on RNO degradation in air-plasma and oxygen-plasma, respectively. Optimized conditions under specified range were obtained for the highest desirability at voltage 152.37 V, 135.49 V voltage and 5.79 L/min, 2.82 L/min gas flow rate and 25.65 mg/L, 34.94 mg/L initial RNO concentration for air-plasma and oxygen-plasma, respectively.

Plasma-photocatalytic oxidation process was applied in the decomposition of Triethylamine(TEA) and Methyl ethyl ketone(MEK). Plasma reactor was made entirely of pyrex glass and consists of 24 ㎜ inner diameter, 1,800 ㎜ length and discharge electrode of 0.4 ㎜ stainless steel. And initial concentrations of TEA and MEK for plasma-photocatalytic oxidation are 100 ppm. Odor gas samples were taken by gas-tight syringe from a glass sampling bulb which was located at reactor inlet and outlet, and TEA and MEK were determined by GC-FID. For plasma process, the decomposition efficiency of TEA and MEK were evaluated by varying different flowrates and decomposition efficiency of TEA and MEK increased considerably with decreasing treatment flowrates. For photocatalytic oxidation process, also the decomposition efficiency of TEA and MEK increased considerably with decreasing treatment flowrates. The decomposition efficiency of MEK was 57.8%, 34.2%, 18.8% respectively and the decomposition efficiency of TEA was reached all 100%. This result is higher than that of plasma process only. From this study, the results indicate that plasma-photocatalytic oxidation process is ideal for treatment of TEA and MEK.