코로나방전을 이용한 Polypropylene과 Polyethylene의 표면처리에 관한 연구

Abstract

The characteristics changes of polypropylene film surface treatment was studied by changing the moving speed and power supply by using corona discharge. The results of the surface treatment of the corona discharge were as follows. (1) The change of the contact angle according to the moving speed of the film during corona discharge surface treatment was experimented. When the moving speed of the film was decreased from 1.666 m/sec to 0.083 m/sec, the contact angle was decreased from 80 ° to 64 °, and the wettability was greatly improved. (2) As the supply power increased from 0.4 kVA to 2 kVA during the corona discharge surface treatment, the contact angle was reduced from 77 ° to 65 ° and the wettability was greatly improved. Corona discharge surface treatment efficiency decreases as the moving speed decreases and as the supply power increases. It can be considered that the surface tension is increased and the wettability is improved and the adhesion between the film and the coating is enhanced. (3) The surface of the corona discharge treated polypropylene film was confirmed by scanning electron microscope(SEM). As the moving speed of the film is lowered in the physical phenomenon observation and the supply power is increased, the surface of the polypropylene film is formed with a lot of irregularities by the corona discharge so the phenomenon of improving the adhesion, surface energy and wettability was confirmed by photographs. (4) The tensile strength of polypropylene films remained almost unchanged due to the corona discharge surface treatment, and it was judged that corona discharge treatment had little effect on the internal properties of the polyethylene. The surface treatment of the film with the corona discharge was applied to improve the adhesion of the low density and high density polyethylene film and the results were as follows. The change of contact angle according to feeding speed of polyethylene film during corona discharge surface treatment was investigated. (5) When the feeding rate of the film was decreased from 1.666 m/sec to 0.083 m/sec, the contact angle of the low density polyethylene decreased from 80 ° to 64 ° , and the contact angle of the high density polyethylene decreased from 73 ° to 60 °. High-density polyethylene has improved wettability than low-density polyethylene. (6) The contact angle of low density polyethylene decreased from 75 ° to 58 ° and the contact angle of high density polyethylene decreased from 75 ° to 65 °, when the power supply was increased from 0.4 kVA to 2 kVA during corona discharge surface treatment. The low-density polyethylene has a much higher wettability than the high-density polyethylene. However, when the power supply increased to 2 ㎸A or more, it decreased. Therefore, the corona discharge surface modification efficiency was lowered as much as possible, so that the corona discharge treatment time was lengthened, and the power supply was increased to improve the surface treatment effect. (7) The surface of the low density and high density polyethylene film subjected to the corona discharge treatment was confirmed by a scanning electron microscope. As the moving speed of the film deteriorated and the supply power increased, the anchor effect and the etching effect of the surface due to the corona discharge caused the improvement of the wettability of the surface so it became hydrophillic, and it can be confirmed by photographs. (8) The tensile strength of low - density and high - density polyethylene films remained almost unchanged due to the corona discharge surface treatment, and it was judged that corona discharge treatment had little effect on the internal properties of the polyethylene.