• Title/Summary/Keyword: Gear Mechanism

검색결과 171건 처리시간 0.021초

Resistance to Weathering with Materials for fisheries Facilities 1. Photodegradation Mechanisms of Netting Twines for Fisheries Facilities (수산시설용 재료의 내후성에 관한 연구 1.그물실의 자외선 열화기구)

  • 김태호
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • 제36권1호
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    • pp.45-53
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    • 2000
  • To analyze the photodegradation mechanism of materials for fisheries facilities which stand for considerable time immediately under or even partly above the water surface, such as cage collar, cage net, stationary fishing gear, egc. after 900 hours exposure, weathering experiments on 3 kinds of netting twines like dyed polyethylene(PE) and nylon, and non-treated high strength PE(Hi-PE) were carried out by using xenon light source. The results obtained are as follows : It was observed by scanning electron micrograph(SEM) that a good protection by pigments was obtained in PE and nylon specimen, while crack was rapidly progressed at the surface of Hi-PE one owing to etching by UVR. There was a little increase in density resulting from reorientation of polymer chain, chain scission, etc. in Hi-PE specimen. A wide angle X-ray diffraction showed that 3 kinds of specimens had no fundamental changes in polymer crystalline structure considering each 2$\theta$ of diffraction peak. Remaining tenacity of netting twines was in order of PE, nylon, and Hi-PE after having been exposed to the effect of 900 hours. PE and nylon treated with stuffs were shown to be more resilient than non-treated Hi-PE as confirmed by SEM.

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