Determination of Mesh Breaking Strength of Polyamide Fishing Nets

Pollutants and other external factors effect the strength and  service life of fishing nets. The effects of some pollutants such as heavy metals and temperature on the mesh breaking strength of knotless polyamide (PA) fishing nets were determined in this study. The PA net samples were subjected to heavy metal solutions containing Cd (Cadmium), Cu (Copper), Ni (Nickel), Hg (Mercury), Zn (Zinc), Cr (Chromium) and Pb (Lead) for 14 days at 99°C in metal and glass containers. Also, the samples were hold on metal and glass surfaces and suspended in the air at 130 and 175°C for the periods of 30 min., 1 and 2 hours. The order of breaking strenght values of heavy metal treated samples in metal containers was found Ni> Cd >Pb > Zn> Hg> Cu> Cr, respectively, whereas the order of samples was Cr> Hg> Cu> Pb> Zn> Cd> Ni for glass containers. Regarding to the test conditions and the temperature, the breaking strenght values of samples treated with 130°C were found significantly high (p˂0.05) compared with those hold at 175°C for both metal and glass surfaces and air suspended groups in all durations.