Abstract:
Seines or fishing nets are commonly made from polypropylene (PP) and nylon 6. These polymers are non-degradable materials. Their wastes are the cause of sea pollution and create microplastic problems. This research aimed to study the applications of environmentally friendly materials to replace conventional polymers. The polymer blends of polyoxymethylene (POM) and poly(lactic acid) (PLA), a biodegradable polymer, exhibited excellent toughness properties and was suitable for fiber processing. The multifilament process of POM/PLA blends for the seine applications was studied.
It was found that the POM/PLA blends with weight ratios of 70/30 showed proper properties for the fiber applications, but a lubricant substance was needed for multifilament processing. Two lubricants, polyethylene glycol (PEG) and ethylene bis stearamide (EBS), were added to the POM/PLA blends with the content of 0.5, 1.0 and 1.5 phr processed through a single screw extruder at 180-210oC. The multifilament was first hot drawn at a spinning speed of 5 m/min and second hot drawn at a spinning speed of 20, 25, and 30 m/min. The fiber products were subject to thermal, physical and mechanical property analysis. The biodegradability of POM/PLA multifilament in seawater was evaluated and compared with imitated seawater (salt water) and distilled water.
The multifilament property analysis revealed that the lubricant decreased the melt flow index of polymer blends, but did not affect the crystalline melt temperature of the fibers. The lubricant content 1 and 1.5 phr assisted the drawing behavior of the fibers and leveled up the mechanical properties due to the better orientation of the polymer molecules. The biodegradability test in seawater was calculated from loss weight and morphology of the fibers. Biodegradability was found to be highest in seawater followed by the imitated seawater and the distilled water. It was found that the lubricant did not affect the biodegradability of the multifilament.