How do nylon monofilament fishing nets withstand long-term corrosion in both saltwater and freshwater environments?
Publish Time: 2025-09-18
In modern fisheries and aquaculture, fishing nets, as core production tools, are constantly immersed in complex aquatic environments, facing severe challenges from chemical corrosion, biofouling, and physical wear. In saltwater (seawater), high salinity, strong electrolytes, and abundant microorganisms can accelerate the aging and corrosion of traditional materials. Nylon monofilament fishing nets, due to their excellent chemical stability and material properties, are one of the few ideal fishing nets suitable for long-term, stable use in both saltwater and freshwater environments. They offer not only high strength and wear resistance, but also excellent corrosion resistance, significantly extending their service life, reducing replacement frequency and reducing aquaculture and fishing costs.
1. The chemical stability of nylon materials is the foundation of corrosion resistance
Nylon (polyamide, PA) is a synthetic polymer, with nylon 6 or nylon 66 being the most commonly used materials in fishing nets. This type of material has a highly stable chemical structure, with a backbone composed of hydrocarbon chains connected by amide bonds. Its overall polarity is moderate, making it extremely resistant to common environmental media such as water, salt, and weak acids and bases. In freshwater environments, nylon monofilaments undergo virtually no chemical reaction with water, have low water absorption, and do not hydrolyze or swell even after prolonged immersion. In saltwater, high concentrations of electrolytes such as sodium chloride and magnesium ions are highly corrosive to most metals and natural fibers. However, the dense molecular chain structure of nylon is not easily penetrated or destroyed by ions, making it highly resistant to chemical attack from seawater and preventing strength loss due to material degradation.
2. Excellent Salt Spray and Chloride Ion Resistance
Chloride ions in seawater are a major cause of material corrosion, particularly penetrating metal mesh and some synthetic fibers. Due to its non-electrolyte properties, nylon monofilaments do not participate in electrochemical reactions and do not experience the "galvanic corrosion" or "pitting" that occurs with metals. Furthermore, modern nylon is often added with salt spray stabilizers and antioxidants during production to further enhance its durability in high-salt environments. Experiments have shown that high-quality nylon monofilament retains over 85% of its breaking strength after 12 months of continuous seawater immersion, significantly exceeding that of other common fishing net materials.
3. UV-resistant and anti-aging treatments extend outdoor life
Although nylon itself possesses a certain degree of weather resistance, prolonged exposure to sunlight can still cause molecular chain breakage, leading to brittleness and reduced strength. Therefore, highly effective UV absorbers are added to nylon monofilament used in fishing nets during the spinning process, creating a "built-in protective layer." In particular, the carbon black component of black or dark-colored nylon monofilament not only absorbs UV rays but also evenly disperses light energy, significantly slowing the photooxidation process. This UV-resistant treatment ensures long-term use of nylon monofilament fishing nets, even in tropical waters with strong sunlight, preventing brittleness and breakage due to aging.
4. Smooth and dense surface inhibits biofouling and corrosion.
The surface of nylon monofilament is precision-brushed to a smooth, even finish, making it impervious to the adhesion of algae, shellfish, bacteria, and other marine organisms. Biofouling not only burdens weight but also creates localized microclimates, accelerating material corrosion. The low surface energy and dense structure of nylon monofilament effectively reduce the initial points of biofouling. Combined with an antifouling coating or copper ion composite technology, the net's biofouling resistance is further enhanced. Even in eutrophic freshwater aquaculture areas, nylon nets are resistant to moss and mildew, maintaining cleanliness and permeability.
5. Stable physical properties adapt to changing hydrological environments.
Nylon monofilament exhibits excellent flexibility and elastic recovery, withstanding repeated stretching during tidal fluctuations, current impacts, and trawling operations without fatigue fracture. Its low water absorption ensures dimensional stability in alternating wet and dry environments, preventing expansion due to water absorption or shrinkage due to drying that could affect the mesh structure. This maintains fishing efficiency and structural integrity over long-term use.
The nylon monofilament fishing net's corrosion-resistant performance in both saltwater and freshwater environments is due to its inherent chemical inertness, excellent salt and water resistance, advanced UV treatment, and smooth, anti-fouling surface. It not only resists chemical attack in water but also effectively addresses the challenges of biofouling and physical wear.
