The performance of the fishing net monofilament nylon varies with the amount of water absorption. Due to the type, structure and process of the nets, the changes in their properties are different. The performance changes after water absorption are mainly shown in the following aspect:

1. Changes in quality after the network cable is immersed in water, the water is first immersed in the air between the fibers, and then penetrated into the fibers. The water absorption of cotton thread and Manila hemp thread is rather rapid one day after soaking, and the water absorption is large, and then gradually slow. Among the synthetic fiber materials, the largest suction basin is vinylon cable. Some tests have shown that after immersing the network cable for 11 hours, take it out without dripping and call it a quality basin. The water absorption rate of vinylon network cable is 80%, nylon is 36%, polyvinyl chloride is 32%, and polyvinylidene chloride is 11%.

2. Changes in fishing net nylon hardness: The diameter of the wire swells after absorbing water, which corresponds to an increase in twist, which causes an increase in hardness, which is unfavorable for some fishing gear (such as gillnets). Synthetic fiber mesh with low moisture absorption is relatively soft after entering water, especially PA filament. The mesh becomes very soft in wet state, which is of great significance to the use of ropes.

3. The length of the net fishing nylon wire changes in the water after absorbing water, which will cause the change of the mesh size and the deformation of the fishing gear. Therefore, when designing and assembling fishing gear, the shrinkage or elongation of the material must be considered.

The antifouling agent for fishing nets must meet the following conditions:

The toxic substance infiltrates very little, but the female killing effect on fouling organisms is very extensive;

There is a moderate amount of seawater solubility:

There is no severe pollution and pollution to the sea, and no obvious toxicity and irritation to humans and fish;

The raw materials are easily available and the cost is not high:

Long-lasting, long-term antifouling activity can be maintained on the surface of the coating film.