The physical and chemical properties of nylon

The physical properties of nylon

(1) Nylon has good elasticity. This is mainly because its molecular structure has a large amount of —CH2—, which is easy to bend, and the molecules in its amorphous region tend to be entangled randomly, so it has excellent stretch and resilience, good flexibility and high elasticity.

(2) Nylon has excellent dry strength and high wet strength.

(3) Nylon has a certain degree of moisture absorption, which is about 10 times that of polyester.

(4) Nylon fabric has excellent wear resistance, about 10 times higher than cotton fiber.

(5) Nylon fabric has good heat resistance, because it is a thermoplastic fiber, it will soften when heated to a certain temperature, and will melt when the temperature is increased. Therefore, special attention should be paid to printing and dyeing.

(6) Nylon also has natural anti-moth and anti-mildew properties, and is suitable as a material for decorative cloth.

The chemical properties of nylon

(1) Nylon has better stability to alkalis. When treated with 50% NaOH solution at room temperature, its strength is almost unchanged, but when the temperature rises above 60℃, the fiber is damaged.

(2) Nylon is sensitive to the action of acid, especially inorganic acid and strong organic acid. Both concentrated hydrochloric acid and concentrated sulfuric acid can decompose or completely dissolve nylon.

(3) Strong oxidants also have a destructive effect on nylon. Hydrogen peroxide, potassium permanganate, and sodium hypochlorite can break and degrade the molecular chain. But it has good resistance to sodium chlorite.

(4) It is insoluble in gasoline, benzene, ketones and other solvents, but it is soluble in phenols.

Due to the physical state of nylon itself such as crystallization, rotation, twist, fiber type, shape setting, the difference in tension before printing, temperature and pH changes, etc., it often leads to poor levelness of printing and dyeing. On the other hand, its glass transition temperature is lower than that of polyester, and it is also greatly affected by moisture, so special attention should be paid when printing and dyeing.