There are many varieties of nylon yarn, the most important of which are nylon 6 yarn and nylon 66 yarn. The outstanding feature of nylon yarn is its excellent wear resistance, ranking first among all fibers, 10 times that of cotton yarn.
Nylon 6 Yarn and Nylon 66 Yarn
Table of Contents
There are many varieties of nylon yarn, the most important of which are nylon 6 yarn and nylon 66 yarn. The outstanding feature of nylon yarn is its excellent wear resistance, ranking first among all fibers, 10 times that of cotton yarn. The elasticity of nylon yarn is also very good, and it has good moth resistance and corrosion resistance. Nylon fabrics are light-weight fabrics, and are only listed after polypropylene and acrylic fabrics in synthetic fabrics.
Main advantage: Higher abrasion resistance than all other fibers. The best wear resistance. High elastic recovery rate.
Disadvantages: poor heat resistance and light resistance. The hold is also poor, not as stiff as polyester. Hygroscopicity and dyeability are poor.
Application Of Nylon Yarn
In the textile field, nylon is mainly filament yarn, and a small amount of short fiber is mainly used for blending with wool, cotton or other chemical fibers, in order to improve the strength and wear resistance of the fabric. Part of nylon filament yarn is used for silk, gauze, lace, etc., and most of it is processed into elastic yarn, which is used to make socks, nylon shirts, gloves, etc. that are durable. Industrial nylon yarn accounts for more than 40%. Because nylon yarn has high strength, fatigue resistance, strong impact resistance and good affinity with rubber, it is suitable for making tire cords such as trucks and airplanes. Cotton fishing nets are 4 to 5 times longer. In addition, it is also used for cables, parachutes, soft ladders, conveyor belts and nylon ropes.
climbing ropd made of nylon yarn
Development History Of Nylon 6 Yarn And Nylon 66 Yarn
In 1935, DuPont Carothers of the United States successfully researched the polycondensation of adipic acid and hexamethylene diamine into "nylon 66" polymer. From 1936 to 1937, the technology of making nylon 66 yarn by melt spinning was discovered. It was industrialized by the American DuPont Company at the end of 1939.
In 1938, the German IG company Schlak successfully used a single caprolactam as a raw material, and aminocaproic acid as an initiator to heat and polymerize to make polycaprolactam. In 1939, the experimental production of nylon 6 yarn was carried out. In 1943, it was industrially produced by the German company Farben.
Masterbatch - the raw material of nylon yarn
Physical Properties Of Nylon 66 And Nylon 6
Nylon 6 is polycaprolactam, while nylon 66 is polyhexamethylene diamine adipic acid. Nylon 66 is 12% harder than nylon 6, and theoretically, the higher the hardness of nylon, the more brittle the fiber is, and the easier it is to break. But in the use of carpets this small difference is indistinguishable.
Easy to fade under the action of ozone and nitrous oxide
easy to dye
Fiber elasticity is better
Soft to the touch
Common Characteristics Of Nylon 6 And Nylon 66
Nylon 6 yarn and Nylon 66 yarn have poor light fastness. Under prolonged sunlight and ultraviolet light, the strength decreases and the color turns yellow.
The heat resistance of nylon 6 yarn and nylon 66 yarn is not good enough. At 150 °C, it turns yellow after 5 hours, the strength and elongation decrease significantly, and the shrinkage rate increases.
Nylon 6 yarn and Nylon 66 yarn have good low temperature resistance, and their resilience does not change much when the temperature is below minus 70 °C.
Nylon 6 yarn and Nylon 66 yarn have strong resistance to microbial action, and their resistance to microbial action in muddy water or alkali is second only to vinyl chloride.
In terms of chemical properties, nylon 6 yarn and nylon 66 yarn have alkali resistance and reducing agent resistance, but have poor performance in acid resistance and oxidant resistance.
The Difference Between Nylon 66 Yarn And Nylon 6 Yarn
Nylon 66 yarn has better strength and abrasion resistance than nylon 6 yarn, and has a finer hand.
The price of nylon 66 yarn is more expensive than nylon 6 yarn, and it feels softer than nylon 6 yarn. It can be used as microfiber and high-end apparel fabric. Now, high-quality down fabrics on the market use nylon 66 yarn. It feels soft, light and soft to the touch. Anti-feather effect. However, dyeing is difficult, not easy to dye, requires high temperature dyeing, and the color fastness is not very good.
Both nylon 66 yarn and nylon 6 yarn are polyamide fibers. Nylon 66 yarn is produced by polycondensation of hexamethylene diamine adipate. Nylon 6 yarn is produced by polycondensation of caprolactam. From the point of view of molecular structure, these two fibers are very similar, so the physical and chemical properties of both are basically similar.
Nylon 6 yarn products have the characteristics of high strength, wear resistance, softness and mild skin touch, and have a wide range of uses in the fields of clothing, silk, umbrellas, fishnet yarns, cords, BCF carpet yarns and engineering plastics. The nylon 66 yarn is more used in the industrial field.
Nylon 66 yarn and Nylon 6 yarn are basically similar in performance and application, and can be used for pure spinning or blending to make various fabrics and knitwear. However, nylon 66 yarn has a higher melting point and better heat resistance, so it is more suitable for the manufacture of heat-resistant strain products, fabrics washed with heat-resistant water, and aircraft tire cords; nylon 66 yarn also has a high elastic modulus, which is also suitable for For multi-folded and woven fabrics. The characteristic of nylon 6 yarn is that it feels softer than nylon 66 yarn.
The main difference between nylon 66 yarn and nylon 6 yarn is shown in Table 1, and the difference in their performance is shown in Table 2.
Table 1 The main difference between nylon 66 yarn and nylon 6 yarn
Nylon 66 yarn
Nylon 6 yarn
Chemical Name
Polyhexamethylene adipate
Polycaprolactam
melting point
250-265 ℃, slightly yellow at 150 ℃
215-220 ℃
Softening Point
230℃
180℃
Acid resistance
Weak acid resistance, soluble and partially decomposed in concentrated hydrochloric acid, concentrated sulfuric acid, concentrated nitric acid
More than 16% concentrated hydrochloric acid, concentrated sulfuric acid, concentrated nitric acid can partially decompose and dissolve
Alkali resistance
Good alkali resistance at room temperature, but alkali will damage fibers when it is higher than 60 degrees
In 50% caustic soda solution, 28% ammonia solution, the strength hardly decreases
Solvent resistance
Insoluble in common solvents, but soluble in some acid compounds and 90% formic acid.
Insoluble in general solvents, but soluble in phenols (phenol, m-cresol, etc.), in concentrated hexanoic acid, swelling in glacial acetic acid, and heating can make it dissolve
Mechanical properties
Good rigidity and better elastic modulus
Good toughness, impact resistance and dissolution resistance are better than nylon 66 yarn
glass transition temperature
50℃
48℃
application
Tire cord and hot water laundering fabrics, and woven fabrics
Fishing nets, tents, industrial fabrics and other civil and industrial fields
Other properties
Difficult to dye, not easy to color; feel softer than nylon 6 yarn
Moisture absorption is stronger than nylon 66 yarn
price
The price of nylon 66 yarn is more expensive than nylon 6 yarn
Table 2 The difference between nylon 66 yarn and nylon 6 yarn in performance
Nylon 66 yarn
Nylon 6 yarn
melting point
higher melting point
lower melting point
crystal structure
The crystal structure is tight
The crystal structure is loose
Degree of influence by ozone and nitrous oxide
Less affected by ozone and nitrous oxide
Easy to fade under the action of ozone and nitrous oxide
