Popular science | Basic knowledge of nylon

Nylon is also polyamide fiber. It has a more well-known name, Nylon (Nylon). The English name is Polyamide (PA for short)

Nylon was invented on February 28, 1935. The inventor was Wallace Carothers of DuPont Company in Wilmington, USA.

Nylon was officially launched in 1938. The earliest Nylon product was a toothbrush brush made of Nylon, which was launched in February 1938. Sales began on May 24; nylon stockings worn by women were launched on May 15, 1940. Nylon fiber is the raw material for many man-made fibers, and hard Nylon is also used in the construction industry.

The general name of thermoplastic resins containing repeating amide groups – [NHCO] – on its molecular main chain, including aliphatic PA, aliphatic – aromatic PA and aromatic PA. Among them, aliphatic PA has many varieties, large output, and wide application. Its name is determined by the specific number of carbon atoms of the synthetic monomer.

The biggest advantages of nylon are its strong wear resistance, low density, light fabric, good elasticity, resistance to fatigue damage, good chemical stability, alkali resistance but not acid resistance!

The biggest disadvantage is that it has poor sunlight resistance. The fabric will turn yellow after being exposed to the sun for a long time, its strength will decrease, and its moisture absorption is not good, but it is better than acrylic and polyester.

1. Nylon 46 (PA46)

English name: Polyamide46 or Nylon46; referred to as PA46. Nylon 46, also known as polyamide 46, is polybutylene adipamide.

Its outstanding features are high crystallinity, high temperature resistance, high rigidity and high strength. Mainly used in automobile engines and peripheral components, such as cylinder heads, cylinder bases, oil seal covers, and transmissions. In the electrical industry, it is used in fields such as contactors, sockets, coil bobbins, and switches that require high heat resistance and fatigue resistance.

2. Nylon 4T (PA4T)

English name: Polyamide4T or Nylon4T; PA4T for short. Nylon 4T and PA4T are the first high-temperature nylons synthesized since the 21st century. It was born on September 27, 2007, 10 years ago. Among the polymer groups, it is the first high-temperature nylon invented after 2000.

The melting point of PA4T pure resin is very high, exceeding its decomposition temperature. If it is not copolymerized and modified to lower its melting point, it cannot be commercially used and its promotion will be extremely difficult. Therefore, the promotion of PA4T in the market generally requires copolymerization and modification. The common method is to copolymerize with PA66 and/or PA6 to lower the melting point. After modification, it has excellent comprehensive mechanical properties, good fluidity, excellent electrical properties, outstanding chemical corrosion resistance and high temperature resistance, and can meet the requirements of electronic and electrical, mobile terminal and other fields.

3. Nylon 56 (PA56)

English name ：Polyamide56 or Nylon56; Abbreviation: PA56. Nylon 56 is formed by the condensation polymerization of pentanediamine and adipic acid. Pentamethylenediamine can be extracted from natural organisms.

Environmental protection, good performance, and can improve the comfort of terminal fabrics. Its water absorption, glass transition temperature, strength, softness, hygroscopicity and resilience are better than some products of nylon 6, nylon 66 and polyester.

4. Nylon 6 (PA6)

English name: Polyamide6 or Nylon6, PA6 for short; Nylon 6, also known as polyamide 6, is polycaprolactam, which is obtained by the ring-opening polycondensation of caprolactam. Molecular structural formula:

Translucent or opaque Milky white resin has excellent mechanical properties, stiffness, toughness, wear resistance and mechanical shock absorption, good insulation and chemical resistance. It is widely used in many fields such as automobile parts and electronic and electrical components.

5. Nylon 66 (PA66)

English name: Polyamide66 or Nylon6; PA66 for short; Nylon 66, also known as polyamide 66, is polyhexamethylene adipamide. Compared with nylon 6, its mechanical strength, stiffness, heat resistance and wear resistance, and creep resistance are better, but its impact strength and mechanical properties are better.The vibration performance is degraded. It is widely used in automobiles, drones, electronics and electrical, etc.

6. Transparent nylon (semi-aromatic nylon)

English name: polytrimethyl hexamethylene

terephthalamide; transparent polyamide resin;

Transparent nylon is an amorphous polyamide, and its chemical name is: polytrimethylhexamethylene terephthalamide. The transmittance of visible light reaches 85% to 90%. It adds components with copolymerization and steric hindrance into the nylon component to inhibit the crystallization of nylon, thereby producing an amorphous and difficult-to-crystallize structure. It maintains the original strength and toughness of nylon and obtains transparent thick-walled products. The mechanical properties, electrical properties, mechanical strength and rigidity of transparent nylon are almost at the same level as PC and polysulfone.

7. Nylon 6T (PA6T)

English name: Polyamide6T or Nylon6T; PA6T for short. Nylon 6T, also known as polyamide 6T, is polyhexamethylene terephthalamide.

Its outstanding features are high temperature resistance (melting point is 370°C, glass transition temperature is 180°C, and can be used for a long time at 200°C), high strength, dimensional stability, and good welding resistance, making PA6T particularly suitable for adhesive technology (SMT) Use electronic connectors. Mainly used in automotive parts, oil pump covers, air filters, heat-resistant electrical components such as wire harness wiring boards, fuses, etc.

8. Nylon MXD6

Nylon-mxd6 is manufactured by Mitsubishi Generic name for a broad range of polyamides produced by Gas Chemicals from m-xylenediamine (mxda). It is a crystalline polyamide produced by the condensation of m-xylenediamine (mxda) with adipic acid, unlike nylon 6 and nylon 66. Nylon mxd6 is an aliphatic polyamide containing an aromatic ring in its main chain

Compared with nylon 6 and nylon 66, nylon MXD6 has the following good characteristics:

1. Greater strength and elastic modulus;

2. High glass transition temperature;

3. Low water absorption and moisture permeability;

4. Good crystallization speed and easy molding and manufacturing;

5. Good gas barrier properties.

These characteristics have led to many different applications for Nylon-MXD6 as packaging and molding materials, as well as in the production of monofilament.

9. Nylon 610 (PA610)

English name: Poly[imino-1, 6-hexanediylimino(1,10-dioxo-1,10-decanediyl)]; Polyamide 610; Nylon 610; referred to as PA610. Nylon 610, also known as polyamide 610, is polyhexanediamide

Translucent milky white color. Its strength is between nylon 6 and nylon 66. Small specific gravity, low crystallinity, low water absorption, good dimensional stability, good wear resistance, and self-extinguishing. Used in precision plastic parts, oil pipes, containers, ropes, conveyor belts, bearings, textile machinery parts, insulating materials and instrument cases in electrical and electronics, etc.

Nylon 612 (PA612)

English name: Polyhexamethylene dodecanamide; Polyamide 612; Nylon 612; PA612 for short. Nylon 612, also known as polyamide 612, is polyhexamethylene dodecanoyl diamide.

Nylon 612 is a kind of nylon with good toughness, smaller density than 610, extremely low water absorption, excellent wear resistance, small molding shrinkage, excellent hydrolysis resistance and dimensional stability. The main use is to make monofilament and cable coating for high-end toothbrushes.

Nylon 9T (PA9T)

English name: Polyamide9T or Nylon9T; PA9T for short. Nylon-9T, also known as polyamide-9T, is polynonanediamine terephthalamide.

The outstanding features are: It has low water absorption, with a water absorption rate of 0.17%; good heat resistance (melting point is 308°C, glass transition temperature is 126°C), and its welding temperature is as high as 290°C. Mainly used in electronics, electrical appliances, information equipment and automotive parts.

Nylon 10T (PA10T)

English name: Polyamide10T or Nylon10T; PA10T for short. Nylon 10T, polyamide 10T, polydecanediamine terephthalamide.

Its main features are very low hygroscopicity, high temperature resistance, excellent toughness, rigidity and dimensional stability, good fluidity and processing performance, easy coloring, high strength of welding fusion line, melting point as high as 300~316℃, and density of 1.42g/cm3. PA10T has a benzene ring and a long diamine flexible chain, which makes the macromolecules have a certain degree of flexibility, resulting in a high crystallization rate and crystallinity, and is suitable for rapid prototyping. Widely used in LED reflective brackets, motor end covers, brush brackets, gears, etc.

Nylon 1010 (PA1010)

English name: Polyamide1010; Nylon1010; PA1010 for short. Nylon 1010, also known as polyamide 1010, is polysebamide. Molecular structural formula:

Nylon 1010 is made from castor oil as the basic raw material. It was first successfully developed and industrialized by Shanghai Celluloid Factory in my country. Its biggest featureThe point is that it is highly ductile and can be stretched to 3 to 4 times the original length. It has high tensile strength, excellent impact and low temperature resistance, is not brittle at -60°C, and has excellent wear resistance and ultra-high temperature resistance. With excellent toughness and good oil resistance, it is widely used in aerospace, cables, optical cables, metal or cable surface coatings, etc.

Nylon 11 (PA11)

English name: Polyamide11 or Nylon11; PA11 for short. Nylon 11, also known as polyamide 11, is polyundecylactam.

Appears as a white translucent body. Its outstanding features are low melting temperature and wide processing temperature, low water absorption, good low-temperature performance, and good flexibility that can be maintained at -40°C to 120°C. Mainly used in automobile oil pipelines, brake system hoses, fiber optic cable coatings, packaging films, daily necessities, etc.

Nylon 12 (PA12)

English name: Polyamide12 or Nylon12; PA12 for short. Nylon 12, also known as polyamide 12, is polylaurylamide.

It is similar to nylon 11, but its density, melting point and water absorption are lower than nylon-11. It has the properties of a combination of polyamide and polyolefin due to its relatively large amount of toughening agent. Its outstanding features are high decomposition temperature, low water absorption and excellent low temperature resistance. Mainly used in automobile oil pipelines, instrument panels, accelerator pedals, brake hoses, muffler parts of electronic appliances, and cable sheaths.

Nylon 1212 (PA1212)

English name: Polyamide1212; Nylon1212; PA1212 for short. It is derived from the condensation polymerization of dodecanediamine and dodecanedioic acid. PA1212 has the lowest water absorption rate among nylons, good dimensional stability, oil resistance, alkali resistance, good abrasion resistance, chemical resistance, good transparency, and excellent toughness at low temperatures. Widely used in aerospace, automobiles, textiles, instruments, medical equipment, etc.

<span style="margin: 0px; padding: 0px; outline: 0px; max-width: 100%; letter-spacing: 2px; font-size: 16px; font