The term “Nylon PA” describes a plastic made of polyamide resin. This kind of resin can be made either by the ring-opening polymerization of lactams that are created after the dehydration of amino acids or by condensation polymerization of diamines and dibasic acids. PA does not vary gradually as the heating temperature rises like PS, PE, PP, etc. The melting point is clearly between 215-225 °C, while the softening only occurs in a small temperature range near the melting point. Once the temperature is reached, flow starts.
The most common types of PA are PA6, PA66, PA610, PA11, PA12, PA1010, PA612, PA46, PA6T, PA9T, MXD-6 aromatic amide, etc. There are numerous other types of PA as well. Most frequently, PA6, PA66, PA610, PA11, and PA12 are used.
Engineering plastics made of nylon have the appearance of horny, tough, white (or milky white), transparent, or translucent crystalline resin that can be painted any color. Nylon’s molecular weight as an engineering material typically ranges from 15,000 to 30,000. They have a density of 1.14–1.15 g/cm3, which is somewhat higher than 1. Over 60.0 MPa in tensile strength. > 30% elongation. 90.0 MPa of bending strength. Impact strength notched: (kJ/m2) >5.
Nylon shrinks between one and two percent. Keep an eye out for dimensional changes brought on by the molding process absorbing moisture. The rate of water absorption is 100%. When the relative moisture absorption is saturated, it can absorb 8%. The temperature range for use is -40 to 105 °C. 215–225°C is the melting point. A 23.5mm wall thickness is appropriate. Water acts somewhat as a plasticizer for PA since the mechanical characteristics of PA, such as tensile and compressive strength, fluctuate with temperature and moisture absorption. Its tensile and compressive strength can be increased by adding glass fiber. The temperature resistance is also enhanced by around two times. PA can be used constantly without lubrication because of its extremely high wear resistance.You can add sulfide to PA to create a particular lubricating effect.
Principal Benefits of PA Performance
1. High tensile and compressive strength, good toughness, and mechanical strength. Although it has a specific compressive strength that is comparable to metal and a higher specific tensile strength than metal, it is less stiff than metal. The tensile strength is more than twice as great as ABS and is very similar to the yield strength. It has a considerable capacity for impact and stress vibration absorption, and its impact resistance is superior to that of acetal resin and much higher than that of common plastics.
2. The components exhibit exceptional fatigue resistance; even after numerous twists and spins, they can keep their initial mechanical strength. In situations where the cyclic fatigue effect is very noticeable, such as in modern bicycle plastic rims and popular escalator handrails, PA is frequently employed.
3. High heat distortion temperature and heat resistance (such as nylon 46, etc.; highly crystalline nylon can be utilized at 150 degrees for an extended period of time). The heat distortion temperature of PA66 after glass fiber reinforcement is greater than 250 degrees.
4. The surface is smooth, has a low coefficient of friction, and is resistant to wear. When employed as movable mechanical components, it possesses self-lubricating qualities and is quiet. When the amount of friction is not too great, it can be used without lubricant. Water, oil, grease, and other lubricants can be used if they are actually required to minimize friction or assist in the heat transfer process. As a result, it serves the purpose of a transmission component for a long time.
5. The material is corrosion-resistant, extremely resistant to alkali and the majority of salt liquids, as well as resistant to mild acids, motor oil, gasoline, aromatic hydrocarbons, and common solvents. However, it is not resistant to strong acids or oxidizers. It has strong anti-aging properties and can withstand corrosion from gasoline, oil, fat, alcohol, weak alkali, etc. It can be utilized as a lubricating oil, gasoline, and other packing material.
6. It has excellent antibacterial and antifungal properties, is self-extinguishing, non-toxic, odorless, weather resistant, and inert to biological deterioration.
7. Possesses superior electrical qualities. high-quality electrical insulation. Both the volume resistance and the breakdown voltage resistance of nylon are high. In dry settings, it can be utilized as a power frequency insulating material. Even in conditions with high humidity levels, it still offers good electrical insulation.
8. The components are lightweight, dyeable, and formable. It can flow swiftly due to the low viscosity of the melt. It can be swiftly shaped, is simple to fill the mold with, and has a high solidification point after filling, all of which contribute to a short molding cycle and good production efficiency.
PA performance’s main drawbacks
1. Absorbs water readily. It absorbs a lot of water; saturated water levels can exceed 3%. Particularly the thickening of thin-walled components, it somewhat impacts the dimensional stability and electrical qualities. The mechanical strength of the plastic will be significantly reduced as a result of water absorption. The impact of the usage environment and the correctness of the component matching should be taken into account while choosing materials. Fiber reinforcement can decrease the resin’s water absorption, enabling it to function in hot and humid conditions.A strong affinity exists between nylon and fiberglass. Combs, toothbrushes, laundry hooks, fan ribs, mesh bag ropes, fruit packaging bags, and other items are frequently made from it. When in prolonged contact with acids and alkalis, it is not hazardous. It is important to note that adding glass fiber can raise nylon’s tensile strength by nearly two times while also improving its temperature resistance.
2. A weak resistance to light. It will experience oxidation with oxygen in the air in a prolonged high-temperature environment. The base surface will initially become chipped and cracked, and the hue will initially turn brown.
3. Intravenous Molding technology has stringent requirements: the product’s dimensional stability is difficult to control due to thermal expansion; the product’s presence of sharp corners will cause stress concentration and reduce mechanical strength; wall thickness; and even minute amounts of moisture will significantly harm the molding quality. If it is uneven, the product will be distorted and deformed; during the product’s post-processing, high equipment accuracy is needed.
4. It will swell after absorbing alcohol and water. It cannot be utilized to make materials that are acid-resistant since it is not resistant to strong acids and oxidants.
The material modified nylon PA6/66 is used for
The automotive, electrical and electronic, transportation, industrial production, wire and cable communication, film, and daily-needs industries all use nylon extensively. Numerous bearings, circular gears, cams, bevel gears, oil pipes, oil reservoirs, protective covers, support frames, wheel covers, deflectors, fans, air filter housings, radiator water chambers, brake pipes, engine hoods, and door handles are among the products it makes. Bearings, gears, pulley pump impeller, blades, high-pressure sealing rings, pads, valve seats, bushings, ropes, transmission belts, grinding wheel adhesives, battery boxes, electrical coils, cable joints, a variety of rollers, pulleys, pump impellers, fan blades, worm gears, propellers, screws, and more. Casings, hoses, cable sheaths, shears, pulley sets, planer slides, solenoid distribution valve seats, cold aging equipment, liners, bearing cages, automobiles and tractors, as well as oil-resistant gaskets and containers Different oil pipes, pistons, ropes, transmission belts, textile machines, zero-mist industrial equipment, etc.
