Do you know what makes nylon plastic injection molding so useful and effective? Its due to its beneficial properties and unique materials. Read below for the details on why it’s a good choice.
There are several reasons to consider Nylon Plastic (PA) injection molding due to the benefits offered by these materials.
These benefits stem from the chemical composition of this plastic material, thereby making it a cheaper alternative to other materials.
Moreover, Nylon Plastic has excellent molded-in properties including strength and providing visual aesthetics to the product formed. That being the case, manufacturers need to consider the use of this polymer in the creation of their product.
What is Nylon Plastic (PA)?
Nylon plastic (PA) is a synthetic thermoplastic polymer that is used in injection molding applications. PA was produced by American chemist Wallace Carothers in 1935 while working at the DuPont research facility in Delaware.
On the other hand, PA is a durable, versatile, and flexible material, and it serves as a cheaper alternative to materials including rubber, silk, and latex. It is commonly available in black, white, and off white or beige color.
When it comes to injection molding, a nylon’s tensile strength can be increased by filling it with glass fibers. The percentage of these glass fibers usually range between 10% and 40%.
However, it is worth noting that glass fibers may impact on the way the part fails. For instance, nylon has great bending strength, and the absence of glass fills means that the nylon will bend and yield before there is a breakage.
In contrast, glass fibers will lead to an instantaneous breakage of the part with very little bending occurring.
Properties of Nylon Plastic
Some properties of Nylon plastic are:
- Name Nylon (PA), or Nylon Polyamide
- Specific Gravity: 1.13
- Tensile Strength: 11,000 psi
- Melting Point: 220°C (428°F)
- Flexural Modulus: 16,000 psi
- Hardness Level (Rockwell) R115
- Chemical Formula: [NH−(CH2)5−CO]n
- Shrink Rate: 1.3 – 1.7 % (.013 – .017 in/in)
- Impact Strength: 0.6 fit-lb/in notched Izod
- Typical Injection Mold Temperature: 54 – 93 °C (130 – 200 °F)
These properties of nylon have increased their demand, which first began during World War II when silk, rubber, and latex were scarce.
Uses of Nylon
Nylons is a part of everyday life since they are in use with a variety of applications. Their impressive mechanical and electrical properties, wear resistance and chemical resistance has given them several use cases.
As such, they have versatile uses which have helped in the creation of products including:
- Fishing line
- Medical products
- Consumer footwear
- Fabric and clothing
- Food packaging films
- Automotive products
- Filament for toothbrushes
- Fiber for threads and ropes
- Sports and recreation equipment
- Reinforcement in rubber material such as car tires
- Injection-molded parts for or vehicles and mechanical equipment
Reasons to Use Nylon Injection Molding
The benefits of nylon injection molding are some of the reasons why it is needful to use it in injection molding.
Some of these benefits include:
- Low friction
- High tensile strength
- High melting temperature
- Resistance to chemicals and abrasions
- Ease of combination
1. Low Friction
The chemical composition of nylon prevents it from heating up easily when it is used in high friction applications. Therefore, this material has a low coefficient of friction which is extremely beneficial in injection molding.
Specifically, it can also be used in applications such as slides, gears, bushings, and plastic bearings.
What’s more, this material may not be the most slippery plastic, but it has high performance in terms of chemical, thermal, and mechanical properties which makes it ideal for parts that may wear easily.
2. High Tensile Strength
The combination of nylon with other materials helps to improve its tensile strength and other qualities. An instance is the filling of nylon with glass fibers which makes the resultant plastic less flexible and more brittle.
Thus, it helps to improve a nylon’s tensile strength which makes it suitable in injection molding applications.
Specifically, the resultant tensile strength from the combination can be 70 percent greater than standard nylon.
Nylon is sometimes a substitute for low strength metals.
It has become an ideal component in the engine compartment of vehicles which can be largely tied to its strength, chemical compatibility, and temperature resilience.
3. High Melting Temperature
Nylon has a high melting point due to its chemical composition.
The high melting point of this material makes it an excellent alternative to metal components that are suitable for use in high-temperature environments. For example, under the hood of a car.
Some of these environments are different types of high-friction machinery including car engines.
On the other hand, nylon plastic melts to liquid instead of burning, and as such, it can be melted and remolded or recycled into other parts.
4. Resistance to Chemicals and Abrasions
Plastic is exceptionally strong and resistant to abrasions and moisture absorptivity.
This material is also resistant to chemicals which makes it long-lasting.
5. Creation of Products
When it comes to plastic injection molding, PA can be cast to form plastic bearings, gears, bushings, and several other components.
These components have found use in cases of mechanical equipment including engines.
6. Ease of Combination
Nylon can be combined with other materials easily to improve their strength.
An example is the use of glass fills on it.
Limitations of Nylon
Despite the benefits, it is important to point out that a strong processing approach is necessary when using the material to prevent variations and defects.
On the other hand, Nylon has a limitation despite the benefit it offers. In this case, it’s a flammable material that tends to burn easily when exposed to open flame.
However, flame retardants can be added to Nylon in a bid to improve its flammability.
Over and above that, ultraviolet rays can also impact on the quality of nylon, negatively, hence, it is not advisable to place them under direct sunlight.
Nonetheless, an ultraviolet stabilizer is sometimes added to the plastic material prior to injection molding.
Conclusion
The properties offered by Nylon Plastic are some of the reasons to consider its use in injection molding.
They have a high melting point, low friction, high tensile strength due to their chemical composition.
And most importantly, they are an affordable alternative to the use of metallic parts that are also suitable in high-temperature environments.
That being the case, as a manufacturer looking for cheaper thermoplastic polymers whose chemical composition can offer several benefits, nylon plastic injection molding is a good choice.
