Top 7 Resins Used in Injection Molding You Didn’t Know Were There


1) Polyethylene (PE).

Polyethylene is one of the most common resins used for injection molding because it’s a versatile material and fairly inexpensive. This plastic can be used to create products ranging from toys to grocery bags. Some types of polyethylene include low-density polyethylene (LDPE) and high-density polyethylene (HDPE). One benefit of polyethylene is that it’s resilient, which means it can withstand wear and tear better than other materials. The durability makes it ideal for products with a long lifespan.  PPO: Polypropylene is another popular resin used for injection molding. It has a low melting point, making it very easy to work with, but also lower strength than other plastics like ABS or PVC. PPO has good insulation properties and excellent chemical resistance so you’ll often find this material in food containers or car parts.


2) Polypropylene (PP).

Polypropylene is a versatile resin that is used to produce a wide variety of products. It has high clarity, good gloss, and excellent chemical resistance for both basic and acidic solutions. Polypropylene can also be heat-welded, glued or welded with other polymers such as polyethylene or polystyrene. The disadvantage of PP is its brittleness at low temperatures and its high melt viscosity which creates problems with injection moldability. One way to increase the mechanical strength of PP is through crystallization (heating the material until it hardens). Its superior wear characteristics make it perfect for items subjected to harsh use like outdoor furniture and sporting goods equipment. Polyurethane (PU): As an alternative to ABS, polyurethane offers improved tensile strength but poorer surface hardness than ABS . Lower production cost due to less plasticizer requirement are other benefits when using PU compared with ABS.


3) Polystyrene (PS)

Polystyrene is one of the most common resins used for injection molding, because it’s inexpensive, readily available and can be recycled. Polystyrene is also a thermoplastic resin, which means that it can be melted down and then cooled to create rigid parts with low-stress strength. Polystyrene can be used for both high and low-volume production runs.

Polymers are made up of long chains of molecules called monomers which are bonded together through covalent bonds.


4) Polyvinyl chloride (PVC).

PVC is one of the most common resins used for injection molding. The material is ideal because it’s lightweight, easy to work with, and inexpensive. It’s also a great choice if you want your product to be resistant to water or chemical spills. Acrylonitrile-butadiene-styrene (ABS): ABS is an economical plastic that can handle higher temperatures than many other types of plastic resin.


5) ABS.

The resin used most often for injection molding is ABS, which stands for Acrylonitrile Butadiene Styrene. It’s a thermoplastic resin with good chemical resistance and wear resistance, and is easy to color. The downside is that it’s relatively brittle, so it needs to be handled carefully during the manufacturing process. ABS is also sensitive to moisture and can warp or lose its shape when exposed to high humidity levels.

It’s not as easily recyclable as other plastics because of these characteristics.

The strength of ABS varies from around 700-900 PSI depending on how much coloring agent you use.


6) Nylon.

Nylon is a synthetic polymer made from the chemical compound called acrylonitrile, which is obtained as a by-product of the production of acrylic acid. It is also produced from coal or petroleum products. Nylon was developed by Wallace Carothers at DuPont’s research facility at Wilmington, Delaware in 1935.

Nylon resins are made up of several different copolymers.


7) Polycarbonate (PC).

Polycarbonate is a thermoplastic resin and belongs to the family of polyesters. Polycarbonate is considered one of the most versatile resins available. PC has excellent impact resistance and can be used with polar solvents, strong acids and bases. Polycarbonate can also be used for gas-tight applications, because it can withstand temperatures up to 140 degrees Celsius without significant degradation.