You have a new project coming up and want to get your latest invention to market in record time. You’re unsure if you want to fund the design and testing for a new resin specific for your project. Perhaps there is a popular resin currently available on the market that can meet all of your durability and environmental concerns plus have sufficient quantities in a stable supply chain over the next few years. Does that sound familiar? If so, you need to know what is currently available. We have gathered the 10 most popular plastic pellet resins currently being used in many industries, which will help you select one for your next project.
How to Select Your Next Resin
Every plastic resin will exhibit specific attributes and properties that may make it somewhat close to what you need for your project. There are thousands of resins available on the market, and finding the exact one can be an exhausting venture. The key to narrowing down the variables is deciding which properties your resin should have. These are just a few of the main considerations to stay focused on:
- Hardness / Stiffness – hardness measures the resistance to indentation when direct force is applied to the formed part. You will need to decide if your parts can be soft and have indentation or deflection or they should be extremely hard and resist forces applied.
- Flexibility – Flexibility allows your parts to bend without breaking when force is applied.
- Weight – Weight has ties to the density of the resin. Your base resin will be measured with density as it relates to the amount of resin used in the part. A larger density will attribute to a higher weight of the parts, so if you want a lighter part you will want to look at lower densities.
- Cost – Cost is typically a large factor for profitability of a new product. You may have to weigh cost versus supply chain availability, ease of molding production, and other properties mentioned.
- Environment – The environment your product is used in can make a big difference on the resin you need to select. Does it have exposure chemicals, varying temperatures, and large pressure swings? Each of these can change the base resin you select.
What are the 10 Most Popular Resins in Use Today?
There are a handful of resins that are commonly used for many products you’ll find on the market regardless of the industry it comes from. Beyond these resins, there are hybrid combinations that bridge the gap to utilize the resin strengths without showing the individual limitations. Think of it as the best of both worlds. These are the ten most popular resins between common and hybrid resins that we use in our operations:
Acrylonitrile Butadiene Styrene (ABS) – ABS is a very common thermoplastic resin that offers a tough exterior with thermal stability. It offers added benefits of lower cost, it can be colored to match any component or visual design requirement, and it can be further processed as needed (such as machining into a specific shape). It can be found in many industries including automotive, aerospace, and commercial and home manufacturing. ABS is thermally stable but shouldn’t be selected for extreme temperatures above 200 F. It also does not have superb chemical resistance. It can withstand some chemical exposure but won’t last in extremely corrosive environments.
Nylon – Nylon has been in use for eight decades and doesn’t show any signs of going out of style. It’s commonly used is fabrics and carpets, food packaging, and automotive components. One of its drawbacks is corrosive environments. It should not be chosen if it can come in contact with harsh acids or fire.
Polypropylene (PP) – Polypropylene offers excellent chemical resistance, flexibility, and electrical insulation. It is commonly mixed with additives for the automotive industry, plus it is heavily used in packaging, electrical manufacturing, common household appliances, toys and games, and medical products. Polypropylene is flammable and can degrade under ultraviolet light (UV) exposure without additives to make it non-flammable or UV protected. It can be used in many harsh environments, but only with additives chosen for the application.
HIPS (High-Impact Polystyrene) – HIPS offers impact resistance, dimensional stability, and surface characteristics for secondary machining or other aesthetic properties. It can also be glued or bonded together too. HIPS offers low cost, which makes it a favorite choice for injection molding. HIPS can be flammable, so be sure to verify your environmental application before selecting it as your material choice.
Polycarbonate – Polycarbonate offers excellent strength at a medium level cost. It is a high-grade thermoplastic that also is naturally transparent. It makes for a great option for safety wear, bulletproof glass, and medical uses including test tubes, beakers, and pipettes. PC is not flexible naturally, nor does it mix well with dyes to create custom colors. If it is selected for food grade materials, it must also be BPA-free.
Low-Density Polyethylene (LDPE) / High-Density Polyethylene (HDPE) – Polyethylene offers superior moisture resistance, chemical resistance, high impact strength, as well as being a cost-effective alternative. The density of each contributes to the flexibility of the finished material as well as how it reacts to other environmental concerns. You can find both versions being used in household goods and appliances, medical applications, electrical wiring, computer components, food packaging products, toys, agricultural products, home and professional furnishings, and more.
Acrylics (PMMA) – Poly(methyl methacrylate), also known as Acrylic or PMMA, is a plastic resin commonly used in applications to replace glass. It is transparent, has excellent chemical resistance, a hard exterior, and is very dimensionally stable. Acrylic is low cost with a strong supply available on the market.
Polyetheretherketone (PEEK) – PEEK is a high-performance plastic that offers extreme resistance to harsh chemicals and corrosive environments. It can also withstand extremely hot and humid environments without degradation. It can commonly be found in industrial applications including manufacturing and chemical processing. PEEK is also a good option for the automotive and aerospace industries, plus you can find it used in specialized medical components like implants.
Acetal/ Polyoxymethylene (POM) – Acetal or polyoxymethylene offers exceptional hardness, excellent wear resistance, and chemical resistance. It is also a good choice for addition of specialized colors. Acetal won’t absorb moisture as other resins will, which makes it excellent for the food and beverage industries. It can also be found in products in the automotive sector and household appliances.
Thermoplastic Polyurethane (TPU) – TPU has properties opposite on many of the earlier mentions. It exhibits soft and elastic properties similar to a rubber-like elasticity. It is used primarily cable insulation, electrical tools, and sports gear because it can withstand high temperatures.
Choosing the perfect resin doesn’t have to slow your design process down. You should be including discussion points on the function, environment, quantity, and recycling of your product to ensure the best resin is chosen for your product. The 10 common resins listed are just a small fraction of what is available, and many can be combined to create a hybrid resin with the best properties from each selection. SEA-LECT Plastics has an elite team that produces world-class prototypes and products, and we have decades of experience with plastic injection molding. We can offer support to determine what type of mold you need, what resin to choose, and how to best invest in your future. Give us a call at (425) 339-0288 or email us at mattp@sealectplastics.com. We’ll help to determine the best manufacturing for your next project.
Matthias Poischbeg was born and raised in Hamburg, Germany. Matt moved to Everett, Wash., after finishing his bachelor’s degree in business in 1995 to work for Sea-Dog Corporation, a manufacturer, and distributor of marine and rigging hardware established in 1923.
In 1999, Matt took over the reins at Sea-Lect Plastics Corporation, a sister company of Sea-Dog and a manufacturer of plastic injection molded products with an in-house tool & die shop. Matthias Poischbeg is also a contributor to Grit Daily.