Polyketone: The Superior Resin

After a nearly 20 year hiatus, aliphatic polyketone is back on the market commercially. Re-introduced under the POKETONE® brand by Hyosung in 2015. Polyketone is a semi-crystalline polymer that combines:

  • the higher heat performance of polyamide 6 and 6/6
  • fuel resistance of nylon 11 and 12
  • the low moisture absorption of PBT
  • the exceptional wear & friction performance of POM

Polyketone is solving application problems and delivering improvements over these other resins.

Many of our customers ask what makes polyketone such a superior plastics option for so many injection molding needs.

Read on to learn about the advantages of polyketone and some frequently asked questions.

Polyketone Key Advantages

  • Higher temperature resistance than POM and PBT
  • Polyketones have high impact strength (2.5x stronger than POM & PBT)
  • Low moisture absorption
  • Stable mechanical properties over a wide range of humidity
  • Excellent dimensional stability in hot/wet environments
  • Exceptional chemical & barrier resistance to motor fuels (10x to PA11 & PA12)
  • Flame retardant grades include non-halogen and low smoke generation options
  • Very low coefficient of friction rate and superior wear resistance
  • NSF and FDA compliant for drinking water and food contact
  • High cyclic fatigue strength
  • Fast cycling / reduced molding cycle time
  • A package of features & benefits that results in a very cost competitive resin

As you can see, a number of important differences make polyketone ideal for manufacturing components for automotive, electrical/electronic, material handling and in other industries. Customers are using polyketone for the production of under the hood electrical connectors, fuel pump modules, vehicle wheel covers, golf equipment, and conveyor components.

Polyketone resin is processed by injection molding, powder coating, and extrusion.

The Injection Molding Industry’s Choice

When it comes to injection molding, polyketone holds a significant benefit over traditional materials such as nylons, acetal and polyester for cycle time, ease of drying, no off gassing and no need to rely on moisture for toughness. Polyketone exhibits similar mold shrinkage to these resins allowing for existing molds to be used.

Let’s take a look at some of the limitations of some of the most commonly used materials:

  • Polyamide (nylon) resin. Nylon tends to vary in size and dimension because it absorbs moisture and swells like a sponge when wet. Likewise its mechanical properties vary greatly with the degree of moisture uptake.
  • Polyacetal. Polyacetal tends to squeak and make noise when used in a sliding or rotating components, particularly against another plastic. But polyketone’s more optimal surface quality makes for a noticeably quieter process. POM is well known for its potential to produce noxious gases during melt processing.
  • PBT polyester. Polyketone is also a suitable replacement for PBT polyester as it is tougher and can withstand wet environments and offers much superior frictional performance.

Frequently Asked Questions


Can Polyketone easily replace today’s commonly used plastic materials?

Yes! Polyketone is a drop-in replacement for these materials because they are all semi-crystalline resins and exhibit a similar mold shrinkage during processing. So polyketone can be molded in existing tooling which enables a solution without having to purchase and build new molds (a big savings, too).

And with polyketone, you don’t need to retool the die to run a sample.

What common manufacturing headaches does polyketone solve?

Polyketone is what we call “processing friendly,” and it’s a clear winner compared to polyacetal. Unlike polyacetal, which produces formaldehyde gas—a hazardous material—polyketone doesn’t generate any fumes, odor or gas during processing.

Polyketone outshines nylon as well due to nylon’s tendency to absorb moisture and swell in humidity. This means if nylon is produced in one region of the world and sent to another region with a different humidity level, its shape and size will change.

Conversely, polyketone holds the same size and fit regardless of where it is produced and where it is sent. So for tight tolerance demanding applications, polyketone is the material of choice.

Is polyketone a cost-effective solution?

Absolutely. Polyketone wins hands-down when it comes to cost. Some manufacturers explore the use of high performance nylon (for example, PA11 and PA12) as an alternative material because of its lower moisture absorption than standard nylons. Polyketone competes effectively with PA11 and PA12 on moisture absorption and dimensional stability but clearly stands out with a much lower cost. Polyketone is 5x less expensive than PA11 and PA12 and 2x the heat resistance.

Contact Us Today. We’ll Help You Find the Right Solution!

If you’re molding parts in POM, nylons or PBT and are having issues, contact PolySource today and we’ll assist on determining the best polyketone grade to consider for your application.