Many people may not yet have an in-depth understanding of PK material itself. As one of WDF
’
s key products, let us take this opportunity to explore and gain a deeper understanding of the unique characteristics of PK.
A New-Generation Green Engineering Material
As one of WDF’s key products, PK material has attracted increasing attention due to its unique molecular structure and excellent overall performance. Perhaps many people still do not have an in-depth understanding of PK. Therefore, let us get to know this material again — a material combining “green environmental protection” and “innovative potential”.
Understanding PK — Composition and Structure of PK
PK (Polyketone) is a polymer produced through the terpolymerization of carbon monoxide, ethylene, and propylene. It is a green and environmentally friendly material with diverse performance characteristics, featuring a main chain composed only of C-C bonds.
Understanding PK — Basic Properties of PK Material
The specific gravity of PK material is: 12% lower than POM, 6% lower than PBT.Its molecular structure determines its excellent toughness and impact resistance. Under different conditions, its mechanical strength changes little, and its performance stability is superior to other conventional engineering plastics.
PK Characteristics — Excellent Hydrolysis Resistance
Hydrolysis refers to the degradation phenomenon that occurs when materials come into contact with water or water vapor, which usually leads to a decrease in material strength, rigidity, and durability. Compared with traditional plastics, PK material demonstrates stronger resistance to water absorption and hydrolysis.Compared with nylon, PK is less sensitive to humidity and is suitable for components exposed to water.
PK Characteristics — Wear Resistance & Low Noise
PK features outstanding wear resistance, with wear performance up to 14 times that of POM.
It also provides long-term dimensional stability, and its strength is less affected by humidity.These advantages enable PK to be used in applications such as pulleys, gears, and bearing bushings. Compared with traditional materials such as POM and nylon, PK is more suitable for solving issues including wear debris generation, gear tooth breakage, and noise reduction.
Wear / Noise Test
PK vs. POM: Comparison of Low Wear and Low Noise Performance
Ring-on-ring test: (100 rpm, 66 N)
Cooling Fan Engineering Specification — Noise Test
Compared with PA66+GF/MF, PK+GF demonstrates lower noise levels (5 dB difference).
Due to its relatively low glass transition temperature (approximately 10°C), PK provides excellent vibration damping performance under different rotation speeds.
Theoretically, materials with low Tg, high mass, and low stiffness have higher damping effects.
PK Characteristics — High Impact Resistance
Under low-temperature conditions, PK material demonstrates excellent impact strength compared with PBT material.
Sample photos after impact testing at -30℃:
PK Characteristics — Excellent Chemical Resistance
Polyketone is one of the plastics with excellent chemical resistance and can effectively resist the attack of various chemicals.
Its main chain consists of C-C segments, enabling it to maintain excellent stability when exposed to chemicals such as acids, alkalis, salts, and solvents (except strong acids and strong alkalis).
Its chemical resistance is comparable to PPS, providing higher safety and durability in complex chemical environments.
After immersion in 38% H2SO4 for 24 hours:
The PA66 GF30 sample strip (left) shows degradation, while the PK GF30 sample strip (right) remains unchanged.
PK Characteristics — Excellent Barrier Performance
PK can effectively block water, oxygen, and organic substances, demonstrating excellent barrier and sealing performance.
Its barrier effect is comparable to EVOH.
PK Characteristics — Low VOCs
Due to PK’s unique production process and environmentally friendly formulation, very few small molecules are generated or released.
It does not contain pentachlorophenol* and meets low VOC standards required by various automotive manufacturers worldwide.
Meanwhile, thanks to its low odor characteristics, PK can easily pass odor tests such as VDA 270.
It is suitable for automotive interior applications and provides a safer and more environmentally friendly solution compared with materials such as POM and ABS.
PK Characteristics — Excellent Dimensional Stability
PK shows minimal dimensional changes after moisture absorption or water absorption：
PK Characteristics — Low Carbon & Environmental Protection
Most environmentally demanding applications are related to water-contact fields；
OM cannot be used in some applications due to formaldehyde emission concerns.
PA applications may be limited due to dimensional stability and hydrolysis stability issues.
PK can be used in food-contact and medical applications and meets toxicity and biocompatibility certification requirements.
Its excellent barrier properties can effectively extend food shelf life during storage.
Its extremely low VOC emissions provide enhanced safety.
Polyketone is an environmentally friendly engineering plastic suitable for water-contact, food-contact, and medical-related applications. It has obtained relevant food-contact certification reports.
Based on years of research and development of PK formulations, WDF has developed more than 100 grades, including:
- Glass fiber reinforced grades
- Carbon fiber reinforced grades
- Mineral-filled grades
- Wear-resistant grades
- Low-warpage grades
- Flame-retardant grades
- Food-grade grades
- Thermally conductive grades
WDF has established its proprietary brand INNOKETONE® and obtained third-party certifications including:
- CQC
- UL Yellow Card
- Food-contact certifications
- Drinking water contact certifications
Application Examples——INNOKETONE® PK
If you look closely, PK materials can be found in structural components across various industries, including home appliances, new energy, electric vehicles, intelligent robots, packaging, kitchenware, medical applications, and more.
PK has already been playing an important role around us, quietly helping create a more convenient and comfortable living environment.
Meanwhile, with continuous technological development, PK demonstrates many advantages compared with traditional materials and has become a new material choice, such as:
1 Automotive Applications
Advantages:
- Impact resistance
- Wear resistance
- Safety and environmental protection
- Heat resistance
- Chemical resistance
- Hydrolysis resistance
- Elastic recovery
Applications:
· Electronic water valves
· Integrated flow plates
· Connectors
· High-voltage battery connection plates
2 Wear-Resistant Components
Advantages：
· Impact resistance
· Wear resistance
· Heat resistance
· Chemical resistance
· Elastic recovery
Applications:
· Gears
· Bearing bushings
· Helmet protective components
· Rod centralizers
3 Food Contact Applications
Advantages：
· Impact resistance
· Wear resistance
· Safety and environmental protection
· Heat resistance
· Chemical resistance
· Hydrolysis resistance
· Elastic recovery
Applications:
· Food conveyor belts
· Pipe fittings
· Coffee machine components
· Cutting boards
4 Toy Applications
Advantages：
· Impact resistance
· Wear resistance
· Safety and environmental protection
· Heat resistance
· Chemical resistance
· Elastic recovery
Applications:
· Toy frames
· Wear-resistant toy components
5 Packaging Applications
Advantages：
· Impact resistance
· Wear resistance
· Safety and environmental protection
· Chemical resistance
· Hydrolysis resistance
· Barrier performance
· Elastic recovery
Applications:
· Cosmetic packaging
· Pumps
6 Water Contact Applications
Advantages：
· Safety and environmental protection
· Chemical resistance
· Hydrolysis resistance
· Elastic recovery
Applications:
· Water purifier components
· Water meters
7 Cleaning Appliance Applications
Advantages：
· Impact resistance
· Wear resistance
· Heat resistance
· Chemical resistance
· Hydrolysis resistance
· Elastic recovery
Applications:
· Floor cleaning machine components
· Robot vacuum cleaner components
8 Pipe Applications
Advantages：
· Impact resistance
· Wear resistance
· Heat resistance
· Chemical resistance
· Hydrolysis resistance
· Elastic recovery
Applications:
· Oil & gas pipelines
· New energy cooling pipes
From structure to performance, from daily life to engineering applications, INNOKETONE® PK material is demonstrating unlimited possibilities through its excellent characteristics. WDF continues to explore improved-performance and lower-carbon modification solutions, enabling materials to meet functional requirements while better supporting sustainable development. In the future, WDF will continue to drive innovation, explore the potential of PK materials in more green application fields, and work together with partners to create a sustainable future.
