Which materials are available for injection moulding?
Standard materials at Nordmould are ABS, PC, PMMA, PP, POM, TPE, and TPU — covering most enclosure, structural, optical, and flexible-part requirements. Engineering grades and glass-filled variants are available on request. Production runs start from 100 pieces across all material options.
What plastics are commonly used in injection moulding?
Material choice drives every downstream decision: wall thickness, gate placement, shrinkage compensation, and surface finish. The right call depends on mechanical requirements, operating environment, and cosmetic spec.
- ABS (Acrylonitrile Butadiene Styrene): The default for enclosures and consumer electronics. Good impact resistance, consistent shrinkage around 0.4–0.8%, easy to paint or texture. Continuous service to about 80°C.
- PP (Polypropylene): Best-in-class for chemical resistance and living-hinge fatigue life. Higher shrinkage (1.8–2.5%) means gates and wall uniformity matter more than with ABS. Continuous service to 80–100°C depending on grade.
- PC (Polycarbonate): High-impact clarity — light transmission around 88–90%. The go-to for lenses, safety covers, and medical enclosures. Continuous service up to approximately 130°C. Requires careful drying before processing to prevent splay.
- PMMA (Acrylic): Higher optical transmission than PC (up to 92%), inherently UV-stable without additives. Brittle by comparison — notch sensitivity is a design risk. Shrinkage is low at 0.2–0.6%, giving good dimensional stability in optical parts.
- POM (Acetal): The standard choice for gears, sliding contacts, and precision mechanical parts. Low friction coefficient, tight shrinkage control (1.8–2.3%), and continuous service to 90–100°C. Sensitive to sharp internal corners — stress concentrations cause cracking.
- TPE/TPU (Thermoplastic Elastomers/Polyurethanes): Flexible, rubber-like materials processed on standard injection machines. TPU carries higher abrasion resistance and tensile strength than commodity TPE grades; both are used for grips, seals, and over-moulded components.
When should you choose specific injection moulding materials?
| Material | Primary Property | Typical Application |
|---|---|---|
| ABS | Impact Strength | Enclosures, handheld devices |
| PP | Chemical Resistance | Laboratory equipment, caps |
| PC | Optical Clarity + Heat | Lenses, light pipes, medical |
| PMMA | UV Stability | Outdoor signage, light covers |
| POM | Low Friction | Precision gears, sliding parts |
| TPE | Soft Touch | Over-moulded grips, seals |
| TPU | Abrasion Resistance | Industrial gaskets, wheels |
How do different moulding materials compare in performance?
The table below shows typical property ranges for standard grades. Glass-filled or high-heat variants will differ significantly — confirm with Nordmould's technical team during the DFM review.
| Property | ABS | PC | PP | POM | TPE |
|---|---|---|---|---|---|
| Tensile Strength | 40–50 MPa |
60–70 MPa |
30–40 MPa |
60–75 MPa |
10–25 MPa |
| Max Service Temp (continuous) | ~80°C |
~130°C |
80–100°C |
90–100°C |
60–120°C (grade-dependent) |
| Shrinkage Rate | 0.4–0.8% |
0.5–0.7% |
1.8–2.5% |
1.8–2.3% |
0.5–2.5% |
| Impact Resistance | High | Very High | Medium | Medium | Very High |
| Clarity | Opaque | Transparent | Translucent | Opaque | Translucent/Opaque |
In-depth material guides
Each material has a full technical guide covering properties, grades, processing parameters and design rules:
- ABS injection moulding — impact-resistant, general-purpose housings
- Polypropylene (PP) — chemical resistance and living hinges
- Polycarbonate (PC) — high-impact optical clarity
- POM / acetal — low-friction precision mechanical parts
- PMMA / acrylic — optical clarity and UV stability
- Nylon (PA6, PA66) — tough, abrasion-resistant engineering parts
- Polyethylene (HDPE, LDPE) — chemical-resistant and low-cost
- Polystyrene (GPPS, HIPS) — rigid and dimensionally stable
- TPE — soft-touch over-moulding, grips and seals
- TPU — abrasion-resistant flexible parts
What surface finishes are available for injection moulded parts?
Nordmould provides three standard finish categories. Finish is set at tooling stage — changing it after tool-cut means re-polishing or re-texturing, which adds cost and lead time.
- Matt: A non-reflective surface achieved with stone or bead-blasted tooling (SPI C or D grades). Hides weld lines and minor surface imperfections well. Standard for industrial components and internal housings.
- Glossy: A smooth, semi-reflective finish produced by sandpaper or fine-stone polishing of the tool steel (SPI B grade). The baseline spec for most consumer-facing parts.
- High-gloss: A mirror-like finish requiring diamond buffing of hardened steel tooling (SPI A grade). Used for optical parts or premium aesthetic components in PC or PMMA. Adds approximately 1–2 weeks to tooling lead time due to the manual polishing involved.
Custom textures — VDI or Mold-Tech standards — can be applied to tooling on request.
Nordmould confirms the right material and finish combination during the free DFM review.
Frequently asked questions
What are the most common injection moulding materials?
The most common materials at Nordmould include ABS for general-purpose housings, Polypropylene (PP) for chemical resistance, and Polycarbonate (PC) for high-impact transparency. We also offer specialised elastomers like TPE and TPU for flexible parts, and engineering-grade POM for high-stiffness mechanical components.
Can Nordmould source engineering-grade plastics on request?
Yes, while our standard range covers ABS, PC, PP, PMMA, POM, TPE, and TPU, Nordmould can source specific engineering-grade resins and glass-filled composites upon request. Our technical team assists in selecting the appropriate material grade during the DFM review process to ensure part performance.
Which material is best for high-gloss surface finishes?
For high-gloss or optical applications, Polycarbonate (PC) and PMMA (Acrylic) are the preferred choices. These materials exhibit excellent clarity and flow characteristics, allowing them to take on a high-gloss finish when used with polished, high-quality steel tooling.
Are materials at Nordmould suitable for low-volume production?
Yes, all materials in our standard catalogue are available for orders starting from 100 pieces. Nordmould specialises in making professional-grade plastics accessible for low-to-mid volume series, bridge tooling, and rapid prototyping using both soft and hard tooling options.
How do I choose between TPE and TPU for flexible parts?
TPE is typically selected for its soft-touch feel and ease of processing, often used in over-moulding applications. TPU is preferred when the part requires higher abrasion resistance and superior mechanical strength. Nordmould provides guidance on selecting between these elastomers based on the end-use environment.
Request a free DFM review to confirm material compatibility for your project.