Material selection on a moulded toy is usually settled by default rather than by decision, and the default is often ABS because it is what the last factory used. This guide compares the three common toy materials on the properties that actually decide failures, and maps each to the function it suits.
The property comparison
| Property | ABS | PP | POM |
|---|---|---|---|
| Impact resistance | Good, tough at room temperature | Good, stays tough at low temperature | Moderate, more notch sensitive |
| Stiffness | High | Moderate | High |
| Chemical resistance | Moderate, attacked by some solvents | Good, resists most aqueous and many solvents | Excellent |
| Heat resistance | Good to around 90 C | Good to around 100 C, autoclavable grades higher | Good to around 100 C |
| Surface finish | Excellent, gloss or texture | Good, softer feel | Excellent, low friction |
| Food contact | Not typically used | Common baseline | Used for sliding parts, not typically food contact |
| Cost | Mid | Low | High |
ABS: the structural default
ABS holds dimension, takes colour well, and moulds with a predictable shrink, which is why it is the default for structural parts: chassis, housings, building bricks and figure bodies. Its weakness is chemical: sunscreen, some cleaning agents and certain fragrance oils attack ABS, so a toy that will be handled with sunscreen on small hands should not be ABS.
PP: the safety and outdoor default
PP is the material of choice where the toy will contact food, mouth or water. It is the only one of the three with a straightforward food-contact clearance, it survives repeated washing, and it stays tough in cold weather where ABS becomes brittle. Its weakness is stiffness: a PP part needs more wall or more ribbing to achieve the rigidity an ABS part gets for free, and it creeps under sustained load, so a PP living hinge needs a designed flex limit.
POM: the mechanism material
POM, sold as Delrin and similar, is the material for parts that slide or rotate: gear teeth, cams, axles, snap-fit hooks that must cycle. It has the lowest friction and the best fatigue resistance of the three, and it holds tolerance across temperature. Its weakness is impact: POM is notch sensitive, so a sharp corner at a stress point becomes a crack origin. It is also the most expensive, which rules it out for anything but the mechanism.
Choosing by function
- Body and structural shell: ABS, unless the part contacts food or sunscreen.
- Food-contact and water-play parts: PP, with a food-contact grade where applicable.
- Gears, axles, cams and hinges: POM, with the corner radii designed to avoid notch sensitivity.
- Wheels: PP for the hub with a TPE tyre, or POM where the wheel is also a gear.
The mixed-material decision
Most production toys are multi-material, and the decision that matters is not which single material but which interfaces are between which materials. A POM axle in a PP hub runs cooler and quieter than POM in ABS, because the thermal expansion matches. Documenting the material pairs on the drawing is what stops a well-meaning substitution years later.
Related reading
Our STEM gear kit programme uses ABS gears with POM axles for exactly this reason, and the material guides cover the silicone and TPE side for soft parts.
Related product categories
The materials and part types discussed above are grouped in our sourcing directory:
