PU Resin
Flexible Casting Resin (PP-Like)
Flexible PU Resin
Semi-flexible casting resin mimicking Polypropylene (PP), offering a balance of impact resistance and flexibility.
| Compatible Technologies | Vacuum Casting |
| Tensile Strength | 42 MPa |
| Heat Deflection Temperature (HDT) | 85°C |
| Hardness | 75 (Shore D) |
| Available Colors | Black |
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Why Choose Flexible Casting Resin (PP-Like)?
Flexible Casting Resin (PP-Like) delivers the high impact resistance and flexibility of industrial-grade Polypropylene (PP) using Vacuum Casting technology. It is excellent for snap-fits, clips, and especially “living hinge” applications where parts must flex without breaking. Available in semi-transparent or colored finishes, this material is the ideal solution for achieving injection molding quality in low-volume production runs.
Advantages
Living Hinges: Performs perfectly in integral hinge designs that need to withstand repeated flexing without fatigue.
High Impact Resistance: More durable than ABS against drops and shocks; it flexes rather than shatters.
Chemical Resistance: Offers Polypropylene-like resistance to moisture, solvents, and various chemicals.
Lightweight: Low density makes it advantageous for automotive and lightweight functional parts.
Limitations
Post-Processing: Like real PP, it has low surface energy, making it harder to paint or bond compared to ABS-like resins.
Rigidity: Not suitable for structural parts that require high stiffness and zero flex.
Tolerances: Due to its flexibility, holding extremely tight tolerances (under ±0.1mm) is more challenging than with rigid resins.
Mechanical Properties
Metric Measurements
Elastic Modulus
1.6 GPa
Elongation at Break
25 %
Density
1.13 g/cm³
Nylon PA12 Material FAQ
When should I use PP-Like Flexible Casting Resin?
You should choose PP-Like Flexible Casting Resin when your part requires flexibility without breaking, specifically for snap-fit assemblies, clips, and impact-absorbing housings.
Is PP-Like Flexible Resin suitable for “living hinge” applications?
Yes, this is the primary advantage of this material. PP-Like Flexible Resin demonstrates high fatigue resistance, making it perfect for single-piece hinge designs that need to bend repeatedly without tearing.
Can parts made with PP-Like Flexible Resin be painted?
PP-Like Flexible Resin has low surface energy, similar to actual Polypropylene. While painting is difficult, we can achieve the desired look by adding pigments directly into the liquid PP-Like Resin before casting.
How is the impact strength of PP-Like Flexible Resin?
PP-Like Flexible Casting Resin has very high impact strength. Unlike brittle plastics, it absorbs impact energy by flexing and tends to return to its original shape rather than cracking.
Do PP-Like Flexible Casting parts offer water tightness?
Yes. Parts manufactured with PP-Like Flexible Resin offer excellent chemical resistance and can provide watertight seals when designed correctly (e.g., bottle caps or containers).
Is this material the same as Rubber-like casting resin?
No. PP-Like Flexible Resin is not soft like rubber; it is a semi-rigid plastic. It holds its shape under gravity but flexes under load. Rubber-like resins are elastomeric and much softer.
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