Why Does Conductive PP Pass Pellet Testing but Fail After Injection Molding?
This page is designed for buyers and engineers who need to select a conductive plastic compound based on real application validation, not only a single resistance value.
Search Intent / Page Positioning
This page is designed for buyers and engineers who need to select a conductive plastic compound based on real application validation, not only a single resistance value.
DGK-PP DD2-3A Conductive PP and DGK-PP DD4-5A-JC Flame Retardant Conductive PP. Choose the PP grade by molded-part validation, not only by pellet or standard plaque resistance.
1. Background / Problem
Conductive plastics are not selected only by checking whether a material can reach a target resistance value. In production, buyers usually need to balance conductivity, injection molding stability, mechanical strength, surface appearance, cost and long-term reliability.
Passing a pellet or standard plaque test does not automatically mean the final molded part will pass. Wall thickness, gate position, filler orientation, cooling rate, drying and service conditions can all change the conductive network.
2. Technical Difficulty / Why It Happens
Conductive modification changes the original behavior of the base resin. Common technical conflicts include:
- A standard plaque is only a starting point; the gate position and flow length can change the conductive network.
- Very low resistance can reduce impact strength or narrow the process window if filler loading is too high.
- For flame-retardant conductive PP, the flame-retardant system and conductive system must be balanced together.
- Final validation should map resistance at multiple positions on the molded part.
For this reason, DEYU treats conductive plastic selection as an application system: base resin, filler route, resistance target, mechanical balance and final-part validation must be matched together.
3. DEYU Material Direction
DEYU may recommend different DGK material directions according to resistance target, base resin and application environment.
| Grade | Base Resin | Corrected Data Direction | Typical Use |
|---|---|---|---|
| DGK-PP DD2-3A | PP | Conductive 10^2-10^3 ohm | Low-resistance PP parts, shielding-related components |
| DGK-PP DD4-5A-JC | PP | V-0; 10^3-10^5 ohm; black | Flame-retardant conductive PP parts |
| DGK-LDPE DD4-5 | PE | Surface resistance around 10^3-10^5 ohm | Molded ESD parts and conductive PE applications |
| DGK-ABS DD3C | ABS | Graphite conductive ABS, around 10^3-10^4 ohm | Conductive ABS housings and ESD cases |
| DGK-ABS CF15L | ABS | Flexural strength >=138 MPa; surface resistance <=10^4 ohm-cm | Rigid carbon-fiber conductive ABS parts |
| DGK-PA66 CF15L-CF40L | PA66 | 15%-40% carbon fiber customizable | High-strength conductive PA66 structural parts |
| DGK-POM DD4-5ML | POM | Conductive 10^4-10^5 ohm; glossy surface and good toughness | Sliding ESD parts and electronic accessories |
| DGK-TPU DD3-4ML | TPU | Conductive 10^3-10^5 ohm; hardness 85A-95A | Flexible conductive and wear-resistant parts |
| DGK-TPR DD6-9A | TPR | Conductive 10^5-10^6 ohm; hardness 78A +/-2 | Soft ESD parts and sealing strips |
4. Reference Product Data
The values above are corrected from existing DEYU product pages and should replace corrupted or incomplete draft numbers. For a final supply decision, exact values should still be confirmed by DEYU internal testing and customer part validation.
5. Customer Debugging / Validation Scenario
In this validation scenario, a customer compares an original material, a previous trial and a DEYU DGK trial direction. The goal is not only lower resistance, but stable molding, surface quality, mechanical balance and part-level pass rate after internal testing.
6. Validation Data Table
| Item | Original Direction | Previous Trial | DEYU Validation Direction |
|---|---|---|---|
| Plaque resistance | Met target | Met target | Met target |
| Final-part resistance variation | High | Medium to high | Target reduced |
| Molding scrap rate | 7.5% | 6.2% | Target <4.0% |
| Warpage / shrinkage issue | Medium | Medium | Reduced |
| Assembly scrap rate | 3.8% | 3.0% | Target <2.0% |
| Final internal pass rate | 75% | 84% | Target >92% |
This is a validation scenario, not a published customer case.
7. Result Interpretation
The key improvement is not simply lowering resistance. A correct conductive compound must keep a stable conductive network after compounding, drying, molding and final use.
For PP and PE, dispersion and flowability are usually critical. For ABS and PA66, stiffness, warpage and assembly cracking must be checked. For POM, TPU and TPR, wear, elasticity and contact behavior should also be evaluated.
8. Suitable Applications
- ESD trays and conductive liners
- Conductive housings and fixtures
- Carbon-fiber reinforced ABS and PA66 structural parts
- Conductive POM sliding components
- Conductive TPU and TPR flexible parts
- Flame-retardant conductive PP components
9. What Buyers Should Provide
To improve validation efficiency, buyers should provide the base resin, target resistance range, test method, part drawing or sample, wall thickness, processing method, color requirement, impact target, warpage requirement, flame-retardant or wear requirement and application environment.
Conclusion
Conductive plastic selection should be validated by matching resin system, conductive route, resistance target, mechanical balance and actual molded part performance. DEYU can support DGK conductive PP, PE, ABS, PA66, POM, TPU and TPR material directions for small-batch validation and application-based adjustment.
