This article highlights actionable insights for manufacturers seeking to refine PVC foam formulations while emphasizing plasticizer DOP as a pivotal tool for performance optimization.
1. Reference Formula/ Plasticizer DOP dosage
| Material | PHR[Parts by weight per hundred parts of resin] |
|---|---|
| PVC | 100 |
| Organotin stabilizer | 2 |
| PE wax | 1 |
| Ester lubricant | 3 |
| Stearic acid | 0.3 |
| CaCO₃ | 10 |
| ACR | 6 |
| Plasticizer DOP | 2 |
Title: Optimizing Extruded PVC Foam Performance: The Critical Role of DOP
Keywords: Plasticizer DOP, PVC Foam, Supercritical CO₂ Foaming, Cellular Morphology, Mechanical Properties
2. Key Insights with Plasticizer DOP
2.1. DOP Enhances Melt Flow and Processability
- Rheological Benefits: Adding DOP reduced both melting torque and equilibrium torque by up to 30% (at 2 phr), improving PVC’s flow characteristics and lowering extrusion pressure.
- Optimal Dosage: 2 phr DOP achieved the best balance between melt elasticity (for cell nucleation) and melt strength (to prevent collapse).
2.2Microstructure Optimization
- SEM Analysis:
- 2 phr DOP: Uniform, fine cells (optimal morphology).
- Density Control: 2 phr DOP yielded the lowest density (~0.5 g/cm³) due to uniform cell growth.
2.3 Mechanical Performance Trends
- Tensile Strength: Decreased by 1.9% (0–2 phr) and 16.9% (2–4 phr) as DOP weakened intermolecular bonds.
- Elongation at Break: Peaked at 2 phr (improved flexibility) but dropped with higher DOP (structural instability).
- Flexural & Impact Strength: Declined consistently with DOP content due to reduced melt strength.
2.4. Practical Guidelines
- Recommended DOP Level: 2 phr balances processability, cell uniformity, and mechanical integrity.
- Avoid Overuse: Excess DOP (>2 phr) risks foam collapse and inferior performance.