Reference Formulas used for Extrusion-Foamed PVC Sheet/Plasticizer DOP dosage

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 Plasticizer (DOP)
Keywords: Plasticizer DOP, PVC Foam, Supercritical CO₂ Foaming, Cellular Morphology, Mechanical Properties

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2. Key Insights with Plasticizer DOP

2.1. Plasticizer 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.