Melt Flow Rate (MFR) functions as the technical DNA that governs manufacturing viability, serving as the primary indicator of how resin performs under thermal and shear conditions.
Identifying the appropriate grade requires looking far beyond a simple product label. While sustainability defines environmental value, MFR acts as a proxy for molecular weight and rheological behavior.
Technical success starts with matching molecular architecture to equipment capabilities. To understand the foundational chemistry, explore our comprehensive framework: Selecting the Right Polylactic Acid Plastic for Your Application.
"MFR is the critical bridge between chemical formulation and industrial production."
Injection Molding: High Precision vs. Rapid Cycle Times
Precision components and thin-walled parts demand resins with balanced flow to ensure complete cavity filling.
High-MFR (15–40 g/10min) reduces injection pressure, minimizing internal stress and warping.
Lower viscosity enables faster cycles, maintaining dimensional tolerance in intricate connectors.
Optimize Your Production Parameters
Matching the correct MFR to your machinery is the fastest way to improve yield and reduce energy consumption. We provide a wide spectrum of Polylactic Acid Plastic resins, from high-flow injection grades to high-viscosity extrusion formulations.
Are you experiencing inconsistent flow or high scrap rates? Contact our Materials Engineer today for a technical audit of your TDS requirements or to request a quote on a grade matched to your specific mold design.
Extrusion & Thermoforming
Sheet extrusion necessitates high viscosity—the opposite of injection molding. Target: 2 - 8 g/10min
- Melt Strength: High viscosity prevents "sagging" as sheets exit the die.
- Deep-Draw Stability: High entanglement density ensures material stretches without tearing.
Blow Molding & Film Blowing
The most demanding process, requiring stable, pressurized "bubbles" in a molten state.
- Stability Challenge: PLA possesses lower melt elasticity than PE, risking bubble flicker.
- Solution: Use branched molecular structures to enhance the strain-hardening effect.
The Grade Selection Matrix
| Processing Method | Target MFR (190°C/2.16kg) | Critical Secondary Metric | Primary Objective |
|---|---|---|---|
| Injection Molding | 10 – 40 g/10min | Mold Shrinkage Rate | Dimensional Precision |
| Sheet Extrusion | 2 – 7 g/10min | Glass Transition (Tg) | Surface Uniformity |
| Film Blowing | 1 – 5 g/10min | Melt Strength / Elasticity | Bubble Stability |
| 3D Printing (FDM) | 10 – 20 g/10min | Interlayer Adhesion | Clog-free Extrusion |
Even the most precise grade selection can be compromised by poor moisture management. Polylactic Acid Plastic is highly sensitive to hydrolysis; if the resin is not dried to <100 ppm, the MFR will artificially spike during processing due to chain scission. This lead to brittle parts and inconsistent flow.
