Temperature control represents the most immediate technical hurdle. While traditional plastics (PE/PP) enjoy a broad thermal stability range, TPS operates within a narrow window.
Triggers rapid thermal degradation, yellowing, and catastrophic tensile loss.
Essential for managing sensitivities and ensuring full melting without scorching.
Rheological Behavior & Shear Sensitivity
Internal friction can degrade the material before it even reaches the die. Screw speed and die geometry must be optimized.
Viscous Dissipation
High screw speeds cause localized overheating in TPS due to extreme shear sensitivity.
Melt Strength
Pure TPS often lacks the structural integrity for complex film blowing without formulation offsets.
Die Geometry
Refined geometries are mandatory to prevent dimensional deviations and surface fracture.
The Logic of Alloy Technology
Compounding is the industry’s standard solution. By creating "alloys" with biodegradable polyesters like PBAT or PLA, we match traditional PE or PS performance.
- Maleic Anhydride-grafted (MAH-g) Compatibilizers
- Vented Extrusion with High-Vacuum Degassing
- Strategic Moisture Stripping
Hydrolysis Prevention
Moisture management is critical during reactive extrusion. Utilizing a vented extruder is mandatory to prevent hydrolysis that weakens polyester components.
Equipment Adaptation
Low-Shear Screw Design
Replace GP screws with high L/D ratios to prevent mechanical degradation during melt processing.
Desiccant Drying Systems
Standard hot-air is insufficient. Transition to desiccant-based dehumidifying for hygroscopic starch resins.
Gate & Runner Optimization
Enlarge gates to account for flowability differences and minimize internal stress during molding.
Ready to Transition?
Navigating the complexities of Thermoplastic Starch is a manageable process with the right expertise. Let our engineers evaluate your existing production lines.
Free Equipment Compatibility Audit Available
Maintaining Molecular Integrity in Recovery
Regrind Strategy
TPS scrap requires strategic blending with virgin material. Each heat cycle reduces molecular weight, unlike the more stable recovery profile of PE.
Cooling Periods
Cycle times must be adjusted based on crystallization kinetics, ensuring mechanical properties remain consistent in final applications.
Conclusion
By respecting the rheological sensitivities and narrow thermal limits of TPS, processors can successfully leverage their existing infrastructure to produce sustainable, high-performance alternatives to conventional synthetics.
