In masterbatch, the carrier polymer shapes performance as much as pigment or additive. Even with the right shade, a wrong carrier can cause gels, poor dispersion, delamination or mechanical loss — especially visible on PE and PP lines.
Why not mix PE and PP casually?
Polyethylene and polypropylene look related chemically, but crystal structure, melting behavior and compatibility differ. A PP-heavy carrier on a PE film line can hurt melt flow, film uniformity and surface appearance. The reverse can also create unexpected flow and cooling behavior in injection or blow molding.
What we check in practice
- MFI / melt flow: Fit to the processing window
- Melting point and process temperature: Over/under-melt risk
- Pigment dispersion: Effect of carrier viscosity on distribution
- Mechanical outcome: Impact, tensile and surface roughness
- Recycled / mixed scrap: Incompatible matrix risk
Pre-formulation briefing checklist
- What is the base polymer? (LDPE, LLDPE, HDPE, PP homo/copa…)
- What is the product type? (film, bottle, injection, fiber…)
- What dosage and opacity/shade target are expected?
- Any process additives? (UV, slip, antiblock…)
- What is the approval criterion? (visual panel, Delta E, customer lab)
How RH Polimer manages it
We collect polymer matrix and process data first, then propose a carrier-compatible grade and validate on a pilot sample when needed. This reduces scrap and reformulation costs from “right color / wrong carrier”.
Contact us if you need help with carrier selection, custom color or additive combinations.