| Carrier Resin Compatibility | Use a PE-based carrier. LDPE or LLDPE carriers are commonly used for films and flexible products; HDPE carriers are generally more suitable for rigid or higher-stiffness products. | A compatible carrier promotes dispersion, reduces processing instability, and helps prevent surface defects. | Blown film, cast film, bags, sheets, injection-molded parts, extrusion profiles, and pipes. | Uniform distribution without visible agglomerates, die build-up, or significant loss of weld strength. | Check the carrier type, melt flow rate, processing temperature, and compatibility with the base PE resin. |
| Calcium Carbonate Content | Typical commercial grades contain approximately 40%–85% calcium carbonate by mass, depending on the required cost reduction, stiffness, opacity, and processability. | Higher mineral loading can reduce polymer consumption and increase stiffness, but may reduce elongation and impact resistance if overused. | Packaging film, shopping bags, agricultural film, sheets, woven products, and injection-molded items. | Select the lowest loading that achieves the required economics and physical properties. | Review the technical data sheet and confirm mineral content using an agreed laboratory test method, such as ash testing. |
| Recommended Addition Level | Common starting ranges are 5%–15% for film and 10%–30% for rigid or semi-rigid products. Final dosage depends on filler concentration and product requirements. | Excessive addition may cause brittleness, lower tear strength, poor sealing, or unstable extrusion. | Flexible film generally requires lower addition levels than rigid sheets, profiles, or molded parts. | Meet cost and stiffness targets while maintaining tensile strength, elongation, impact resistance, and appearance. | Run a controlled trial at three dosage levels and compare mechanical, optical, and processing results. |
| Melt Flow Rate | Choose a masterbatch MFR that is reasonably close to the base PE resin. Typical commercial values may range from approximately 2 to 25 g/10 min, measured under the specified PE test condition. | A large mismatch can affect extrusion pressure, throughput, layer uniformity, and filler dispersion. | Low-MFR grades for heavier extrusion sections; higher-MFR grades for many film and injection processes. | Stable melt pressure and consistent output at the intended production speed. | Compare masterbatch and base-resin MFR using the same standard and test condition, such as ASTM D1238 or ISO 1133. |
| Moisture Content | A practical target for calcium-carbonate-filled PE masterbatch is commonly no more than approximately 0.2% moisture; lower values may be preferred for sensitive film applications. | Moisture can contribute to bubbles, voids, surface marks, poor appearance, and unstable processing. | Blown film, cast film, thin sheet, and products requiring a smooth surface. | No visible bubbling or pinholing during normal processing. | Measure moisture using a moisture analyzer, Karl Fischer method, or another validated laboratory procedure. |
| Particle Size and Dispersion | Fine, surface-treated calcium carbonate is generally preferred for film and thin-wall products. A typical median particle size for fine grades may be approximately 1–3 micrometres, while coarser grades may be used in less demanding products. | Smaller and well-dispersed particles usually improve surface appearance and reduce the risk of visible specks or weak points. | Thin film, high-opacity film, printed packaging, and smooth extruded sheet. | No visible agglomerates under the agreed visual or microscopic inspection standard. | Review particle-size distribution and evaluate a molded or extruded sample for dispersion uniformity. |
| Surface Treatment | Surface-treated calcium carbonate is often selected for improved compatibility, dispersion, and processing performance. Treatment chemistry should be compatible with the PE carrier and end use. | Treatment can improve filler wetting and reduce processing defects, although it may increase material cost. | High-speed film extrusion, thin products, high-filler formulations, and applications requiring better surface quality. | Improved dispersion and stable output without excessive die deposits. | Request treatment information and compare torque, pressure stability, dispersion, and surface appearance in a production trial. |
| Whiteness and Opacity | Commercial calcium-carbonate masterbatches often provide high whiteness, but actual values depend on mineral purity, particle size, treatment, and pigment composition. | Whiteness and opacity affect visual quality, color matching, print appearance, and the amount of additional white pigment required. | White bags, packaging film, sheets, agricultural products, and household containers. | Consistent color and opacity at the selected addition level and film thickness. | Measure whiteness, L* value, haze, and opacity using agreed instruments and test standards. |
| Mechanical Strength | Adding calcium carbonate generally increases stiffness and may improve modulus, while tensile elongation, tear strength, and impact performance can decrease as filler level rises. | The correct balance depends on whether the product must be flexible, rigid, puncture-resistant, or dimensionally stable. | Flexible packaging, refuse bags, agricultural film, rigid sheets, profiles, and molded components. | Meet the product specification for tensile strength, elongation, tear resistance, impact strength, and flexural modulus. | Test finished products using applicable methods such as ASTM D638, ASTM D882, ASTM D1922, ASTM D1709, or ISO equivalents. |
| Thermal Processing Window | PE filler masterbatch is commonly processed within a PE temperature range, often approximately 160–220°C, depending on the base resin, equipment, residence time, and product design. | Excessive temperature or residence time can cause polymer degradation, discoloration, odor, or unstable output. | Blown film, cast film, extrusion, injection molding, and profile production. | Stable processing without discoloration, burning, excessive pressure, or die build-up. | Confirm the supplier’s recommended temperature range and optimize barrel, die, screw speed, and cooling settings during trials. |
| Surface Appearance | Choose a grade according to the required level of gloss, smoothness, haze, and visible particle control. Higher filler levels generally increase haze and reduce gloss in transparent or translucent films. | Appearance requirements can limit the usable filler level even when mechanical performance remains acceptable. | Retail bags, printed film, clear or translucent packaging, decorative sheets, and consumer products. | Meet the agreed limits for gloss, haze, surface roughness, pinholes, gels, and visible specks. | Use visual inspection and instrument measurements for haze, gloss, roughness, and defect counts. |
| Sealing and Welding Performance | For heat-sealed film, start with a moderate masterbatch dosage and verify the sealing window after filler addition. Calcium carbonate may reduce seal strength or change seal-initiation behavior. | Packaging failure can occur if filler content, particle dispersion, or seal-layer formulation is not controlled. | Shopping bags, sacks, pouches, liners, and multilayer packaging film. | Required seal strength, hot-tack performance, seal-initiation temperature, and leak resistance. | Conduct hot-tack, seal-strength, burst, and leak tests using the customer’s packaging specification. |
| Food and Regulatory Requirements | For food-contact, pharmaceutical, medical, or regulated applications, the complete formulation must comply with the applicable local regulations. Compliance cannot be assumed from the filler type alone. | Carrier resin, additives, pigments, processing aids, heavy metals, and impurities may all affect regulatory status. | Food packaging, consumer packaging, healthcare products, and other regulated goods. | Documented compliance for the intended market and application, with traceable raw materials. | Request a current declaration of compliance, migration information, safety data, and relevant test reports. |
| Cost-in-Use | Evaluate total cost per finished kilogram rather than masterbatch price alone: base-resin replacement, addition level, energy use, scrap rate, throughput, and rejected-product cost should be included. | A lower-priced masterbatch may become more expensive if it requires a higher dosage or causes production defects. | All PE products, especially high-volume film and extrusion operations. | Achieve the lowest total production cost while maintaining the required quality and productivity. | Calculate cost-in-use from trial data at the intended dosage and production speed. |
| Trial and Approval Plan | Use a controlled trial with at least three addition levels, while keeping resin grade, equipment settings, cooling, line speed, and product thickness consistent. | A structured trial separates masterbatch effects from normal process variation. | Recommended for every new formulation, resin change, equipment change, or major dosage adjustment. | A repeatable formulation that meets performance, appearance, compliance, and productivity requirements. | Record process conditions, test results, defect rates, and finished-product performance before approval. |
