LyondellBasell Icorene 3560 GRN 6102 is classified as a linear low density polyethylene compound based on the 3560-series platform. The grade designation includes a green precolored formulation identified by code 6102 and is positioned for rotational molding of hollow parts. The 3560 series is controlled around a nominal density of 0.935 g/cm³ when tested according to ISO 1183-1:2019 and a melt flow rate of approximately 6.0 g/10 min when measured under ISO 1133-1:2022 at 190 °C with a 2.16 kg load. These values place the product in the medium-density LLDPE class, in which short-chain branching reduces crystallinity and increases environmental stress-crack resistance relative to HDPE. The green pigment package can influence weathering resistance, thermal stability, and food-contact status; those properties must be verified for the specific 6102 formulation.

Resin Identity and Published Property Ranges

Property data for the 3560-series LLDPE rotomolding platform are documented in manufacturer technical literature and lot-specific certificates of analysis. The table lists representative control ranges for a conventional 0.935 g/cm³ LLDPE of this melt flow class; the green 6102 pigment may shift some values, so release data for the exact formulation should be requested.

In powder form, incoming inspection should include particle size distribution and dry flow because rotomolding does not use a melt screw to homogenize. A median particle size of 250–400 µm is common for LLDPE rotational molding powders. Fines below 75 µm should remain below 5 wt%; higher fines fractions can cause bridging in hoppers, irregular mold fill, and dust accumulation on heating equipment. Bulk density near 0.35–0.40 g/cm³ is expected. If the powder is stored in an unheated warehouse and moved into a warm molding hall, condensation on cold powder can create surface porosity; sealed containers should be conditioned to ambient temperature before opening.

Powder Flow and Particle-Size Specification Are Not Cosmetic

Because rotational molding begins with dry powder, the particle size distribution controls how the material packs and densifies against the mold wall. The 3560-series LLDPE should be characterized for bulk density, dry flow through a standard funnel, and screen analysis. A target median particle diameter of 250–400 µm is common. The fraction retained above 600 µm should be minimal, because coarse particles can remain unmelted at the inner surface and produce orange-peel texture. The fraction below 75 µm should be limited to <5 wt%, because fines can create dust, reduce bulk density, and cause bridging in feed hoppers. On production-scale carousel machines, hopper discharge problems often appear as shot-weight variation above ±3%. If electrostatic charge develops, antistatic treatment or humidity control in the storage area may be required.

Quality control of precolored powder includes checking lot-to-lot pigment dispersion. Poor dispersion in the 6102 green concentrate can produce streaking in the molded part even when the base resin is within specification. A rotational molding trial with a flat plaque mold and visual inspection under standard lighting can be used; color difference should be measured in CIELAB coordinates and agreed between supplier and molder. Because pigments can nucleate or destabilize polyethylene during long heating cycles, the thermal stability of each lot should be assessed by melt flow rate retention after multiple heat histories or by oxidative induction time under ISO 11357-6:2018.

What Processing Boundaries Govern Rotational Molding with the 3560-Series LLDPE?

Rotational molding is performed on independent-arm carousel machines, shuttle machines, closed-oven rock-and-roll equipment, or open-flame rock-and-roll equipment. The primary control variable is peak internal air temperature, which reflects heat transfer through the mold wall and the progress of powder densification. For a 0.935 g/cm³ LLDPE with a melt flow rate of 6.0 g/10 min, the heating phase is generally terminated at an internal air temperature of 180–210 °C. Steel molds typically require a mold surface temperature of 220–240 °C; aluminum alloy tools can run 20–30 °C lower because of higher thermal conductivity.

Oven air setpoints between 260 °C and 320 °C are used in production-scale rotomolding. At 285 °C oven air and a 6 mm nominal wall in a closed steel tool, heating times of 18–24 min are reported for this LLDPE melt flow class; published data for the exact Icorene 3560 GRN 6102 configuration is limited, so mold-specific thermal trials are required. Higher oven air temperatures shorten cycle time but increase the risk of oxidative degradation at the inner air surface. For precolored green material, the maximum allowable peak internal air temperature may shift by 5–10 °C compared with natural material because organic pigments can influence thermal stability. The time above 200 °C for a 6 mm wall should be limited to approximately 10–12 min until supported by oven trials.

The 6.0 g/10 min melt flow lowers melt viscosity relative to lower-melt-flow rotomolding LLDPE grades. This improves consolidation in narrow ribs, inserts, and thin-wall sections, but it reduces the melt strength that maintains uniform thickness on vertical walls. Rotation ratio and mold indexing must be adjusted for each geometry. Cube-like molds commonly begin with a primary-to-secondary rotation ratio of 4:1 or 5:1, but the correct setting is validated by wall-thickness mapping. Cooling is staged to control warpage: forced-air cooling for 10–20 min, followed by water mist only if necessary. Excessive water quenching can freeze in residual stress and produce voids in thick sections. Demolding at 70–80 °C is common for LLDPE parts to reduce post-mold distortion.

Production-scale defects observed with LLDPE rotomolding powders of this class include pinholes from entrapped air, surface porosity from moisture or excessive oven temperature, and warpage from nonuniform cooling. If surface moisture is suspected, drying at 70–80 °C for 2–4 h in dehumidified-air equipment is appropriate. Clean regrind can be used, but particle size distribution must be controlled; excessive regrind fines can reproduce the same flow and porosity defects as virgin fines.

If a Six-Gram Melt Flow Rate Replaces a Two-Gram LLDPE in Thin-Wall Tools

In plants that previously processed a 2.0 g/10 min LLDPE of identical density, the move to the 6.0 g/10 min 3560 platform changes cycle time and mechanical balance. The lower melt viscosity permits void-free densification at lower internal air temperature or shorter heating time. In thin-wall parts with coring or complex parting lines, the heating segment can often be shortened by 10–20%; for a 3 mm wall, the oven setpoint may be reduced by 10–20 °C or the heating time shortened by 2–5 min relative to a 2.0 g/10 min grade. At the same time, lower average molecular weight reduces the population of tie-chain segments linking crystalline lamellae, so low-temperature impact and puncture resistance are expected to be lower than those of a lower-melt-flow LLDPE of the same density. The reduction is geometry- and cooling-rate-dependent; published product-specific data for this green 6102 formulation is limited. The processing window is narrower for large flat panels than for rotationally symmetric shapes because of the lower melt strength.

To Compare HDPE, Conventional LLDPE, and Metallocene LLDPE for Rotomolded Service

The 3560-series material differs from high-density polyethylene rotomolding grades in density, stiffness, and slow-crack-growth response. Rotomolding HDPE with density 0.945–0.955 g/cm³ typically provides higher flexural modulus and heat deflection temperature but lower environmental stress-crack resistance and lower impact toughness than an LLDPE at 0.935 g/cm³. The LLDPE may be selected instead of HDPE when resistance to slow crack growth under multiaxial stress is required. Compared with metallocene-catalyzed LLDPE, a conventional LLDPE of this density and melt flow class often has lower dart impact and puncture energy at equal thickness but broader processing latitude in older rotomolding machines because of its molecular weight distribution and lower melt elasticity under slow rotational flow. The 3560 grade should not be treated as a drop-in replacement for metallocene LLDPE in demanding low-temperature impact applications without comparative falling-weight testing under ISO 6603-2:2023.

This comparison is directional; actual performance depends on part geometry, cooling rate, and colorant package. A hard switch between material classes should be supported by falling-weight tests, wall-thickness mapping, and oven cycle logs from the target machine.

Unlike peroxide-crosslinked HDPE rotomolding grades, Icorene 3560 remains a thermoplastic. This permits regrind reuse and post-molding repair by welding, but it limits load-bearing service at elevated temperatures. The Vicat softening temperature of 115–120 °C is not a continuous service temperature; load-bearing parts should be restricted to intermittent exposure near 60–70 °C unless creep testing demonstrates otherwise. For fluid-contact service, the base resin may comply with FDA 21 CFR 177.1520 or Regulation (EU) No 10/2011, but the final precolored formulation must be tested because pigments and stabilizers can alter migration behavior.

Typical applications for a green 3560-series LLDPE are rotationally molded agricultural chemical tanks, stationary water storage containers, outdoor playground components, turf equipment, and small marine buoys. UV stability of the 6102 green formulation should be verified by accelerated weathering under ISO 4892-2:2013 or ASTM G155-21. For chemical containers, immersion testing in the intended chemical at maximum service temperature is required; generic LLDPE data do not establish compatibility with concentrated pesticides, bleach, aromatic hydrocarbons, or chlorinated solvents. Strong oxidizing acids at elevated temperature can degrade the polymer, and stress-crack resistance after chemical contact should be evaluated. Rotational molding trials should include wall-thickness mapping, low-temperature impact testing, and sustained pressure or vacuum testing for closed tanks.