LyondellBasell Icorene 3560 G BUE 5747 Polyethylene, Linear Low Density is a formulated linear low density polyethylene grade in which the base resin portion is identified by the Icorene 3560 G designation and the suffix BUE 5747 denotes a blue, ultraviolet-stabilized additive package. The base polymer is a linear low density polyethylene, placing it within the density band defined by ISO 1872-1:2018 for LLDPE materials. The product is supplied in a dry-powder or granular form suitable for rotational molding operations, although the final processing recommendation must be confirmed against the manufacturer’s technical datasheet. Lot-specific melt mass-flow rate, density, additive content, and weathering performance are documented in the certificate of analysis. The following technical description places the grade within established polyethylene property envelopes and distinguishes it from natural LLDPE, branched LDPE, and HDPE alternatives.

For compliance assessment, the base polyolefin chemistry falls within the olefin polymer group referenced by FDA 21 CFR 177.1520 and EU Regulation 10/2011 when the supplier lists the specific grade for food contact. The blue pigment and UV stabilizer system require a separate conformity statement. REACH Candidate List screening and RoHS Directive 2011/65/EU compliance for heavy metals and phthalates should be verified through the supplier’s product declaration before specification in electrical or electronic equipment applications.

Designation Decode and Supply Form

The numeric suffix 3560 in the Icorene designation is conventionally read as a density and melt-flow indicator within LyondellBasell’s linear polyethylene naming system. For this grade, the sequence is consistent with a nominal density of 0.935 g/cm³ and a nominal melt mass-flow rate of 6.0 g/10 min determined at 190°C under 2.16 kg load in accordance with ISO 1133-1:2022 or ASTM D1238-23. The letter G identifies a granular or ground feedstock. This physical form allows direct charging to rotational molding tools without high-shear compounding and is typically associated with biaxial molding processes. The trailing code BUE 5747 is a formulated color and stabilization package. It denotes blue pigmentation combined with a hindered amine light stabilizer or UV absorber system; the exact additive chemistry is specified in the manufacturer’s formula disclosure and is not part of the base resin designation. The practical difference from natural Icorene 3560 G is that BUE 5747 carries the weathering-resistance and color-additive loading needed for outdoor service, whereas the natural grade would require downstream dry-blending with a separate color and UV masterbatch.

How Does the BUE 5747 Package Alter Long-Term Weathering Behavior?

Polyethylene exposed to solar ultraviolet radiation undergoes photo-oxidation by free-radical chain scission and subsequent carbonyl formation. The resulting failure mode is a progressive loss of tensile elongation, surface microcracking, and eventual embrittlement. In a blue UV-stabilized formulation such as BUE 5747, the blue pigment reduces transmitted radiation, while hindered amine stabilizers interrupt the radical propagation cycle. Weathering resistance is verified against accelerated laboratory protocols. Typical designations include ASTM D2565-21, ISO 4892-2:2013, and ASTM D4329-21. The acceptance criterion is normally expressed as a minimum retained tensile elongation after a defined radiant exposure or as a maximum ΔE color shift. Published data for this specific configuration is limited outside the manufacturer’s technical data sheet; therefore, outdoor service life should be requested as a lot-specific accelerated weathering report rather than inferred from resin density alone. The stabilizer package also affects processing economics. Repeated grinding of rejected parts and incorporation of high-regrind fractions progressively consumes the stabilizing system and can reduce the ultraviolet protection of the final molded article.

On carousel and shuttle rotational molding machines, the processing behavior of Icorene 3560 G BUE 5747 is governed by particle size distribution, oven air temperature, mold rotation ratio, and cooling rate. A typical LLDPE rotational molding powder is specified with a maximum of 15% retained on 35 mesh and controlled fines content measured by ASTM D1921. Excessive fines can agglomerate in feed hoppers and create pin holes at the inner mold surface. Coarse fractions may require longer oven residence times to fully sinter and eliminate porosity. In production-scale operation on multi-arm carousels, oven set points for similar density LLDPE powders are commonly held between 250°C and 300°C, with peak internal air temperature usually reaching 190°C to 220°C. Operators monitor the internal air temperature with a thermocouple inserted through the mold vent. Failure to reach the required peak internal air temperature leaves partially fused polymer and reduces impact strength. Excessive peak internal air temperature consumes antioxidant reserves and can shift the blue color. Mold release, wall thickness uniformity, and part porosity are also sensitive to arm ratio; machines operating at 3:1 to 5:1 rotational ratios are common for closed tanks and irregular geometries. Although LLDPE powders are not hygroscopic, bags stored outdoors or opened in high-humidity environments can carry surface moisture that vaporizes during heating and contributes to porosity. If condensation is visible or storage relative humidity exceeds 60%, pre-drying at 60°C for 1–2 h is commonly applied before charging.

If Rotational Molding Conditions Drift Near the Upper Temperature Limit

Thermal degradation in linear low density polyethylene becomes autocatalytic after the polymer stabilizer package is depleted. In rotational molding, degradation is driven by long oven residence times, high oven set points, and oxygen ingress through the mold vent. The visible consequences in a blue grade are a shift toward green or yellow, loss of gloss, surface pitting, and a sharp reduction in dart impact. Differential scanning calorimetry per ISO 11357-3:2018 or ASTM D3418-21 can quantify the crystalline melting peak. For a nominal 0.935 g/cm³ LLDPE, the main melting endotherm typically falls between 123°C and 130°C, but the presence of a melting endotherm does not by itself indicate retained mechanical properties. Oxidative induction time testing according to ISO 11357-6:2018 or ASTM D3895-19 provides a more direct indication of residual stabilizer activity. When the grade is processed repeatedly or held at melt temperatures above 240°C for extended periods, the oxidative induction time declines and the weathering resistance of the BUE 5747 formulation is correspondingly reduced. The upper processing boundary should therefore be established from the lowest temperature that produces complete sintering and bubble removal, not from the maximum oven temperature listed on general polyolefin processing guides.

Rheological and Mechanical Property Bands

Grade-specific property values are issued with each lot and should be used for design calculations. The following table summarizes the general property band for a nominal 0.935 g/cm³ LLDPE rotational molding grade. The values are class-typical and do not replace the certificate of analysis for a specific production lot.

Because LLDPE is a semicrystalline polyolefin, mechanical properties are strongly influenced by cooling rate. Slow cooling inside a rotational mold thickens the crystalline lamellae, raises flexural modulus slightly, and reduces impact strength. Rapid cooling by air or water mist produces smaller spherulites and improves low-temperature impact behavior. The property envelope is therefore not solely a function of melt index and density; it also depends on wall thickness, mold material, and post-mold cooling protocol.

In comparison with branched low density polyethylene, the linear backbone of Icorene 3560 G BUE 5747 provides higher tensile strength and puncture resistance at equivalent melt index, but the sharper melting curve requires tighter control of peak internal air temperature. In comparison with high density polyethylene, the lower density and higher comonomer content of this LLDPE grade reduce flexural modulus and heat deflection temperature while increasing environmental stress crack resistance. In comparison with a metallocene LLDPE rotational molding grade of similar density, a conventional linear low density polyethylene of this type tends to exhibit broader molecular weight distribution, improving powder flow and processing robustness, although dart impact and low-temperature toughness may be somewhat lower. The following table summarizes design-relevant differences among polyethylene subfamilies.

The combination of blue color and UV stabilization makes Icorene 3560 G BUE 5747 suited to outdoor tanks, agricultural liquid storage, marine buoys, and non-pressurized chemical containers where prolonged sunlight exposure is expected. The grade should not be specified for continuous exposure to strong oxidizing acids, aromatic hydrocarbons, or chlorinated solvents at elevated temperatures because these media swell or attack polyethylene. Primary load-bearing design should use a safety factor appropriate for thermoplastic creep, and mechanical fastening should account for the lower modulus of LLDPE relative to HDPE. Within the Icorene 3560 G series, the BUE 5747 variant differs from natural and black UV-stabilized grades principally in colorant type, opacity, and stabilizer formulation. The blue pigment system absorbs visible and ultraviolet radiation; it can reduce light transmission through thin tank walls but may also raise the surface temperature of colored parts in direct sunlight. The blue variant should be specified only when its aesthetic and light-blocking characteristics are required; otherwise, a natural grade with a separate masterbatch provides greater flexibility in color and additive optimization.