LyondellBasell Icorene 3560 BUE 5747 enters primary food packaging as a butene-comonomer linear low density polyethylene selected for coextruded sealant plies in blown-film lines running low-temperature sealing and puncture-loaded distribution cycles. In thin-film structures for frozen vegetables, bakery bread bags, and cereal liners, the sealant ply is typically formulated at 70–85 wt% Icorene 3560 BUE 5747 with 10–25 wt% high-pressure LDPE for bubble stability and 5–10 wt% EVA when a lower seal initiation temperature is demanded by horizontal form-fill-seal machinery; slip/antiblock masterbatch is metered at 1.0–3.5 wt%, and fluoroelastomer processing aid at 0.05–0.15 wt% to suppress melt fracture and die lip build-up on long runs. Direct food-contact compliance is evaluated under FDA 21 CFR 177.1520(c) 3.1 for olefin polymers with density below 0.94 g/cm³, Regulation (EU) 10/2011 Annex I with overall migration limited to 10 mg/dm², and FDA 21 CFR 174.5 for general indirect additive GMP status; converters must additionally verify specific migration behavior where the package is subjected to hot-fill or high-energy sterilization conditions. The downstream production process uses a three-layer or five-layer coextrusion blown-film die with die diameter 150–450 mm, die gap 1.2–2.0 mm, blow-up ratio 2.0–3.0, frost-line height 400–800 mm, melt temperature 180–220 °C, and winding tension maintained below 8 N/mm web width to avoid blocking on 25–60 µm film. Terminal finished product types include 25–60 µm frozen food pouches, produce bags, and form-fill-seal cereal liners with seal initiation below 95 °C when required by high-speed packaging lines.

What Limits Seal Initiation Temperature in High-Speed Horizontal Form-Fill-Seal Lines?

High-speed horizontal form-fill-seal lines running 80–120 cycles/min impose a narrow window between hot-tack strength and seal initiation temperature; extrusion-coated webs based on Icorene 3560 BUE 5747 are blended in the sealant layer at 60–80 wt% with 20–40 wt% LDPE or a low-density metallocene plastomer to reduce neck-in and edge bead while preserving low-temperature sealing. The extrusion coating process employs a 90–120 mm single-screw extruder with L/D 30:1, barrel temperatures from 180 °C to 315 °C, adapter and die held at 315–320 °C, die gap 0.5–0.8 mm, and line speeds of 120–300 m/min; coating weights of 12–30 g/m² are applied to PET, BOPP, or metallized substrates with corona discharge set to 38–42 mN/m. Seal strength is measured under ASTM F88/F88M-21; food-contact status follows FDA 21 CFR 177.1520(c) 3.1 and Regulation (EU) 10/2011; the use of EVA or plastomer in the sealant layer does not alter the polyolefin regulatory status but requires migration testing for specific adjuncts. Process limits are defined by draw resonance at LLDPE contents above 80 wt%, edge bead amplification at coating weights above 30 g/m², and oxidative gel formation at melt temperatures above 320 °C when residence time exceeds 15 min. Finished product types include laminated stand-up pouches, sachet webs for detergent powder, and lidding films for dairy cups with seal initiation at 85–95 °C.

When the Powder Contains Fines Above 15 wt% and Peak Internal Air Temperature Drops Below 205°C

Rotational molding of Icorene 3560 BUE 5747 is process-critical when the ground powder fraction passing 500 µm exceeds 15 wt% fines below 150 µm, because fine-particle packing reduces bulk density, traps air during densification, and produces pinholes in tank walls after cooling; the recommended addition is 100 wt% of the grade pulverized to 35 mesh/500 µm, with 2.0–2.5 wt% carbon black masterbatch for UV stabilization in outdoor service, 0.1–0.5 wt% hindered amine light stabilizer package, and 0.05–0.20 wt% internal mold release to prevent sticking on complex parting lines. Chemical-tank compliance is assessed under ASTM D1998-15 for polyethylene upright storage tanks and EN 13575:2012 for thermoplastic stationary fuel tanks; potable-water variants require Regulation (EU) 10/2011 where applicable, and migration testing under EN 12873-1:2014 may be invoked in procurement specifications.

The production process uses a biaxial rotation ratio of 4:1 on the primary axis, oven set-point 280–300 °C, peak internal air temperature (PIAT) 205–215 °C, and a hold time of 10–20 min after PIAT is reached; forced-air cooling at 20–35 °C is followed by water mist cooling only after internal air temperature falls below 120 °C to limit warpage in flat-sided tanks. The transition from powder to pinhole-free wall fails when PIAT drops below 205 °C because the LLDPE has not reached a low enough melt viscosity for complete particle fusion; conversely, PIAT above 220 °C accelerates oxidative degradation and amber discoloration. Terminal finished product types include 500–10,000 L vertical agricultural chemical storage tanks, 5,000–30,000 L water reservoirs, and portable diesel transport tanks with wall thickness 6–12 mm; published data for this specific Icorene 3560 BUE 5747 configuration is limited where the mold is constructed from fabricated steel without polished seams, so production trials are required for pinhole-critical service.

In flat-die sheet extrusion for geomembrane containment, Icorene 3560 BUE 5747 is processed in calendered or polished-roll sheet lines where the specification demands flexibility at low temperature and stress-crack resistance under landfill leachate. Formulation for a 1.0–3.0 mm geomembrane is 80–100 wt% LLDPE with 0–20 wt% HDPE for stiffness adjustment, 2.0–3.0 wt% carbon black masterbatch with primary particle size below 30 nm, 0.1–0.3 wt% antioxidant package, and 0.02–0.05 wt% fluoropolymer processing aid. Compliance is documented under GRI GM17 for LLDPE geomembranes, ASTM D6693-04 for tensile properties, and EN 13493:2018 for geosynthetic barriers used in solid waste containment. Process equipment includes a 150–200 mm single-screw extruder with L/D 33:1, flat die width 2200–3600 mm, melt temperature 200–230 °C, chill-stack temperature 60–80 °C, and line speed 2–8 m/min; thickness is scanned continuously with beta gauges and held to ±5%. Terminal products are landfill basal liners, mining heap-leach pads, and brine pond liners in widths up to 7.5 m.

Closure Wall Thickness, Gate Freeze Time, and Core-Back Venting in Multi-Cavity Tooling

In multi-cavity closure tooling, Icorene 3560 BUE 5747 is optimized by controlling gate freeze time rather than packing pressure alone; the melt is processed at 180–230 °C with mold temperature 15–30 °C, injection pressure 80–120 MPa, holding pressure 40–60 MPa, and screw back pressure 0.5–1.0 MPa in a L/D 22:1 general-purpose screw. Formulation is either 100 wt% Icorene 3560 BUE 5747 or 80 wt% LLDPE plus 20 wt% HDPE to raise top-load stiffness; color masterbatch is dosed at 1.0–2.0 wt%, slip/antistat concentrate at 0.5–1.5 wt% to improve denesting, and nucleating agents are excluded unless dimensional tolerances below 0.05 mm are required. Food-contact closures are tested under FDA 21 CFR 177.1520(c), Regulation (EU) 10/2011, and dimensional stability under ISO 294-1:2021. Multi-cavity tooling with 8–64 cavities exhibits ovality on thin-wall lids when the gate diameter is below 1.0 mm and the wall thickness falls below 0.7 mm; gate diameter 1.0–2.5 mm and cold runner sizing of 4–6 mm are typical. Terminal finished product types include tamper-evident pail lids, beverage over-caps, and thin-wall storage container lids with cycle times 25–45 s.

For cable jacketing trials with this butene LLDPE grade, pressure-controlled melt delivery and preheated conductors become process-critical because low melt strength can cause eccentricity during high-speed extrusion. Formulation for low-voltage jacketing is 100 wt% Icorene 3560 BUE 5747 or a blend with 10–20 wt% LDPE/EVA for flexibility, carbon black masterbatch at 2.5±0.5 wt%, antioxidant package at 0.2–0.4 wt%, and zinc stearate at 0.1–0.3 wt% as acid scavenger. Compliance is referenced to IEC 60502-1:2021 for extruded insulation and sheaths, ASTM D1248 Type I Class C for PE jacketing, and REACH Article 33 communication when masterbatch additives contain SVHC substances above 0.1 wt%. Extrusion uses a 60–90 mm single-screw extruder with L/D 24:1–30:1, melt temperature 170–210 °C, crosshead pressure 15–30 MPa, conductor preheat 80–120 °C, line speed 50–250 m/min, and water trough temperature 20–40 °C. Terminal finished product types are low-voltage instrumentation cable sheaths and fiber-optic duct jackets with wall thickness 0.8–2.5 mm.