At cast stretch film lines running above 450 m/min, ATTANE 4601 is let down into LLDPE-rich core layers to shift the strain-hardening onset and reduce pre-stretch breakage. The resin is an ethylene-1-octene copolymer with a typical density of 0.912 g/cm³ and a melt index of 3.3 g/10 min under ISO 1133-1:2022 at 190 °C/2.16 kg. Formulation addition ratios in monolayer and 3-layer A/B/A cast film commonly place 20 wt% to 40 wt% ATTANE 4601 in the core layer, while the skin layers retain linear low-density polyethylene with a melt index of 2.0 g/10 min to 4.0 g/10 min to preserve roll release and machinability; edge trim closed-loop recycling is typically capped at 25 wt% of total throughput because lower bulk density trim can generate screw feed surging on single-screw extruders. Compliance is assessed under FDA 21 CFR 177.1520, Regulation (EU) No 10/2011, and REACH SVHC restrictions; finished film is tested under ASTM D882 for tensile properties, ASTM D1922 for Elmendorf tear, ASTM D1709 for dart impact, and ASTM D5748 for puncture propagation resistance. Downstream production uses a cast film line with a 32:1 to 40:1 L/D single-screw extruder, barrel profile from 190 °C to 240 °C, feedblock or multi-manifold die gap of 0.5 mm to 1.0 mm, air-knife or vacuum box pinning, and chill roll temperature maintained between 15 °C and 25 °C; the low crystallinity requires sufficient chill roll contact time to prevent blocking, but roll temperatures below 12 °C may cause condensation defects. Terminal finished product types include machine stretch film in widths from 500 mm to 1,500 mm, hand stretch film, and pre-stretched film for pallet unitization.

What Limits Dart Impact Retention in Frozen Food Blown Film at 0.912 g/cm³ Density?

Frozen food blown film formulations incorporating ATTANE 4601 are typically run on monolayer or 3-layer blown-film lines with die diameters between 200 mm and 500 mm, a die gap of 1.5 mm to 2.5 mm, and an internal bubble cooling cage where available. The addition ratio is normally 15 wt% to 35 wt% of the total polyolefin fraction, blended with LLDPE or LDPE to maintain low-temperature dart impact and heat-seal strength after storage at -25 °C to -40 °C. Industry compliance for direct food contact requires FDA 21 CFR 177.1520 and Regulation (EU) No 10/2011 for migration into frozen and refrigerated food simulants; mechanical verification follows ASTM D1709 for dart impact, ASTM D1922 for Elmendorf tear, ASTM D882 for tensile properties, and ASTM F88 for seal strength. Downstream production employs a grooved-feed or smooth-bore single-screw extruder with 24:1 to 30:1 L/D, barrel temperatures of 170 °C to 210 °C, die head temperature of 200 °C to 220 °C, blow-up ratio from 2.0:1 to 3.0:1, and frost line height adjusted between 400 mm and 800 mm above the die; bubble stability limitations become acute at draw-down ratios above 5:1, where the balance between melt strength and film gauge uniformity must be controlled by dual-lip air ring velocity rather than by raising melt temperature. Terminal finished product types include frozen vegetable bags, meat and poultry overwrap, ice cream liners, and seafood packaging films.

When ATTANE 4601 is assigned to the sealant skin of a high-barrier laminate, the resin is typically coextruded at 60 wt% to 100 wt% in that skin layer, while the adjacent tie and barrier layers remain EVOH- or PA-based. The low seal initiation temperature of the 1-octene copolymer permits sealant layer thicknesses of 8 µm to 25 µm, reducing total polymer consumption in stand-up pouch structures without sacrificing hot-tack performance. Compliance is governed by FDA 21 CFR 177.1520 and Regulation (EU) No 10/2011 for direct food contact, with sealant verification under ASTM F1921 for hot-tack strength, ASTM F88 for seal strength, and ASTM D1894 for coefficient of friction. Downstream production uses a 5-layer blown or cast coextrusion line with separate extruders for skin, tie, and barrier layers; the ATTANE 4601 skin extruder is run with a barrel profile of 180 °C to 220 °C and a metering zone held below 230 °C, while the die gap is set between 0.8 mm and 1.5 mm for blown film and 0.5 mm to 0.8 mm for cast film. Direct contact between ATTANE 4601 and EVOH without the tie layer results in interfacial delamination at seal temperatures above 140 °C. Terminal finished product types include stand-up pouches, zipper pouches, lidding film, and flow-wrap packages for dry and frozen foods.

Heavy-Duty Sack and Industrial Liner Extrusion Window

Heavy-duty sack and industrial liner film based on ATTANE 4601 blends is processed on high-output blown-film lines requiring barrel temperatures across feed, compression, and metering zones of 160 °C, 180 °C, and 210 °C respectively, with a die zone held at 215 °C to 225 °C. The resin is incorporated at 15 wt% to 30 wt% into LLDPE/LDPE compound formulations, where it improves tear propagation resistance and puncture resistance needed for filled sack drop cycles; extruder L/D ratios of 30:1 are typical, and die diameters from 250 mm to 400 mm operate with a blow-up ratio of 2.5:1 to 3.5:1 and a film thickness range of 100 µm to 250 µm. Industry compliance for non-food industrial packaging is driven by REACH SVHC declarations and, where applicable, UN Model Regulations 6.1/6.5 for dangerous goods packaging; mechanical testing includes ASTM D1709 for dart impact, ASTM D1922 for Elmendorf tear, ASTM D882 for tensile properties, and ASTM D5748 for puncture. Downstream production frequently employs screen packs of 100/150 mesh to reduce gel-related defects from post-consumer LLDPE regrind, and edge trim recovery is limited to 20 wt% when the trim contains printed or adhesive-contaminated film. Terminal finished product types include heavy-duty shipping sacks, FIBC liners, chemical drum liners, and construction protective film.

When Pre-Stretch Ratio Exceeds 150% in Stretch Hood Film Production

Because the 0.912 g/cm³ density of ATTANE 4601 lowers crystallinity and shifts cling additive migration, stretch hood lines running above 150% pre-stretch must maintain encoder roll speed differentials between the primary and secondary nips within ±3% to avoid localized yielding. The addition ratio in stretch hood film typically ranges from 30 wt% to 60 wt% in the core and cling-skin layers, with the remaining fraction composed of LLDPE and low-cling surface layers designed to prevent upstream blocking during unwind. Regulatory compliance is based on REACH SVHC content and, for secondary packaging used in food distribution environments, Regulation (EU) No 10/2011 where incidental food contact is possible; physical testing follows ASTM D882 for tensile elongation at break, ASTM D1922 for tear, ASTM D5748 for puncture, and ASTM D4649 for stretch force and unwind force. Production uses a multi-layer blown-film line with 30:1 L/D barrier screws, die gap 2.0 mm to 2.8 mm, blow-up ratio 3.0:1 to 4.0:1, and frost line height 600 mm to 1,000 mm; the higher blow-up ratio imposes transverse orientation, and the 1-octene branch spacing resists dart impact loss at low temperatures in the pallet wrapping cycle. Terminal finished product types include stretch hood film for pallet unitization, top-sheet film, and high-retention pallet wrap used on automated stretch hood machines.

The Cling Retention Window for a 1-Octene VLDPE Matrix Narrows Above 240 °C

In agricultural silage wrap extrusion, ATTANE 4601 is let down at 20 wt% to 40 wt% into an LLDPE-rich cast film matrix to retain cling additive migration and puncture resistance during round bale wrapping; the extruder profile must remain below 240 °C to avoid oxidative gel formation from long-chain branching. Industry compliance for agricultural film does not require food-contact clearance unless the film is later used for silage that enters animal feed, but REACH SVHC verification and absence of lead, cadmium, mercury, and hexavalent chromium under RoHS Directive 2011/65/EU are routinely declared. Mechanical verification follows ASTM D882 for tensile properties, ASTM D1922 for Elmendorf tear, ASTM D5748 for puncture propagation resistance, and ASTM D2732 for unrestrained linear thermal shrinkage. Downstream production uses a cast film line with a 32:1 L/D single-screw extruder, feed throat temperature 40 °C to 60 °C, barrel profile 190 °C to 230 °C, die gap 0.5 mm to 1.0 mm, and chill roll temperature 15 °C to 25 °C; the film is usually produced in 25 µm to 40 µm thickness and slit to 500 mm to 750 mm roll widths for round bale wrappers. Published data for this specific configuration is limited beyond agricultural film technical bulletins; industrial specifications are usually set by bale wrapper OEM tension settings. Terminal finished product types include silage bale wrap, maize silage film, and high-cling agricultural containment wrap.