SABIC LLDPE 6118LE Downstream Application Profiles

SABIC LLDPE 6118LE is a linear low-density polyethylene grade with a melt flow rate of 1.0 g/10 min at 190 °C/2.16 kg determined under ISO 1133-1:2022 and a nominal density of 0.918 g/cm³ measured under ISO 1183-1:2019. The grade is specified for blown film conversion where drawdown, dart impact retention, and seal integrity control downstream yield. The following profiles cover five verified application segments: frozen-food packaging film, agricultural silage and greenhouse covers, adhesive-laminated sealant webs, heavy-duty industrial liners, and e-commerce mailer films. Injection molding, blow molding, rotomolding, and pipe extrusion are outside the specified conversion window for this resin.

When Does Bubble Instability Limit High-Drawdown Frozen-Food Film Output?

In frozen-food film conversion, SABIC LLDPE 6118LE is processed on grooved-feed barrier extruders with screw diameters of 45–75 mm and L/D ratios of 30:1; the melt temperature measured at the adaptor is controlled to 190–205 °C because higher thermal exposure accelerates gel formation and impairs optical homogeneity. Die gaps of 1.8–2.4 mm are retained across the circumference, and the bubble is stabilized in a high-stalk configuration with frost-line height between 6 and 8 die diameters. Blow-up ratio is maintained at 2.0:1–3.0:1, while layflat widths above 1,600 mm require internal bubble cooling to sustain outputs above 0.55 kg/h per cm die circumference. The formulation for frozen vegetable and bakery films uses 70–80 wt% 6118LE and 20–30 wt% high-pressure LDPE to raise melt extensibility; slip masterbatch addition is 0.5–1.5 wt% when film-to-film coefficient of friction must remain below 0.30, and synthetic silica anti-block is dosed at 0.1–0.4 wt% for roll windability. Downstream converting includes surface corona treatment at 38–42 mN/m and center-fold heat sealing at jaw set temperatures of 105–130 °C. Terminal products include frozen vegetable pouches, ice-cube bags, bakery over-wrap, and dry-food liners. Compliance for direct food contact under Regulation (EU) No 10/2011 requires overall migration not exceeding 10 mg/dm², while FDA 21 CFR 177.1520 classifies the olefin polymer by extractable fraction under the intended condition of use. Operational boundaries include avoiding melt temperatures above 250 °C and limiting residence time to less than 15 min at 200 °C; if resin granules are stored above 60% relative humidity, hopper drying at 70 °C for 4 h prevents moisture-generated pinholes. Die-lip buildup is managed by maintaining die temperature uniformity within ±3 °C.

Silage cover formulations based on 6118LE require UV stabilization against long-term solar exposure because the base resin does not contain a sufficient hindered-amine light stabilizer package for multi-year agricultural service. The polymer phase is kept at 90–100 wt% 6118LE, with up to 10 wt% metallocene LLDPE or LDPE for tack adjustment in clamp applications; HALS active dosage is 0.25–0.60 wt% in the finished film, supplied as a 10% UV masterbatch at 2.5–6.0 wt%. White or black pigment masterbatch is incorporated at 6–12 wt% to block transmission below 400 nm, and anti-drip agents are dosed at 0.5–1.0 wt% for greenhouse side sheets. Processing uses low-stalk blown film lines with die gaps of 2.0–2.6 mm, blow-up ratios of 2.5:1–3.5:1, and final thickness between 120 and 200 µm for silage clamp covers. Frost-line height is lowered to 3–5 die diameters to reduce film haze; output rates are limited by bubble cooling capacity because thick gauges above 150 µm retain heat at the nip. Terminal products include silage clamp side sheets, greenhouse anti-drip films, and low-tunnel perforated covers. Compliance for silage films references EN 13207:2018 for elongation retention after weathering and EN 13206:2017 for greenhouse covering films; pesticide contact with sulphur-containing agrochemicals can consume phenolic antioxidants, so end-use exposure trials are required before multi-season warranty claims. Operational boundary: direct contact with chlorinated water or fumigant vapours containing methyl bromide is not recommended; published data for this specific grade under those exposure conditions is limited.

Adhesive-Laminated Sealant Web: Pot Life and Seal Initiation Boundaries

A sealant web produced from 6118LE is deposited as a blown film at 25–40 µm and subsequently adhesive-laminated to PET or BOPP at a solvent-free adhesive coat weight of 2–4 g/m². The polymer fraction of the sealant layer contains 80–95 wt% 6118LE and 5–20 wt% metallocene plastomer to depress seal initiation to 80–95 °C; anti-block of 0.1–0.3 wt% is added only when the film is wound under high-humidity roll storage. The blown film process uses die gaps of 1.6–2.0 mm, BUR of 2.0:1–2.5:1, and melt temperatures of 180–200 °C to limit low-molecular-weight extractables. Lamination curing is conducted at 35–40 °C for 24–48 h, after which the sealant web is slit and pouch-making is performed at 40–60 cycles/min on vertical form-fill-seal lines. Terminal product types include dry-food stand-up pouches, snack pillow pouches, and non-food detergent refill packs where seal integrity under drop tests is specified. Compliance under Regulation (EU) No 10/2011 applies when the adhesive is separated from food by the sealant web; migration testing is carried out on the finished laminate using EN 1186-2 total immersion or cell methods. The operational limit of 6118LE in this structure is its melt flow rate of 1.0 g/10 min: if direct extrusion coating is attempted without a high-MFR LDPE coextrudate, die pressure becomes unstable above 150 m/min line speed and pinholing occurs. Published data for solvent-free lamination pot life with this specific sealant film is limited; adhesive viscosity doubling times should be verified against the adhesive manufacturer’s batch data.

Where drum liners and FIBC inner plies are extruded from 6118LE, the resin is blended with high-density polyethylene to control creep and film stiffness at cargo temperatures above 40 °C. The recommended polyolefin fraction is 60–75 wt% 6118LE and 25–40 wt% HDPE; a fluoroelastomer processing aid at 0–400 ppm is used only after melt fracture occurs at screw speeds exceeding 80 rpm, and carbon black masterbatch is added at 2–4 wt% if UV resistance is needed for outdoor storage. Film extrusion takes place on 65–90 mm grooved-feed lines with die gaps of 2.0–2.4 mm, BUR of 1.8:1–2.5:1, and melt temperatures of 190–210 °C. Frost-line height is fixed at 5–8 die diameters, and internal bubble cooling is used above 120 µm gauge to maintain dart impact targets of ≥ 800 g at 100 µm under ISO 7765-1/ASTM D1709; converter trials report that HDPE addition beyond 40 wt% reduces dart impact rapidly and should be avoided for cold-climate stacking. Terminal products include FIBC inner liners for hygroscopic chemical powders, drum liners for non-oxidizing liquids, and heavy-gauge box liners. Compliance for FIBC packaging under ISO 21898:2004 is package-level, not resin-level; UN dangerous goods certification requires testing of the complete bag and liner. The liner is not suitable for direct contact with strong oxidizing agents above 50 °C or with aromatic hydrocarbon fills above 40 °C; published data for this specific configuration is limited, and fill compatibility tests must be conducted before shipment.

E-commerce Mailer Film Puncture Resistance and Ink Adhesion

The addition of recycled LLDPE to 6118LE in e-commerce mailer film is controlled at 15–30 wt% to retain puncture propagation resistance; the prime 6118LE fraction is 70–85 wt%, and black or coloured masterbatch is dosed at 2–6 wt%. Three-layer coextrusion is used rather than monolayer to place recycled content in the core layer and maintain outer-surface ink adhesion. Die gaps are 1.6–2.0 mm; blow-up ratios are held at 2.0:1–2.8:1; film thickness is 60–100 µm after layflat winding. Corona treatment at 36–40 mN/m is applied to the print face, and flexographic or water-based ink adhesion is tested with tape pull under ISO 2409 or equivalent cross-cut method; delamination is not acceptable beyond 5% of the cut area. Converting includes side-gusset or bottom-seal pouch formation and self-seal adhesive strip application, with seal bar temperatures of 110–135 °C. Terminal products include non-food e-commerce mailers, apparel shipping bags, and protective over-pack for books. Compliance under Directive 94/62/EC requires the sum of lead, cadmium, mercury, and hexavalent chromium not to exceed 100 mg/kg in packaging; REACH candidate list screening is required when post-consumer recyclate is used. Operational limits: batch-to-batch gel counts increase with recycled content above 30 wt%; a melt screen with aperture of 80–120 µm is required upstream of the die. This film is not intended for food contact because post-consumer recyclate is not food-grade, and no statement of food-contact compliance should be made.