ExxonMobil Exceed mLLDPE 1018EA is a metallocene-catalyzed linear low-density polyethylene supplied in pellet form for cast film extrusion and coextrusion. Supplier technical documentation identifies the grade as an ethylene-hexene copolymer. The base resin density is 0.918 g/cm³ when measured by ASTM D1505-18, and the melt index is 1.0 g/10 min when measured by ASTM D1238 (190°C, 2.16 kg). The single-site catalyst architecture produces a narrow molecular weight distribution and a more homogeneous short-chain branch distribution than multi-site Ziegler-Natta LLDPE. The grade designation 1018EA therefore combines a low crystalline density with a moderate melt viscosity suited to cast film lines; it is not a high-melt-strength autoclave or tubular LDPE replacement. In final film form, the resin is positioned for toughness-critical, low-haze, and low-temperature sealing applications where the film is converted by cast film lines rather than by extrusion processes requiring high melt elasticity.

Film-dependent properties such as dart impact, haze, tear, and seal initiation are intentionally not reduced to a single pellet value because they require a defined film thickness, layer structure, quench rate, and draw ratio.

What Structural Feature Differentiates 1018EA from a 0.918/1.0 Ziegler-Natta Butene LLDPE?

The differentiation is not captured by density and melt index alone. A conventional ZN LLDPE with equivalent ASTM D1505 density and ASTM D1238 melt index can contain a broad distribution of molecular weights and an uneven placement of comonomer. In such grades, the low-molecular-weight, high-density fractions crystallize into thick lamellae, increasing film haze and yield stress while reducing dart impact. In 1018EA, the single-site catalyst incorporates the 1-hexene comonomer more uniformly along the chain and across the molecular weight distribution. The narrower short-chain branch distribution suppresses the high-crystallinity, comonomer-poor fraction. Film dart impact measured by ASTM D1709-15a on 25 µm cast film is therefore higher than that of an equivalent melt index and density ZN butene LLDPE, although the exact value is line-dependent because quench rate, draw ratio, and layer distribution control crystallite size and orientation. Haze measured by ASTM D1003-21 is lower for metallocene grades at the same film gauge, and seal initiation temperature measured by ASTM F2029-16 shifts downward. The grade remains linear with negligible long-chain branching; this absence of long-chain branching reduces melt elasticity and shear thinning compared with LDPE, which directly affects die swell and bubble stability.

On cast film lines, the resin is introduced through the main extruder fitted with a barrier screw and an L/D ratio between 24:1 and 30:1. Because 1018EA is linear and has a narrow molecular weight distribution, its shear thinning is less pronounced than that of LDPE under equivalent screw speed. The head pressure at a fixed output is accordingly higher, and the extruder drive load can become the limiting factor before melt temperature does. Melt temperature measured in the adapter is typically maintained between 220 °C and 260 °C for cast film; above 280 °C, oxidative degradation generates gel particles that reduce film appearance and can create holes during orientation. The grade does not require pre-drying for normal indoor storage. Where condensed surface moisture is present from outdoor storage or high relative humidity, hopper drying at 60 °C to 70 °C for 2 hours is used to prevent melt streaks. Fluoropolymer processing aid at 200 mg/kg to 500 mg/kg is added when die lip deposit appears at extended run times; the exact level is adjusted to avoid plate-out on the chill roll. Edge trim recycle can be incorporated in cast film operations, but the addition level is limited by gel history and film haze rather than by a universal percentage. Screen pack configurations of 20/40/60 mesh are common for cast film; deeper screen layers increase melt temperature and may shift the throughput-limiting constraint from screw speed to screen pressure.

Chill Roll Quench, Die-to-Roll Gap, and Film Optics in Coextruded Cast Structures

Coextruded cast film structures using 1018EA in a core or sub-skin layer are processed with chill roll temperatures between 15 °C and 30 °C. The die-to-roll gap is set to avoid draw resonance while controlling haze and gloss; a wide gap reduces orientation but can increase film curl, while an excessively short gap increases melt roll pressure and can induce edge turbulence. Film haze measured by ASTM D1003-21 and gloss at 45° measured by ASTM D2457-13 are influenced more by chill roll surface finish and air knife velocity than by resin choice alone. In monolayer cast films, 1018EA is used at 20 µm to 50 µm for industrial liners and stretch wrap; in coextruded structures, the resin is typically placed in the core with LDPE-rich skin layers to improve melt stability and surface roughness. Because the grade has low melt strength, it is not a suitable skin layer candidate for high-draw cast film unless blended with LDPE at ratios sufficient to induce strain hardening. When blown film is attempted, bubble stability requires internal bubble cooling, a low stalk height, or blending with LDPE because the grade lacks the long-chain branching that stabilizes the bubble against melt fracture and draw resonance.

When 1018EA Replaces a 0.918/1.0 Ziegler-Natta LLDPE in an Existing Cast Line Without Screw Redesign

When the grade is dropped into an existing cast line designed for ZN LLDPE, the first observable process conflict is usually higher extruder head pressure at constant screw speed. Because the metallocene resin has a narrower molecular weight distribution and lower shear thinning, the pressure drop across a screen pack with 400 mesh layers can rise sufficiently to require either a lower screw speed or a reduction in screen pack density. Output reductions of 5% to 15% are possible on lines without sufficient torque margin; however, published data for this specific configuration is limited. The resin’s lower melt elasticity also reduces die swell, which changes the die-to-roll gap setting needed to maintain the same film thickness profile. If the existing line uses a fixed lip die, the edge bead structure shifts, and die lip opening adjustments should be made in 0.01 mm increments to avoid uneven gauge bands. The additive package of 1018EA may not include slip or antiblock; if the previous grade contained slip, the coefficient of friction measured by ASTM D1894-14 will increase unless external slip is added or the structure is modified. Film blocking behavior must be revalidated with ASTM D3354-15 before specifying the resin for high-speed automated packaging lines.

Compared with ethylene-octene plastomers of similar density, 1018EA has a higher crystalline fraction and therefore higher tensile modulus, lower hot tack force, and a higher seal initiation temperature. Compared with a high-pressure LDPE grade of melt index 0.8 g/10 min and density 0.923 g/cm³, 1018EA exhibits lower melt elasticity, lower neck-in in cast film, and higher resistance to tear propagation measured by ASTM D1922-15. The choice between 1018EA and another Exceed grade of different density is governed by stiffness, seal, and abrasion requirements; the 0.918 g/cm³ density is selected where toughness and optics are weighted above modulus. For producers replacing a specialty plastomer, the seal temperature difference should be measured on the actual line with ASTM F2029-16 rather than inferred from density alone.

In lamination applications, 1018EA is used as a sealant layer or as a core layer in tandem cast lines. Adhesion to oriented polyester or oriented polypropylene cannot be assumed from resin choice alone; the surface is oxidized by corona discharge to a wetting tension of 38 mN/m to 44 mN/m measured by ASTM D2578-17. If lamination is delayed beyond the oxidative half-life of the treated surface, peel strength measured by ASTM D1876-08 degrades, and the failure mode shifts from cohesive to adhesive. For solventless lamination, the resin must be evaluated with the adhesive system because low-molecular-weight migration from the film surface can inhibit urethane cure.

Regulatory documentation for the grade is supplied through the manufacturer's product safety and regulatory data sheets. Under FDA 21 CFR 177.1520(c), the base polyethylene polymer may be used in food contact applications provided the finished film meets extractives specifications and the conditions of use defined in the regulation. For European Union food contact, compliance is assessed under Regulation (EU) No 10/2011 with overall migration limits of 10 mg/dm² or 60 mg/kg for specific food simulants, depending on the final package geometry and use ratio. The grade is subject to REACH registration obligations when imported into the EU; the supplier's safety data sheet should be checked for Candidate List substances. The resin is not a drop-in replacement for all 0.918/1.0 LLDPE grades because additives, comonomer type, and catalyst residues influence organoleptic performance. For direct contact with fatty foods, migration testing using simulant D2 or D1 per Regulation (EU) No 10/2011 is required, and processing aids used on the film line must themselves be food-contact approved.

An additional operational boundary appears in high-cling stretch film. The cling agent in the skin layer is typically polyisobutylene or a low-molecular-weight amorphous polyolefin; 1018EA in the core layer does not require cling modification, but if it is used in the cling layer without additive, the cling force measured by ASTM D5458-95 will be below the typical wrap retention requirement of 50 g for 25 µm film. The resin therefore is specified as a core layer or blend component in high-cling structures. In pre-stretch applications up to 200% elongation, film toughness must be validated by ASTM D882-18 tensile energy to break; published data for this specific configuration is limited. Because 1018EA has a low coefficient of friction in the absence of slip, it is not recommended for surface layers in automatic form-fill-seal operations requiring stable film transport unless an external slip masterbatch is added at a controlled letdown ratio. The final film property profile is inseparable from the processing line configuration: chill roll temperature, die-to-roll gap, and thickness profile collectively determine the measured dart impact, tear, haze, and seal initiation behavior.