| HS Code | 656855 |
| Density | 0.918 g/cm³ |
| Melt Flow Rate 190 C 2 16kg | 20 g/10 min |
| Tensile Stress At Yield | 11 MPa |
| Tensile Stress At Break | 12 MPa |
| Elongation At Break | 100% |
| Flexural Modulus | 320 MPa |
| Hardness Shore D | 58 |
| Vicat Softening Temperature | 82 °C |
| Melting Point | 121 °C |
| Brittleness Temperature | -70 °C |
| Crystallization Temperature | 104 °C |
As an accredited SABIC LLDPE 318CNJ factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | SABIC LLDPE 318CNJ is supplied in 25 kg polyethylene bags, palletized and shrink-wrapped for safe handling and transport. |
| Container Loading (20′ FCL) | SABIC LLDPE 318CNJ loaded in 20ft FCL container, secured safely for transport, preventing contamination and damage. |
| Shipping | SABIC LLDPE 318CNJ is a non-hazardous linear low-density polyethylene resin, supplied as free-flowing pellets in 25 kg bags. It ships in clean, dry containers or flexibags, with ventilation and moisture protection advised. No dangerous goods classification applies, but cargo should be stowed away from heat and sharp objects. |
| Storage | Store SABIC LLDPE 318CNJ in a dry, clean, well-ventilated area away from direct sunlight, heat, and ignition sources. Keep bags sealed and upright to prevent contamination and moisture pickup. Avoid dust accumulation and contact with strong oxidizers. No special temperature control is required, but maintain moderate ambient conditions. Handle with care to prevent tearing. |
| Shelf Life | Shelf life is indefinite if stored in a cool, dry place away from direct sunlight and heat sources. |
SABIC LLDPE 318CNJ, an ethylene-butene linear low-density polyethylene with nominal density 0.918 g/cm³ (ISO 1183-1) and melt flow rate 1.0 g/10 min (ISO 1133-1:2022, 190°C, 2.16 kg), is converted in the heavy-duty FFS shipping sack segment on a three-layer blown film line. Extruder equipment comprises 75 mm single-screw barrier screws with L/D 30:1, Maddock mixing sections, 20/40/60 mesh screen packs, 250 mm die, 1.8 mm die gap, twin-lip air ring, and internal bubble cooling. The formulation is 70 wt% 318CNJ in skins and core, 20 wt% LDPE for bubble stability, and 10 wt% HDPE for secant modulus. Barrel temperature profile is 165/175/185/195/200°C, melt temperature at the die is 195–205°C, blow-up ratio is 2.2–2.8, frost line height is 600–900 mm, and output on a 75 mm line runs 180–240 kg/h at screw speed 85–100 rpm. Pre-screen melt pressure is 280–340 bar; melt pressure above 350 bar initiates shark-skin melt fracture due to the grade’s 1.0 g/10 min melt flow rate. The HDPE fraction is capped at 15 wt% because higher HDPE additions reduce ASTM D882-18 elongation at break below 400% in the transverse direction on 50 µm film, producing seam-zone splitting in hot-stab and ultrasonic closing systems. Terminal products are 25 kg and 50 kg FFS sacks for polymer granules, fertilizer, and petrochemical export packaging; seal strength measured by ASTM F88-21 is required to remain above 12 N/15 mm on mineral-filled product seams.
Blown stretch film conversion uses 65 mm barrier-screw extruders, L/D 28:1, 150 mm die, 1.6 mm die gap, and blow-up ratio 2.0–2.5. In a three-layer A/B/C configuration, 318CNJ occupies the core layer at 50–60 wt%, metallocene-catalyzed LLDPE skins occupy 20–25 wt%, and LDPE 10–20 wt% is added to reduce die lip shear stress. The cling layer receives polyisobutylene tackifier concentrate at 2–3 wt%; the non-cling layer receives silica antiblock masterbatch at 1.0–1.5 wt%. The low melt flow rate of 318CNJ increases pre-screen melt pressure at high screw speed, and the die gap must not be reduced below 1.6 mm. At melt temperature below 190°C, shear rate in the die lip exceeds 2000 s⁻¹ and visible melt fracture develops on the outside skin. At melt temperature above 210°C, polyisobutylene tackifier degradation produces microgels, and cling force measured by ASTM D5458-19 drops below 100 g on a 25 mm probe. Power-stretch wrappers require pre-stretch to 200–250%; 318CNJ imparts sufficient elongation because ISO 527-3 elongation at break remains above 500% on 23 µm film. Puncture resistance by ASTM D5748-19 is verified at 23°C on wrapped pallet corners. Terminal products include 450 mm hand rolls, 500 mm machine rolls, and 750 mm jumbo rolls for pallet wrapping in logistics and beverage distribution.
For solvent-based and solventless flexible packaging lamination, 318CNJ is processed as the sealant skin in three-layer coextruded blown film at 60–70 wt%, with LDPE 20–30 wt% in the core and high-molecular-weight LDPE 10 wt% as processing aid. Die gap is 1.8 mm, blow-up ratio 2.3–2.8, melt temperature 190–200°C, and frost line height 500–700 mm. Inline corona treatment sets wetting tension to 38–42 mN/m measured by ISO 8296; wetting tension below 38 mN/m causes adhesive delamination with two-component polyurethane adhesives, while values above 46 mN/m induce blocking during roll storage. Heat-seal initiation is measured on a gradient heat sealer at 0.5 MPa and 0.5 s dwell; seal strength is validated by ASTM F88-21 and hot-tack by ASTM F2622-20. The sealant layer must maintain composite peel adhesion above 2.0 N/15 mm after lamination to reverse-printed BOPP or PET. Food-contact structures must comply with FDA 21 CFR 177.1520 for olefin polymers and EU 10/2011 with overall migration limit 10 mg/dm²; specific migration of slip and antiblock additives must remain within the positive-list restrictions of EU 10/2011 Annex I. Terminal products include stand-up pouches, pillow pouches for dry foods, frozen food bags, and viscous liquid sachets.
Agricultural silage covers and greenhouse films are produced from 318CNJ by blending with HALS/UV-stabilizer masterbatches rather than relying on the as-supplied resin oxidation stability. On a monolayer blown film line with 60 mm barrier screw and die gap 2.2 mm, melt temperature is controlled at 180–195°C to limit stabilizer degradation, blow-up ratio is 2.8–3.2, frost line height is 800–1100 mm, and film thickness is 120–180 µm for silage covers and 180–200 µm for greenhouse cladding. UV masterbatch dosing is 0.8–1.5 wt% for 12-month silage cover service and 2.0–3.0 wt% for multi-season greenhouse exposure. Puncture resistance is assessed by ASTM D5748-19 on weathered film, and tensile retention after accelerated aging is tested by ISO 4892-2; converters typically require ≥50% retention of elongation at break after 4000 h Xenon-arc exposure for 24-month greenhouse use. Published data for this specific configuration and additive masterbatch is limited, and each film structure must be validated through in-house Xenon or QUV testing. Terminal products include round bale silage stretch covers, bunker silo covers, and greenhouse tunnel cladding used in forage preservation and horticultural production.
Shrink-hood film is blown from a formulation of 70 wt% 318CNJ, 20 wt% LDPE, and 10 wt% HDPE on a 90 mm extruder with L/D 30:1, 300 mm die, 2.0 mm die gap, blow-up ratio 3.2–4.0, and melt temperature 190–205°C. Stalk height is maintained at 1000–1400 mm because the high-stalk process preserves transverse orientation; free shrink measured by ASTM D2732-20 at 120°C is typically 55–65% in machine direction and 20–30% in transverse direction. If stalk height falls below 800 mm, transverse free shrink drops below 18%, leaving loose film at pallet corners and reducing load stability during transport. If stalk height exceeds 1600 mm, bubble instability and gauge variation above ±8% create weak bands that split under pallet edge abrasion. Shrink tension and build-up force are verified by ISO 14616; the film is converted into pre-made hoods with corner welding and applied through shrink-hood machinery at 150–180°C hot-air rings. Terminal products include pallet covers for construction materials, appliance export, and chemical drums where high puncture resistance and load-bracing force are required.
| Blown film application | Die gap | Blow-up ratio | Melt temperature | Frost line height |
|---|---|---|---|---|
| Heavy-duty FFS sacks | 1.8–2.2 mm | 2.2–2.8 | 195–205°C | 600–900 mm |
| Blown stretch film | 1.6–2.0 mm | 2.0–2.5 | 190–205°C | 500–800 mm |
| Lamination film | 1.8 mm | 2.3–2.8 | 190–200°C | 500–700 mm |
| Agricultural covers | 2.0–2.4 mm | 2.8–3.2 | 180–195°C | 800–1100 mm |
| Shrink-hood film | 1.6–2.4 mm | 3.2–4.0 | 190–205°C | 1000–1400 mm |
| Frozen food film | 1.8 mm | 2.2–2.6 | 190–200°C | 500–750 mm |
Frozen food packaging structures use 318CNJ as sealant layer and core in three-layer coextruded film with thickness 40–70 µm. The sealant skin is formulated with erucamide slip at 500–900 ppm and silica antiblock at 1000–1500 ppm; die gap is 1.8 mm, blow-up ratio 2.2–2.6, melt temperature 190–200°C, and frost line height 500–750 mm. Slip concentration above 900 ppm reduces coefficient of friction below 0.10 by ASTM D1894-14 and causes roll telescoping on vertical form-fill-seal machines. Low-temperature performance is evaluated by ASTM D1709-16A dart impact and ASTM D882-18 tensile elongation on film conditioned at -18°C; the film is required to retain at least 300% elongation at break in both machine and transverse directions to avoid flex cracks in IQF vegetable bags and frozen meat packs. Food-contact compliance follows FDA 21 CFR 177.1520 and EU 10/2011; the sealant layer must not transfer slip or antiblock above the specific migration limits assigned in EU 10/2011 Annex I. Terminal products include flow-wrap packs for frozen vegetables, pillow bags for frozen seafood, and block-bottom bags for frozen meat portions.
Competitive SABIC LLDPE 318CNJ prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615365186327 or mail to admin@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8615365186327
Email: admin@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
SABIC LLDPE 318CNJ is a butene-comonomer linear low-density polyethylene supplied as pellets for cast film extrusion. The grade is characterized by a nominal melt flow rate of 2.8 g/10 min determined at 190 °C under 2.16 kg load according to ISO 1133-1:2022 and a nominal density of 0.918 g/cm³ according to ISO 1183-1:2019. The comonomer is 1-butene, which produces a broader molecular weight distribution than metallocene-catalysed grades and a lower melt strength than high-pressure LDPE. In cast film operations, the melt flow rate of 2.8 g/10 min places the resin in the medium-flow LLDPE range; this reduces specific energy consumption relative to 1.0–2.0 g/10 min film grades and permits thinner die gaps without excessive melt pressure.
The resin is typically processed on cast film lines equipped with single-screw extruders of 75–120 mm diameter and L/D 30:1 to 33:1. Published processing guides recommend die-lip melt temperatures of 240–280 °C; the lower portion of this range is preferred when optical clarity and thermal stability are controlling. The nominal density of 0.918 g/cm³ provides a balance between stiffness and impact toughness in thin-gauge cast film, while the butene comonomer contributes to lower crystallinity than a homopolymer of equivalent density.
In high-speed cast film extrusion, the primary processing constraints are draw resonance, melt fracture, and thermal degradation. Draw resonance, an oscillation in web thickness and width above a critical draw ratio, is governed by melt strength and the die-to-chill-roll air gap. Because 318CNJ is a butene LLDPE with a broader molecular weight distribution and 2.8 g/10 min MFR, its extensional viscosity is lower than that of LDPE and lower-MFR LLDPE grades. Production-scale observations on 90 mm single-screw extruders with barrier screws and 0.8 mm die gaps indicate that stable webs are obtained at line speeds of 150–250 m/min when the air gap is maintained below 15 cm and the chill roll temperature is held at 20–30 °C. At air gaps above 20 cm, draw resonance becomes more probable and gauge uniformity is compromised.
Extruder temperature profiles are typically set with a feed zone of 180–200 °C, a compression zone of 220–240 °C, a metering zone of 240–260 °C, and die zones of 250–270 °C. Melt pressure before the screen pack on a 90 mm extruder should not exceed 350 bar; higher pressures indicate screen blinding, insufficient barrel temperature, or an excessively restrictive die gap. Screw speed and output are balanced to maintain specific energy below 0.25 kWh/kg on a grooved-feed extruder. Thermal degradation of the butene copolymer begins to generate gel particles and discolouration above 300 °C; residence time at maximum barrel temperature should be limited to 15 min. Cast film edge trim is generally recycled at 10–20 % by weight; 318CNJ tolerates this regrind level without significant reduction in dart impact because the butene comonomer reduces crystallinity at 0.918 g/cm³.
Typical cast film properties for 318CNJ at 30 µm gauge are reported by the manufacturer according to the following standards: tensile properties by ISO 527-3, Elmendorf tear by ISO 6383-2, dart impact by ISO 7765-1, and haze by ASTM D1003. At 30 µm, typical dart impact F50 is 85 g, machine-direction Elmendorf tear is 150 g, transverse-direction tear is 350 g, and haze is 4 %. Tensile stress at break in the machine direction is typically 35 MPa with elongation at break of 700 %; transverse-direction tensile stress at break is 30 MPa with elongation at break of 800 %. The secant modulus at 1 % strain is approximately 200 MPa in both directions. The values are typical data and are not specification limits.
| Property | Test method | Typical value |
|---|---|---|
| Melt flow rate | ISO 1133-1:2022 | 2.8 g/10 min |
| Density | ISO 1183-1:2019 | 0.918 g/cm³ |
| Tensile stress at break, MD | ISO 527-3 | 35 MPa |
| Tensile stress at break, TD | ISO 527-3 | 30 MPa |
| Elongation at break, MD | ISO 527-3 | 700 % |
| Elongation at break, TD | ISO 527-3 | 800 % |
| Elmendorf tear, MD | ISO 6383-2 | 150 g |
| Elmendorf tear, TD | ISO 6383-2 | 350 g |
| Dart impact F50 | ISO 7765-1 | 85 g |
| Haze | ASTM D1003 | 4 % |
| Gloss at 45° | ASTM D2457 | 75 |
| Vicat softening temperature | ISO 306 | 93 °C |
The property balance reflects the butene comonomer content and the density of 0.918 g/cm³. The layer structure, monolayer or coextruded, changes tear propagation and optical performance. In monolayer cast film, transverse-direction tear is typically higher than machine-direction tear because of preferential machine-direction orientation; the ratio of 350 g to 150 g is consistent with that orientation. Optical haze of 4 % is achieved only when the chill roll temperature is maintained below 30 °C and die-lip cleanliness is controlled. If the chill roll temperature rises above 35 °C, the film surface develops a more random crystalline texture and haze increases measurably. Thermal resistance is limited to the Vicat softening temperature of approximately 93 °C; therefore the resin is not recommended for retort packaging or hot-fill service above 80 °C.
In coextruded cast film structures, 318CNJ is used as a skin or core layer in combination with LDPE, metallocene LLDPE, or ethylene-vinyl acetate copolymers. The resin’s apparent viscosity at 250 °C and 100 s⁻¹ shear rate is approximately 120 Pa·s; this value allows layer distribution to remain stable at channel widths of 1.0–1.5 mm in multi-manifold dies. If a skin-layer melt temperature falls below 240 °C, interfacial layer distortion can occur when it is paired with a metallocene LLDPE of higher viscosity. In contrast, blown film permits greater bubble-diameter and frost-line adjustments to correct gauge variation, but cast film requires die-bolt and deckle adjustments at the die lip. Published data for specific coextrusion combinations with 318CNJ is limited; layer-ratio trials are therefore required to establish gauge control on a given production line.
Compared with high-pressure LDPE of similar melt flow rate, 318CNJ has lower melt strength and lower shear viscosity at high shear rates. Extrusion pressure on a 90 mm extruder is typically 20–30 % lower when processing 318CNJ than when processing an LDPE of 0.923 g/cm³ density at the same barrel temperature. This pressure reduction permits higher screw speed before reaching maximum drive load, but it also reduces bubble stability in blown film and increases the tendency for web sag in cast film. Compared with metallocene LLDPE of equal density and melt flow rate, 318CNJ generally shows lower dart impact and lower puncture resistance. The difference arises from the broader composition distribution in a Ziegler-Natta butene resin; metallocene resins have more uniform comonomer placement and fewer highly crystalline fractions. The trade-off is processability: 318CNJ typically displays lower extrusion pressure and reduced melt fracture tendency than metallocene grades at equivalent output. For applications requiring dart impact above 150 g at 30 µm, a hexene metallocene LLDPE or a blend may be required.
When 318CNJ is substituted for LDPE in a cast lamination or thin-gauge packaging line, the die gap is often reduced from 0.8–1.0 mm to 0.5–0.8 mm because the lower melt strength of LLDPE causes neck-in. Chill roll temperature should be lowered to 20–25 °C to stabilize the web. The air gap between die lip and chill roll must be minimized to 8–15 cm. At these settings, the output rate of a 90 mm extruder can be maintained at 200–300 kg/h with gauge variation below 2 %; however, edge trim waste may rise because LLDPE neck-in is greater than LDPE neck-in. The higher melt flow of 2.8 g/10 min permits the use of a lower melt temperature by 10–20 °C relative to LDPE grades of similar density, which helps to preserve organoleptic neutrality in food-contact film.
For food-contact use, 318CNJ is typically evaluated against FDA 21 CFR 177.1520 and EU Regulation (EU) No 10/2011, with overall migration limits specified in Article 6 and Annex I of the EU regulation. The grade is not hygroscopic; pre-drying is not required when stored indoors at relative humidity below 60 %. If surface condensation from outdoor storage occurs, drying for 1–2 h at 70–80 °C using a desiccant dryer is sufficient. The resin should not be processed at melt temperatures above 300 °C for extended periods because butene copolymers generate gel particles and discolouration. Regrind content above 30 % by weight may reduce dart impact in film below 50 µm. The following matrix summarizes the principal test and compliance anchors relevant to incoming inspection and regulatory documentation.
| Matrix item | Standard or regulation | Test or scope |
|---|---|---|
| Melt mass-flow rate | ISO 1133-1:2022 | 190 °C, 2.16 kg |
| Density | ISO 1183-1:2019 | Immersion method |
| Film tensile properties | ISO 527-3 | Machine and transverse direction |
| Elmendorf tear resistance | ISO 6383-2 | Machine and transverse direction |
| Dart impact resistance | ISO 7765-1 | F50 method |
| Optical haze | ASTM D1003 | Cast film specimen |
| US food-contact resin | FDA 21 CFR 177.1520 | Olefin polymer compliance |
| EU plastic food-contact | EU Regulation (EU) No 10/2011 | Overall migration and composition |
| Heavy metals in packaging | EU Directive 94/62/EC | Sum of lead, cadmium, mercury, chromium VI |
In a monolayer cast film line running 30 µm packaging film, the extruder barrel temperature profile, die gap, air gap, and chill roll temperature are the main variables controlling gauge uniformity and optical quality. When 318CNJ is run at a barrel profile of 180/220/250/260 °C with a 0.8 mm die gap, 12 cm air gap, and 25 °C chill roll, the web stabilizes at line speeds up to 200 m/min without draw resonance. Increasing the die gap to 1.0 mm while maintaining the same output lowers die shear rate and reduces the risk of melt fracture, but increases the required draw ratio and may widen the neck-in angle. The use of a vacuum box or air knife at the die lip is recommended when line speed exceeds 250 m/min; this equipment pins the melt curtain to the chill roll and reduces gauge variation caused by air entrainment.
