HANWHA LLDPE 4300S is a butene-based linear low-density polyethylene resin supplied by Hanwha Total Petrochemical for thin-gauge blown-film and cast-film conversion. The grade is positioned for applications requiring moderate stiffness, controlled slip, and stable bubble behaviour at commercial line speeds. Representative product literature lists nominal density at 0.921 g/cm³ measured by ISO 1183-1:2019 and nominal melt flow rate at 1.0 g/10 min under 190 °C/2.16 kg load in accordance with ISO 1133-1:2022. These values are not contractual sale specifications; lot-specific certificates of analysis govern all acceptance testing. The product is supplied as cylindrical pellets and may contain slip and antiblock additives depending on regional formulation. Processors must confirm additive loading against lot documentation when coefficient of friction and clarity are critical.

The tabulated values derive from conditioned granules and 25 µm tubular film; they are not automatically predictive for coextruded structures, thick sheets, or heavily pigmented films. For conversion troubleshooting, the melt-flow-rate-to-density ratio serves as a rough indicator of melt extensibility and crystalline stiffness. On grooved-feed extruders with 25:1 L/D barrier screws, stable bubble formation is typically observed at melt temperatures between 190 °C and 225 °C. Below 185 °C, sharkskin and freeze-line roughness become more probable. Increasing die gap from 1.2 mm to 1.8 mm and raising die temperature to 210 °C suppresses this defect without damaging optical haze. Blow-up ratios of 2.0:1 to 3.0:1 are practical for monolayer structures. At higher blow-up ratios, transverse elongation increases while machine-direction tensile strength decreases; bubble-width tensile measurements under ISO 527-2:2012 show typical MD/TD yield values of 11 MPa/12 MPa at 25 µm.

On cast-film lines, the resin processes at melt temperatures from 220 °C to 260 °C with die gaps between 0.5 mm and 0.8 mm. Edge-necking and draw resonance are controlled by adjusting draw ratio and air-knife position. Because the melt flow rate of 1.0 g/10 min is higher than that of film grades in the 0.5 g/10 min range, screw backpressure on a 90 mm single-screw extruder with 28:1 L/D is reduced by approximately 8% under identical screw-speed conditions. This comparison is equipment-specific and should not be extrapolated to grooved-feed machines without pressure-transducer verification.

What Physical Property Metrics Govern Film Conversion and End-Use Performance?

The practical conversion window for HANWHA LLDPE 4300S is controlled by melt temperature, die gap, frost-line height, and molecular-weight distribution. The resin exhibits a broader comonomer distribution than single-site catalysed C6-LLDPE, which contributes higher melt strength and more stable bubble geometry at blow-up ratios up to 2.5:1. This melt strength is advantageous in high-stalk extruders, where excessive sag would otherwise lead to gauge variation. However, the broader distribution also produces slightly higher haze than metallocene references when film is quenched too rapidly. Optical homogeneity is best maintained when the frost-line height is held between 100 mm and 200 mm above the die exit on a conventional air-ring-cooled line. Frost-line movement outside this band increases haze scatter measured at 25 µm by approximately 1.5% absolute, although the exact change depends on ambient temperature and air-ring pressure.

Mechanical property development is influenced by orientation during bubble expansion. Machine-direction tear strength is sensitive to draw-down ratio; excessively high draw-down ratio below the frost line reduces Elmendorf tear in the machine direction. In side-by-side trials on a 3-layer blown-film line, films containing 35 wt% 4300S in the core layer with LDPE skins retained seal initiation temperature within 3 °C of the LDPE reference while increasing tensile modulus by approximately 12%. Seal strength tests were performed at 110 °C dwell temperature and 0.5 s dwell time. Published data for this specific configuration is limited; processor-run trials are required before commercial specification.

When Gel Defects and Melt Fracture Limit Output in High-Speed Blown-Film Lines

Field observations on high-output lines indicate that gel counts above 150 particles/m² of 200 µm maximum dimension are most frequently traceable to melt-temperature excursions above 240 °C or prolonged residence time in the die adapter. HANWHA LLDPE 4300S exhibits broader molecular-weight distribution than single-site C6-LLDPE; consequently, excessive shear near the die land can generate optical haze without measurable cross-linked gel. When gel defects appear, the first corrective action is to lower adaptor and die temperatures to 210 °C and reduce screw speed to maintain residence time below 120 s. On cast-film dies, flow-channel stagnation at edge zones produces additive migration and die-lip buildup. Purging with a higher-MFR LDPE at 2.0 g/10 min after every 72 h of continuous operation reduces hydrocarbon oxidation residue and lowers the incidence of edge gels.

Pre-drying is not routinely required. However, storage at relative humidity above 60% followed by immediate processing can introduce steam bubbles in the melt film. In those conditions, pellets should be dried at 70 °C for 2 h using a dehumidifying dryer with dew point below -30 °C. Avoid combining the resin with amine-based process stabilizers or high levels of acid scavengers because the resulting additive interactions can shift the coefficient of friction and reduce heat-seal strength at 110 °C. Blown-film output rates beyond 300 kg/h on a 90 mm extruder may require die-pressure monitoring to prevent melt fracture at the die-lip exit.

Regulatory Compliance Matrix for HANWHA LLDPE 4300S

Food-contact compliance must be evaluated on the finished article, not on the resin alone. Additive masterbatches, printing inks, and lamination adhesives influence overall migration. HANWHA LLDPE 4300S is not certified for pharmaceutical primary packaging or implantable device contact without additional qualification.

Differences from other products in the HANWHA film portfolio are material-specific. Compared with lower-melt-flow film grades, 4300S operates in a lower-viscosity envelope, which reduces screw motor load and permits faster screw recovery in high-output lines. Compared with metallocene C6-LLDPE, the butene backbone of 4300S provides higher melt strength but lower dart impact and lower puncture energy at equivalent film gauge. The ASTM D1709-20 dart drop value of 110 g for 25 µm film is not directly comparable to octene-LLDPE references that may exceed 180 g because comonomer type and orientation modify fracture resistance. Published head-to-head values for all HANWHA film grades are limited; processor-run trials under normal production conditions are required before specification changes.

Compared with conventional autoclave LDPE, 4300S exhibits higher tensile strength, better environmental stress-cracking resistance, and higher heat-seal strength at equivalent gauge. However, LDPE retains superior bubble stability in thick-gauge shrink and heavy-duty applications because of long-chain branching. The linear structure of 4300S also produces narrower melt-strength collapse at very low melt temperatures. Therefore, high-stalk operations that convert LDPE below 180 °C must verify that die pressure and amp draw remain stable before substituting 4300S. In coextrusion, 4300S is generally placed in the core layer or in one skin layer where its seal characteristics and additive package do not dominate surface performance. The specific slip and antiblock loading relative to a non-slip film resin shifts the static coefficient of friction by approximately 0.2 units, measured using ASTM D1894-14; processors must confirm that this change is acceptable for downstream form-fill-seal machine throughput.