Indian Oil (IOC) HDPE G-LENE I50A180 is a high-density polyethylene injection-moulding grade supplied in pellet form. The grade designation identifies an injection-moulding resin with a nominal density of 0.950 g/cm³ and a nominal melt flow index of 18 g/10 min measured at 190 °C under a 2.16 kg load according to ASTM D1238 / ISO 1133-1:2022. The product is positioned for high-flow thin-wall moulding where short filling time, low residual stress, and dimensional repeatability are primary requirements. Because melt strength is lower than blow-moulding and film-extrusion HDPE grades, I50A180 is not intended for continuous parison extrusion, blown film, or pipe. Typical evaluation targets include housewares, thin-wall food containers, caps, closures, and technical components with section thickness commonly below 2.0 mm.

Material Specifications and Rheological Positioning

Typical values reported by the producer are lot-dependent and do not replace certificate of analysis limits. The 18 g/10 min MFI places the grade among higher-flow injection-moulding HDPE resins and indicates lower melt viscosity than 4 g/10 min injection grades. Density at 0.950 g/cm³ corresponds to the stiffness and crystallinity expected for high-density polyethylene while retaining sufficient flexibility for thin-wall part ejection. The following table consolidates typical physical properties with the relevant test designations.

Injection-moulding operations using I50A180 generally begin with a barrel profile based on high-flow HDPE. A common starting-point profile from feed to nozzle is 180 °C, 200 °C, 210 °C, and 220 °C, with nozzle temperature at 220 °C. Mould temperature is usually maintained between 10 °C and 30 °C for thin-wall solidification. These values are starting points only and must be adjusted for screw diameter, L/D ratio, shot weight, hot-runner balance, and gate design. The 18 g/10 min MFI permits lower melt temperature than 4 g/10 min HDPE at equivalent injection velocity, but excessively low temperature increases injection pressure and molecular orientation. Screw rotation speed and back pressure should be set to avoid shear heating above 250 °C at the nozzle, and residence time at melt temperature should not exceed 8 min to limit oxidative degradation. Pre-drying is not normally required for this grade; if pellet surface moisture is observed after external storage, hopper drying at 80 °C for 2 h may be applied. A general-purpose polyolefin screw with L/D ratio 20:1 to 24:1 and compression ratio 2.5:1 to 3.0:1 is adequate for most applications.

How Does the Melt Flow Index Affect Tool-Pressure Demand?

The melt flow index of 18 g/10 min places I50A180 among the lower-viscosity injection HDPE grades. In short-flow geometries governed by Poiseuille-dominated melt flow, pressure drop scales inversely with melt flow at constant geometry and temperature. For a given multi-cavity tool, the grade is therefore expected to reduce filling pressure relative to a 4 g/10 min HDPE at similar shot weight. The practical effect appears as a wider processing window in designs with nominal wall section below 1.2 mm, where flow-length-to-wall-thickness ratios above 120:1 are often required. Higher MFI, however, is associated with reduced molecular weight, lower melt strength, and generally lower environmental stress crack resistance. Converters must not transfer low-pressure filling data to aggressive chemical service without conducting ESCR validation according to ASTM D1693 or an equivalent internal protocol. Compared with lower-MFI injection grades such as G-LENE I50A040 at 4 g/10 min, I50A180 reduces melt-pressure demand but sacrifices impact strength and stress-crack resistance in demanding industrial container service.

Thin-wall dairy containers with wall thickness between 0.8 mm and 1.5 mm place simultaneous demands on fill speed and dimensional stability. In short-shot studies, the fill pattern of I50A180 is generally balanced when gate geometry is sized to avoid jetting; tab or edge gates with land lengths below 0.75 mm are typical. Because high-density polyethylene shrinkage is non-isotropic, post-mould dimensional checks should be carried out after 24 h conditioning at 23 °C according to ISO 291. Flow-direction shrinkage may differ from transverse shrinkage by 0.1% to 0.4% depending on processing conditions; published data for this specific configuration is limited. Cap and closure moulding requires additional validation for environmental stress cracking from oils, detergents, and carbonated beverage contact. I50A180 has the required flow for thin-wall closure skirts, but closure designs with aggressive product exposure should be tested under simulated service rather than evaluated by MFI alone. Regrind use is generally permissible up to 20% when the regrind is dry and free of contamination; higher levels may alter MFI, colour, and lot-to-lot consistency.

Mould Filling Behaviour in Multi-Cavity Hot-Runner Tooling

Hot-runner systems with valve-gated drops and manifold temperatures from 220 °C to 250 °C require a resin with sufficiently low melt viscosity to prevent premature freeze-off in small drops. The 18 g/10 min MFI of I50A180 is compatible with hot-runner configurations in which colour changes are infrequent and purge management is controlled. In multi-cavity tools with 16 to 48 cavities, cavity-to-cavity imbalance is governed less by resin choice than by runner layout, gate dimensions, and venting. The resin does not correct tooling-induced imbalance; cavity pressure sensors and runner pressure transducers are used to confirm repeatability. Specific injection pressure requirements scale with cavity projected area, gate size, and melt temperature, and no single pressure value applies across tool designs. Cold-runner systems may also be used, but flow length should be verified because high MFI does not eliminate the need for adequate venting and gate geometry.

Food-contact applications require confirmation that the specific pellet lot meets the intended regulatory status. HDPE grades of this type are commonly evaluated under FDA 21 CFR 177.1520 and EU Regulation (EC) No 10/2011, but compliance is a function of the finished article’s additives, processing aids, colourants, and migration conditions. Documentation should be requested from the producer for the specific grade and lot. The grade is supplied as a base resin without colourants; addition of masterbatch can alter migration behaviour and should be evaluated separately. For non-food technical applications, compliance with REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU may be relevant. The following matrix summarises the typical regulatory instruments that converters may apply; it does not replace article-specific conformity testing.

Regulatory Compliance Checklist and Verification Points

When Cooling Time Governs Cycle Economics in Stack-Mould Production

Stack-mould production of caps and thin-wall containers is highly sensitive to cooling time. The high MFI of I50A180 allows melt temperature at the nozzle to be held at the lower end of the HDPE injection range, which reduces heat load and can shorten cooling time compared with lower-MFI HDPE. Cooling time in a part with wall thickness 1.0 mm is controlled primarily by mould temperature and part thickness, not by resin MFI alone; heat transfer is governed by conduction through the polymer and tool steel. Moulders often set mould temperature at 15 °C to 25 °C for I50A180 to achieve dimensional stability. Demoulding is generally performed at part surface temperatures below 70 °C to prevent sink marks and warpage. Crystallisation shrinkage continues after demoulding, and final dimensions should be assessed after conditioning. Gate freeze time must be established by short-shot and seal-time trials rather than by generic HDPE data. The allowable operating window narrows when cycle time targets fall below 6 s in high-speed closure tools; cavity-pressure sensors and in-mould temperature probes are used to detect gate stringing, part distortion, and inconsistent packing. Published data for this specific configuration is limited, so production validation is mandatory.

Compared with pipe-grade HDPE resins with MFI below 0.5 g/10 min, I50A180 has lower melt strength and is unsuitable for pressure pipe extrusion or large blow-moulded containers. Compared with polypropylene homopolymer of similar flow, this HDPE grade offers lower melting point, lower stiffness, and generally lower upper service temperature; the choice between HDPE and polypropylene must follow end-use requirements for thermal exposure, chemical resistance, and impact. For detergent-resistant closures, ESCR validation is carried out with the actual product contact medium because the base datasheet does not specify a universal ESCR value. The operational boundary for I50A180 excludes prolonged outdoor UV exposure without stabilisation; if outdoor service is required, addition of carbon black masterbatch at 2% to 3% or UV stabiliser is necessary, and mechanical retention should be tested according to ASTM D2565 or ISO 4892-2.