LyondellBasell HDPE H6030 is a high-density polyethylene injection-moulding grade. The grade designation H6030 belongs to the LyondellBasell HDPE portfolio and is assigned a nominal melt index of 30 g/10 min and a nominal density of 0.960 g/cm³. The melt index is determined under ASTM D1238 at 190 °C with a 2.16 kg load; density is determined according to ASTM D1505 or ISO 1183-1. The product is supplied as pellets with a standard stabilizer package and is positioned for high-speed injection moulding of thin-wall rigid packaging, closures, overcaps, housewares and related components. Published data for highly specific configurations—such as spiral flow length on a particular tool or grade-specific pressure-volume-temperature curves—is limited in publicly accessible sources; values discussed below are representative of the manufacturer’s technical literature and are not to be used as batch-release limits without verification against the certificate of analysis.

What flow length and injection pressure follow from a 30 g/10 min HDPE melt index?

The 30 g/10 min melt index places H6030 in the low-viscosity range of HDPE. Melt viscosity at 190 °C and at shear rates typical of injection moulding is substantially lower than that of extrusion blow moulding or pipe grades with melt index values of 0.20–0.60 g/10 min. In mould-filling terms, this reduces pressure drop through sprue, runner and gate systems and permits filling of thin sections that would freeze prematurely with lower-flow HDPE grades. The low melt viscosity also reduces plastication torque and allows shorter cycle times in multicavity tooling. However, the same property reduces melt strength and excludes the grade from processes requiring parison hang strength or bubble stability.

On production-scale reciprocating screw injection machines with clamp forces from 500 kN to 3,000 kN, H6030 is processable at melt temperatures of 190–240 °C and mould temperatures of 10–30 °C. A general-purpose polyolefin screw with an L/D ratio of 20:1 to 25:1 and a compression ratio of 2.0:1 to 2.5:1 is adequate. Because high-flow HDPE melts display shear-thinning behaviour at injection shear rates of 100–1,000 s⁻¹, apparent viscosity falls with increasing fill speed. This effect must be accounted for in mould-filling simulation; generic HDPE rheology constants may introduce errors unless validated by short-shot studies on the target tool.

Critical processing thresholds exist. Sustained melt temperature above 240 °C may accelerate depletion of the stabilizer package and generate oxidative by-products, resulting in yellowing, silver streaks or loss of impact properties. Insufficient melt temperature below 190 °C may raise injection pressure and produce premature gate freeze-off in thin sections. Hold pressure and gate seal time must be optimized for each tool because the high crystalline content of the 0.960 g/cm³ density drives solidification shrinkage and can produce anisotropic part dimensions.

When ESCR and slow-crack growth resistance outweigh flow in package qualification

In applications where containers, closures or medical packaging are exposed to surfactants, essential oils, phenolic disinfectants, or hydrocarbon-based fluids, the high density and low-molecular-weight architecture of H6030 impose a corresponding reduction in environmental stress crack resistance relative to lower-density HDPE copolymers and bimodal pipe resins. Environmental stress crack resistance testing under ASTM D1693 or ISO 22088-2 is required for any formulation involving aggressive liquids. The grade is not classified under ISO 9080-derived MRS designations and is not intended for pressure-pipe service requiring long-term hydrostatic strength or slow-crack growth thresholds under ISO 13479.

For thin-wall lids, overcaps and non-load-bearing packaging, the controlling requirement may be short-term flexural stiffness rather than slow-crack growth. The high density of H6030 increases crystalline fraction and flexural modulus, permitting down-gauging in stiffness-driven designs. If impact toughness or ESCR controls part performance, a lower-density injection moulding HDPE in the 0.945–0.955 g/cm³ range should be selected. Failure modes observed on manufacturing lines include cap cracking in detergent environments and warped flat lids after blocking or load under heat; both require validation against the specific chemical and thermal exposure rather than reliance on neat-resin tensile data alone.

A 0.960 g/cm³ density places H6030 at the stiff end of HDPE injection moulding

Because density is 0.960 g/cm³, the crystalline fraction is high relative to HDPE copolymers with densities of 0.940–0.955 g/cm³. The increase in crystallinity raises flexural modulus and surface hardness while reducing notched impact and elongation. Representative mechanical properties from the manufacturer’s technical literature are summarized below. The values are typical and are not specification limits.

A comparison with blow moulding and pipe grades clarifies the structural and rheological placement of H6030. Extrusion blow moulding HDPE grades typically carry melt index values between 0.20 g/10 min and 0.60 g/10 min to maintain parison integrity during extrusion and mould transfer. H6030, at 30 g/10 min, cannot sustain the parison hang strength required for large containers. Pipe grades such as PE 100 are formulated with bimodal molecular weight distributions to satisfy the long-term hydrostatic strength requirements of ISO 9080 and slow-crack growth thresholds of ISO 13479. These architectural differences give pipe resins far higher ESCR than a 0.960 g/cm³ homopolymer. Injection moulding grades with melt indices from 10 g/10 min to 60 g/10 min are used for thin-wall packaging; H6030 sits near the middle of that flow range, while its density provides stiffness that lower-density grades do not reach. The trade-off is reduced ductility and stress-crack resistance.

Comparative resin-class positioning across injection moulding, blow moulding, and pressure pipe HDPE grades

Across the HDPE resin family, melt index, density and molecular weight distribution determine both processing behaviour and service performance. The following table summarizes the placement of H6030 relative to common HDPE classes.

Food-contact and drinking-water applicability are not automatically established by the base resin specification. Compliance with U.S. FDA 21 CFR 177.1520(c) or EU Regulation (EU) No 10/2011 depends on comonomer content, additive package, and migration testing under the intended thickness and temperature profile. Unmodified HDPE is not hygroscopic, but surface condensation from cold storage in high-humidity environments can produce splay; drying at 80 °C for 2 h is usually sufficient if visual defects appear during moulding trials. Production lots should be monitored for melt-index stability, density consistency and closure torque retention because batch-to-batch variation in low-molecular-weight fraction can shift mould filling and sealing behaviour. Published data for specific thin-wall configurations is limited; the processing window for H6030 must therefore be established on the target tool with short-shot studies, gate seal time measurement, and ESCR exposure tests relevant to the final chemical environment.