Braskem (Quattor) HDPE HS-5010 is a high-density polyethylene extrusion blow moulding resin within the Braskem HDPE portfolio. The Quattor designation reflects the lineage of Brazilian petrochemical production assets integrated into Braskem’s polyolefin platform. The grade is specified for rigid packaging and technical containers in which parison stability, environmental stress-crack resistance, and stiffness must be balanced. The trade name does not encode a viscosity number or a melt flow index; the product is defined by manufacturer lot data reported against ISO 1133-1:2022 for melt mass-flow rate at 190 °C with a 2.16 kg load, and ISO 1183-1:2019 for density. For HDPE blow moulding resins of comparable application scope, density is commonly observed between 0.945 g/cm³ and 0.957 g/cm³, while melt flow rate typically falls between 0.20 g/10 min and 0.60 g/10 min. Grade-specific limits should be taken from the HS-5010 certificate of analysis rather than from generic trade literature.

The main technical distinction of HS-5010, relative to commodity HDPE film or injection-moulding grades, lies in its molecular architecture designed for hanging parison uniformity and bottle wall-thickness control. Extrusion blow moulding does not subject the polymer to the same high-shear, short-fill-time conditions as injection moulding; instead, the material must retain a high melt strength at low shear rates, resist gravitational sag after the die exit, and deliver controlled swell at the die gap. Environmental stress-crack resistance is generally measured by ASTM D1693-15 bent-strip method; a complementary full-notch creep test is available as ISO 16770. The inherent resin properties are converted into container performance through processing: parison shear and swell, melt temperature, die gap, and accumulator timing all influence final top-load and drop-impact response. Consequently, certification of HS-5010 at the polymer level does not replace finished-ware qualification under ASTM D2659 for column crush and applicable UN packaging test regimes for hazardous goods transport where required.

Published data for this specific grade configuration is limited for high-resolution capillary rheology and long-term creep; generation of lot-specific data under ISO 11443 and ISO 899-2 is required when predictive simulation of wall thickness or bottle deformation is part of the design gate. The product is supplied as pellets and is intended for processing on conventional extrusion blow moulding machinery; it is not a drop-in replacement for every HDPE blow moulding grade because stabiliser package, molecular-weight distribution, and die swell behaviour can vary between production campaigns.

What Limits the Use of HS-5010 in Thin-Wall Extrusion Blow Moulding?

In thin-wall applications with target wall thickness below 0.7 mm, the material must be processed with narrower melt-temperature and die-gap tolerances because melt strength limitations and parison sag can produce high wall-thickness variability. On continuous shuttle lines using screws with 24:1 to 30:1 L/D ratio, barrel temperatures for HDPE blow moulding are generally profiled from 170 °C in the rear zones to 200–220 °C in the front zones, with head and die zones held between 190 °C and 210 °C. These operating boundaries help preserve molecular weight during plastication and reduce gel or shark-skin defects. Equipment with insufficient die-head temperature control or non-uniform barrel heaters may introduce melt streaks that appear as thin spots in the parison.

Parison sag is the central limiting variable. At low melt temperatures, melt fracture may appear as surface roughness; at high melt temperatures, melt strength falls and the parison elongates under its own weight. The practical result is that bottle wall thickness distribution changes before melt flow rate changes enough to correct throughput. Blow moulding grades such as HS-5010 are not selected solely by MFR. Die swell and parison flare are additional low-shear melt properties that determine diameter and length conformance; the acceptable range is established using a weight-drop or pre-form measurement during start-up, not from MFR data alone. The grade’s ESCR and top-load balance is also affected by molecular weight distribution, which is only partially reflected in standard melt index.

When HS-5010 is run in multi-cavity or thin-wall moulds, mould temperature should be maintained between 10 °C and 25 °C to stabilise the snap-off line and reduce warpage; inadequate cooling increases cycle time and allows the bottom flash to smear. Blow pressure in HDPE extrusion blow moulding is commonly set between 0.45 MPa and 0.70 MPa; higher pressure may be needed for larger containers when the parison is stretched over a large cavity, but excessive pressure can force polymer through tooling mismatches and create flash. The use of parison programming, with at least 10 profile points on the die gap, is required for part weights above approximately 1.0 kg to adjust wall thickness for pinched-off corners and handle regions. HS-5010-specific process sheets should override these general ranges when they conflict with manufacturer lot data.

Melt fracture and die swell are not captured by melt flow rate

A single-point melt flow rate at 190 °C and 2.16 kg does not capture the melt elasticity that governs blow moulding performance. In HDPE blow moulding resin evaluation, die swell is a melt-memory phenomenon arising from orientation and relaxation of entangled chains in the die land. If the die land length is too short or the shear rate through the die gap is too high, the parison can exhibit uncontrolled flare or surface defects that force downgauging or scrap generation. Capillary rheology under ISO 11443 provides an entry pressure loss and shear viscosity curve across the relevant shear-rate window; the Bagley correction and Rabinowitsch correction are used to calculate true wall shear stress and true shear rate. Without these corrections, machine operators may misdiagnose die swell variation as a temperature-control problem when it is actually a resin rheology or die-land issue.

Melt fracture in HDPE extrusion blow moulding appears as a rough, matte, or elastically distorted parison surface. In commercial tooling, die-land shear rates are often in the range of 100 s⁻¹ to 500 s⁻¹, which is far above the shear rate of an ISO 1133-1 melt index test. The critical shear rate for onset of melt fracture depends on die geometry, melt temperature, and molecular-weight distribution. Process corrections include raising the die-head temperature within the allowed upper boundary, reducing screw speed, opening the die gap, or using a longer die land to increase relaxation time. If such corrections do not eliminate surface roughness, the cause may be excessive regrind content, presence of unmelted gels from the feed, or a change in stabiliser package that modifies wall-slip behaviour at the die wall.

Die swell and parison sag must also be separated during process diagnosis. Die swell is a radial recovery effect at the die exit; parison sag is a time-dependent elongation under gravitational load. A resin can show high die swell and still sag quickly if its extensional viscosity is low, or it can show low die swell and excellent hang time if its high-molecular-weight tail is broad. For this reason, blow moulding processors use vertical parison hang tests at fixed die gaps and pin temperatures. These tests are equipment-specific and are normally conducted at hang times of 2 s, 5 s, and 8 s to define an operational sag curve. The resulting curve is more useful than the melt index for predicting wall-thickness distribution in a new tool.

On accumulator-head machines used for large industrial containers, the plastication rate and shot size determine hold-up time in the melt pot. HDPE grades with medium melt-flow characteristics such as HS-5010 demand residence-time control because prolonged exposure above 220 °C can accelerate thermo-oxidative degradation. In production lines equipped with 25:1 L/D barrier screws and Maddock-style mixing sections, the typical compression ratio for HDPE blow moulding is 2.2:1 to 2.8:1, and screw speed is adjusted to keep the melt temperature at the die below 220 °C without excessive shear heating. In continuous shuttle lines, mould closing and transfer cycles must synchronise with parison length; the cylinder sequences are not material-specific but the parison weight repeatability is.

From a melt-rheology perspective, the low-shear melt viscosity and the shear thinning exponent are more informative than the single-point melt flow rate. Capillary rheometry according to ISO 11443 is performed at 190 °C, 210 °C, and 230 °C across shear rates from 10 s⁻¹ to 1000 s⁻¹ to define a pseudo-plastic index and an activation energy for flow. The resulting data support simulation of screw pressure, die pressure, and parison swell in blow moulding software. For HDPE, pressure drop through a converging die often scales with the area reduction ratio and the shear rate at the land; unvalidated simulations can underpredict die swell and produce short-shots or underweight bottles. HS-5010 should not be evaluated by MFR alone because a single-point capillary measurement at 2.16 kg is not representative of die-land shear rates, which can exceed 100 s⁻¹ to 500 s⁻¹ in actual tooling.

Regrind integration is a further production-scale concern. In blow moulding, trimmed flash is commonly returned to the feed throat at 15 % to 35 % by weight, with the upper limit governed by the level of gel contamination, colour consistency, and loss of ESCR after multiple heat histories. In HS-5010, as with similar HDPE blow moulding grades, the level of stabiliser in virgin pellets is formulated to tolerate a defined number of regrind cycles, but repeated heating above 220 °C consumes the primary antioxidant and shortens shelf life. The onset of oxidation can be monitored by oxidative induction time under ISO 11357-6. Drying is not normally required for olefinic resins; however, cold pellets exposed to high ambient humidity can develop surface moisture, and a hopper dryer at 70–80 °C may be used when surface splay appears during start-up after storage in unheated silos.

Characterisation and Compliance Reference Set for HDPE HS-5010

The following reference set is used to characterise HDPE blow moulding grades such as HS-5010. The table does not list grade-certified values; it lists the measurement basis that should appear on a technical datasheet or certificate of analysis. Unless otherwise stated, specimens are conditioned at 23 °C and 50 % relative humidity before mechanical testing.

Compliance for food contact in the United States is tested under 21 CFR 177.1520; for European food contact, Regulation (EU) No 10/2011 applies with overall migration testing under EN 1186-1. Grade-specific food-contact status must be confirmed from the Braskem product stewardship bulletin because additives and catalyst residues can shift with production campaign. Under REACH, the grade is a mixture of polymer and additives; the final article manufacturer carries obligations for SVHC communication under Article 33 of Regulation EC 1907/2006 when applicable. RoHS Directive 2011/65/EU restrictions on lead, cadmium, mercury, and hexavalent chromium are generally met by olefinic polymers, but pigment masterbatches used downstream can alter the final declared status.

Comparative selection against unimodal HDPE begins with the trade-off between stiffness and ESCR. A higher-density HDPE of 0.957 g/cm³ can increase flexural modulus and top-load, but the same density elevation tends to shorten ESCR under ASTM D1693-15. HS-5010 is positioned to address that conflict through molecular-weight and comonomer architecture, not merely through density. This is why direct substitution on density alone is inadequate. In bottle specifications, a minimum ESCR of 100 h to 600 h under 100 % Igepal may be set for aggressive household hard-surface cleaner formulations; a high-density grade that meets modulus but fails ESCR will cause field failure through stress cracks at the pinch-off or handle bridge. The specifying engineer should compare notched ESCR, not softening point, when replacing a competitive HDPE blow moulding resin.

In relation to higher-MFR HDPE injection-moulding grades, HS-5010 has a significantly lower single-point melt index and a higher melt strength. Injection-moulding HDPE used for thin-wall containers may have an MFR above 20 g/10 min; extrusion blow moulding grades are generally below 1.0 g/10 min. That difference reduces machine throughput but preserves the parison hang time required to form large preforms. In relation to commodity film grades, HS-5010 is not optimised for blown film drawing or high-stalk bubble stability; the molecular-weight distribution and additive package are targeted for thick-walled molten preforms, not for low-thickness film gauges below 50 µm. The die swell and melt strength values that make HS-5010 suitable for bottle pinch-offs can create unstable bubble frost lines if it is incorrectly run on film lines.

Within the Braskem HDPE blow moulding range, HS-5010 is differentiated from lower-density or higher-melt-flow blow moulding grades by its intended balance of processability and chemical resistance. However, published data comparing all HS-series grades is limited; side-by-side evaluation should be conducted on the same blow moulding line using the same tooling and parison programmer settings. This is because container performance is path-dependent: two HDPE grades with identical density and MFR can produce different wall-thickness profiles if their shear viscosity and die swell differ. The relevant comparative methods include ISO 11443 capillary rheometry, ASTM D3835 for melt rheology at low shear, and ISO 16770 full-notch creep testing for slow crack growth.

When HS-5010 Replaces a Lower Melt-Index HDPE in Large-Part Tooling

When HS-5010 replaces a lower melt-index HDPE in large-part tooling, the immediate processing changes occur in head pressure, torque, and parison sag. A lower melt-index resin typically displays a higher melt viscosity at the die and can hold a parison for longer without sag; a move to HS-5010 may require a parison programmer advance and possible reduction of die gap to retain the same parison length. The accumulator head should be sized with sufficient plastication capacity so that the shot is plasticated within the cycle without holding melt in the head for longer than necessary. Large-part blow moulding of components with wall thickness above 3 mm often uses a blow-up ratio of 2:1 to 4:1; deviations in die swell are amplified by the square of the blow-up ratio for local wall thickness. Therefore, process validation after any resin substitution must include sectioning of the parison and measuring wall thickness at the corners, sidewall, and pinch-off seam.

The differences are not restricted to melt flow. Weight distribution in large containers is controlled by the interaction between the melt strength curve and the parison programming profile. HS-5010 may exhibit a different shear history in the parison head, with a lower or higher die swell than the replaced grade, so the programmed die-gap curve should not be copied unchanged. Tooling clearance, mandrel geometry, and die land length are typically adjusted only after measuring the parison length sag at three hang times: 2 s, 5 s, and 8 s. This empirical approach is supported by ISO 11443 rheology data but is not replaced by it.

In production, the screw speed and back pressure may be adjusted to maintain melt temperature below 220 °C. Because HS-5010 is intended for blow moulding, screw geometries designed for HDPE with a barrier section and grooved feed throat can consume more torque than a smooth-bore extruder at the same output. The barrel temperatures should be verified with an insertion thermocouple rather than relying on machine PID displays; a deviation of 5 °C in the head zone can shift die swell enough to alter bottle weight by a measurable percentage. If the mould remains unchanged, the replacement may require cooling time adjustments because part solidification is governed by mould temperature and wall thickness, not solely by resin melt index.

From a chemical resistance standpoint, HDPE HS-5010 is considered resistant to many dilute acids, alkalis, and polar organic liquids, but it is not serviceable with strong oxidising acids such as concentrated nitric acid, or with aliphatic and aromatic hydrocarbons that plasticise the amorphous fraction and reduce yield stress. The extent of solvent interaction is usually assessed by immersion testing under ISO 175:2010 at 23 °C and 60 °C, followed by tensile testing under ISO 527-2 to quantify retained stress and elongation. Swelling of the surface can precede environmental stress cracking when the container is under constant strain at the threaded neck or pinch-off. In such cases, ESCR data alone is not sufficient because the constant load and notch geometry in ASTM D1693 may not reproduce the actual stress field of a sealed closure.

Thermal limits are similarly bounded. HDPE containers made from HS-5010 are generally limited to continuous service temperatures below 60 °C; intermittent excursions to 80 °C are sometimes acceptable for short filling cycles, but this must be validated in the filled state because internal pressure from vapour pressure can deform the shoulder. The Vicat softening point measured under ISO 306 does not define the upper service temperature; creep modulus and tensile strength retention at elevated temperature are better indicators. For hot-fill or transport in unvented closures, a thorough distribution test under ASTM D4169 truck or air transport profiles is required.

Metal-contact incompatibility should also be noted. Extended contact with copper or copper alloys at process temperature can accelerate oxidative degradation in polyolefins through metal-ion catalysis. Brass tooling components are generally not used in critical melt-stream locations for long campaigns. If a production line has bronze screen packs or copper-containing thermocouple sheaths, their condition should be inspected frequently; the onset of catalytic oxidation can be detected by a decrease in oxidative induction time under ISO 11357-6 and by yellowing or surface roughness on the extrudate. The grade selection remains subject to lot-specific manufacturer data and finished-ware qualification.