| HS Code | 446746 |
| Polymer Type | High Density Polyethylene |
| Density | 0.946 g/cm³ |
| Melt Flow Rate 190 C 2 16 Kg | 0.35 g/10 min |
| Melting Temperature | 131 °C |
| Vicat Softening Temperature | 124 °C |
| Brittleness Temperature | < -70 °C |
| Tensile Strength At Yield | 25 MPa |
| Tensile Strength At Break | 30 MPa |
| Elongation At Break | >600 % |
| Flexural Modulus | 1100 MPa |
| Notched Izod Impact Strength At 23 C | 100 J/m |
| Hardness Shore D | 65 |
| Environmental Stress Crack Resistance 10 Igepal F50 | >1000 h |
As an accredited Braskem HDPE HD4600U factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Braskem HDPE HD4600U is typically supplied in 25 kg polyethylene bags, stacked on pallets or shipped in bulk containers. |
| Container Loading (20′ FCL) | Braskem HDPE HD4600U high-density polyethylene resin loaded in a 20-foot FCL container, palletized in 25 kg bags, secured for export. |
| Shipping | Braskem HDPE HD4600U is a non-hazardous, solid polyethylene resin shipped as pellets in 25 kg bags, 1,000 kg supersacks, or bulk hopper trucks/railcars. Keep packaging dry, sealed, and away from heat, sunlight, and moisture. Handle carefully to prevent bag damage and pellet spills. No special DOT/IMDG/IATA hazard classification applies. |
| Storage | Store Braskem HDPE HD4600U resin in a cool, dry, well-ventilated area, away from direct sunlight, heat, sparks, and open flames. Keep original bags or containers tightly closed to prevent moisture, dust, and contamination. Avoid prolonged UV exposure, strong oxidizers, and physical damage. Maintain clean, dry handling conditions and follow the manufacturer’s SDS and local regulations. |
| Shelf Life | Shelf life for Braskem HDPE HD4600U is typically 2 years when stored in cool, dry, ventilated conditions away from direct sunlight. |
Parison sag and wall distribution in 120–220 L open-head drums and 1000 L intermediate bulk container liners are governed by three coupled variables: accumulator head tooling gap, parison programming stroke, and melt rheology. For Braskem HD4600U, the die gap on an accumulator head is set at 8–15 mm for a 500–900 mm parison, producing a swell ratio in the range of 25–45% depending on shear history and die land length. The blow-up ratio is held between 1.5:1 and 1.8:1; exceeding 1.8:1 produces non-uniform frozen-in orientation and reduces stack strength. Accumulator head tooling with a diverging die angle of 15–30° is preferred over parallel land tooling because it redistributes the weld line from the spider leg and reduces spur die lines that act as stress concentrators in drop impact. Melt temperature is limited to 205°C at the die exit; excursions to 220°C for more than 10 min initiate chain branching and increase the gel count observed on pin-hole testing of 3–5 mm walls. The extruder used in this application is typically a 90–120 mm grooved-feed single-screw extruder with an L/D of 30:1 to 36:1, fitted with a barrier screw and a mixing section. Output rates are limited by melt temperature rise rather than torque: a 120 mm extruder delivering 350–450 kg/h at 90–110 rpm can exceed the 205°C limit if the feed throat is not cooled to 40–60°C. After parison extrusion, pre-blow air at 0.05–0.2 MPa is introduced to avoid draw-down, followed by main blow at 0.6–0.9 MPa. The mould closing speed is set at 150–250 mm/s, and the pinch-off insert temperature is maintained at 10–20°C to freeze the weld before crack initiation. Cycle time for a 220 L open-head drum with a 3.5 mm minimum wall is in the range of 140–180 s; for a 1000 L IBC liner, cycle time extends to 240–360 s with post-cooling in the mould at 0.4–0.6 MPa internal air pressure.
In tight-head packaging lines configured for UN 1H1 jerrycans, Braskem HD4600U is processed at a nominal melt flow rate of 0.60 g/10 min (190°C/2.16 kg, ISO 1133-1:2022) and a density of 0.946 g/cm³ (ISO 1183-1). The grade’s high molecular weight, evidenced by a melt flow rate below 1.0 g/10 min, supplies the melt strength required for parison lengths exceeding 300 mm during the production of 20–30 L UN 1H1 tight-head jerrycans. Barrel temperatures are profiled at 170–205°C; die and head zones are kept between 190°C and 200°C to avoid excessive die swell while maintaining a homogeneous melt at the accumulator or reciprocating screw tip. Mould cooling water is supplied at 10–20°C; return water is not allowed to exceed 35°C because cooling-rate gradients across the pinch-off are the primary source of warpage and environmental stress crack initiation in subsequent UN drop tests. Blow air pressure is controlled at 0.6–0.8 MPa, with blow time between 30 s and 50 s depending on wall thickness; total cycle time for a 250 g jerrycan on a single-station shuttle is between 70 s and 120 s. Parison programming divides the extrusion stroke into 10–25 points, thinning the lower segment by 15–25% relative to the upper segment to compensate for draw-down. The finished package is normalized at 23±2°C and 50±5% RH for 40 h before testing. Compliance is established under UN Model Regulations Chapter 6.1, ADR 6.1.5, and IMDG Code P001; the internal hydrostatic test is conducted at 100–250 kPa for 30 min, followed by a drop test from 1.2–1.8 m after conditioning at -18°C for 24 h. Stack compression is maintained at ≥350 kg for 28 days at 40°C, and leakproofness is verified after the drop and stacking sequence. These procedures reflect production-scale quality control practice rather than laboratory-only validation, and the numerical limits are harmonized with the dangerous-goods packaging certification required for solvent, agrochemical, and intermediate liquid transport.
| Test | Standard | Condition | Typical lot value |
|---|---|---|---|
| Melt flow rate | ISO 1133-1:2022 | 190°C, 2.16 kg | 0.60 g/10 min |
| Density | ISO 1183-1 | 23°C | 0.946 g/cm³ |
| Environmental stress cracking | ASTM D1693 | 100% Igepal CO-630, Condition B | F50 > 600 h |
| Tensile yield | ASTM D638-14 | 50 mm/min | 26 MPa |
| Flexural modulus | ASTM D790-17 | 2 mm/min | 1100 MPa |
Multilayer barrier bottles for agricultural chemical concentrates are co-extruded with HD4600U as the structural and regrind-carrier layers because its ESCR performance under ASTM D1693 Condition B exceeds 600 h, reducing the risk of environmental stress cracking when exposed to emulsifiable concentrates and petroleum solvents. The six-layer structure is produced on a 3–6 layer continuous co-extrusion blow-moulding machine with separate barrier extruders for polyamide or EVOH and tie-layer extruders for maleic anhydride grafted polyethylene. A typical continuous layer distribution is shown in Table 2; the HDPE structural layers account for 70–75 wt% of the total bottle mass, while the barrier layer is held at 2–3 wt%, the tie layers at 2–4 wt%, and the recycled layer at 20–30 wt%. The HD4600U extruder is run at 190–200°C; the EVOH extruder is maintained at 190–210°C with a residence time below 10 min to avoid gel formation. Bottle mass for a 1 L agrochemical bottle is typically 45–55 g; wall thickness is controlled between 0.8 mm and 1.2 mm, with the barrier layer not less than 20 μm at the thinnest shoulder region. The product is tested for solvent permeation using ASTM D2684 or a gravimetric loss method at 40°C for 28 days, with pass criteria typically set at ≤1.5% weight loss for paraffinic solvents. Drop impact after 24 h conditioning at -18°C must not produce cracking at the pinch-off; the bottle is also subjected to a 50 kPa internal air pressure for 5 min to detect pinholes. Regulatory documentation includes REACH Annex XVII restrictions, EC No 1907/2006, and local agrochemical packaging approvals where the packaged formulation is classified under UN 4G or UN 1H1 with the appropriate marking.
| Layer sequence | Material function | Typical mass fraction | Thickness share |
|---|---|---|---|
| Outer skin | HD4600U virgin | 15–20% | 20–25% |
| Tie | MAH-grafted PE | 2–3% | 3–5% |
| Barrier | EVOH 32 mol% ethylene | 2–3% | 3–5% |
| Tie | MAH-grafted PE | 2–3% | 3–5% |
| Regrind core | HD4600U + multilayer regrind | 20–30% | 25–35% |
| Inner skin | HD4600U virgin | 30–40% | 30–40% |
Pinch-off geometry becomes the controlling variable in large open-head drums when the mould closes on a 3–5 mm parison wall at speeds above 200 mm/s. The flash pocket should allow 60–70% compression of the wall, leaving a weld land of 0.3–0.8 mm; overcompression beyond 70% causes excessive orientation and reduces weld strength by 30–50% under ASTM D638 tensile testing. The feed of the pinch-off insert is angled at 20–35° from the parting line to direct flash outward without thinning the corner; parallel inserts without relief pockets produce a cold slug that acts as a notch in drop tests at -18°C. Cooling water at 8–12°C to the pinch-off insert is maintained for 30–60 s before knock-out; premature ejection below 20 s produces post-mould warpage in the bottom pellet. Weld integrity is verified annually by sectioning the pinch-off zone and measuring residual wall thickness under ISO 2818; acceptable values are not less than 55% of the nominal sidewall thickness. For HD4600U, the notch-sensitive transition from ductile to brittle failure appears in laboratory Izod tests at about -20°C to -30°C, but the pinch-off weld can shift this transition to -10°C if the flash pocket is too narrow. Production-scale failure records from 220 L drum lines show that the bottom weld is the first crack site in UN drop testing at 1.2 m after -18°C conditioning when the pinch-off land exceeds 1.0 mm; laboratories should therefore set the land to 0.4–0.6 mm for balanced weld strength and flash removal.
Post-industrial regrind of HD4600U containers is reintroduced into non-food packaging only after the melt flow rate has been verified at 0.60 ± 0.10 g/10 min under ISO 1133-1:2022; batch-to-batch deviation beyond ±0.10 g/10 min indicates oxidative chain scission from repeated heat history and requires a reduction of regrind fraction to below 15 wt%. The blending ratio in closed-loop agrochemical container lines is kept at 20–30 wt% regrind when a continuous gravimetric blender feeds the main extruder; higher fractions up to 50 wt% are tolerated only in thick-wall drums with minimum wall thickness above 3 mm and when the regrind is melt-filtered through a 60–80 mesh screen pack upstream of the die head. The primary limitation is not tensile yield, which remains within 10% of virgin resin at 30 wt% regrind, but environmental stress crack resistance; ASTM D1693 Condition B F50 values can fall from 600 h to below 200 h when gel particles and degraded low-molecular-weight fractions promote crack nucleation. Extruder barrel temperatures for recycled blends are lowered by 5–10°C relative to virgin settings to counteract the lower melt viscosity of reused material; head pressure is monitored at 15–25 MPa and a drop below 12 MPa at constant screw speed indicates an excessive low-viscosity fraction. The terminal products are industrial pails, crates, and inner liners where food-contact approval is not required; compliance is governed by REACH EC No 1907/2006 and, for packaging in short service life, EN 15343 traceability requirements.
Intermodal IBC liners blow-moulded from HD4600U are used for liquid ingredients shipped under ISO 1496-3 tank container testing conditions where the liner must survive rail and road vibration at -20°C without crack propagation from the top valve boss or bottom discharge port. The liner wall is specified at 3.0–4.0 mm, with a top-lifting collar thickness of 6–8 mm and a bottom valve pad of 8–10 mm; injection-moulded inserts are not used because the differential shrink rate creates stress risers. The blow-moulding process uses a 120 mm accumulator-head machine with parison programming that thickens the bottom section by 30–40% relative to the sidewall. Mold temperature is set to 8–12°C to maximize crystallinity near the pinch-off; but mould temperatures below 8°C create frost build-up on cooling lines and reduce surface finish without meaningful impact gain. After moulding, liners are annealed at 80°C for 2 h to relax frozen-in orientation from the accumulator head; this step raises the ASTM D1693 F50 value by 20–40% in lot trials. Ultrasonic thickness mapping along 16–24 circumferential points per level is used to reject liners with wall variation greater than ±15% of nominal. Transport compliance is validated by vibration testing under ISO 2247 at 2–5 Hz for 60 min, followed by a 1.2 m cold drop at -18°C. Published data for this specific configuration is limited beyond these standard test conditions, but production records show failures concentrate at the bottom pinch-off and at the discharge port weld when wall thickness falls below 2.5 mm.
Competitive Braskem HDPE HD4600U prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8618136850665 or mail to admin@ascent-chem.com.
We will respond to you as soon as possible.
Tel: +8618136850665
Email: admin@ascent-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Braskem HD4600U is a high-molecular-weight high-density polyethylene specified for extrusion blow moulding and heavy-gauge sheet. Its melt flow rate, measured under ASTM D1238-20 at 190 °C/2.16 kg, is 0.45 g/10 min; density, determined by ISO 1183-1:2019, is 0.946 g/cm³. The melt flow rate places the grade in the high-viscosity segment of HDPE, where parison melt strength and environmental stress crack resistance dominate over injection-moulding flowability. The product is therefore specified for large blow-moulded containers, including 200 L tight-head drums, intermediate bulk container liners, and industrial jerrycans for aggressive liquid media.
Mechanical property values from published technical literature for this resin fall within the following ranges: tensile yield stress 25–28 MPa under ASTM D638-14 at 50 mm/min; elongation at break greater than 600%; flexural modulus 1000–1200 MPa under ASTM D790-17; and notched Izod impact resistance that frequently produces no-break results at 23 °C. Shore D hardness is typically 64–66. These short-term properties derive from the semicrystalline morphology and are less discriminating than environmental stress crack resistance when selecting a drum-grade resin.
HD4600U exhibits pronounced shear thinning in capillary and oscillatory shear. The 0.45 g/10 min melt flow rate is a low-shear index; during blow moulding, the resin passes through annular dies at wall shear rates commonly between 100 s⁻¹ and 1000 s⁻¹, where apparent viscosity is considerably lower than the low-shear value. This combination permits acceptable die head pressure while retaining high zero-shear viscosity for parison hang time. For high-molecular-weight HDPE grades of this MFR, parallel-plate oscillatory measurements at 190 °C typically show complex viscosities from 1 × 10⁵ Pa·s to 3 × 10⁵ Pa·s at 0.1 rad/s; published data for this specific grade is limited, but the range is consistent with observed melt strength. Capillary rheometry values are approximately 800–1200 Pa·s at 100 s⁻¹ and 200–300 Pa·s at 1000 s⁻¹, following conventional HDPE shear thinning.
The density of 0.946 g/cm³ indicates limited comonomer incorporation relative to linear-low-density polyethylene but sufficient short-chain branching to disrupt crystallinity and improve slow crack growth resistance. Crystallinity determined by differential scanning calorimetry according to ISO 11357-3:2018 is typically 60–70% for resins in this density range. Die swell in blow moulding grades of this molecular weight is moderate, with reported values of 1.4–1.8 depending on die land length and shear history. This swell contributes to wall thickness distribution only when accumulator-head tooling and parison programming are matched to the resin’s memory effect.
Compared with injection-moulding HDPE grades with melt flow rates above 5 g/10 min, HD4600U has far greater extensional viscosity and sag resistance. Compared with thin-wall bottle grades, it is designed for slower hang times and thicker sections. The high-molecular-weight tail also lowers the melt fracture threshold; die land shear rates above 500 s⁻¹ may induce sharkskin or helical melt fracture depending on tooling diameter and melt temperature. The Cox-Merz approximation is broadly applicable to this grade for correlating complex viscosity with steady shear viscosity in process simulations.
Accumulator-head blow moulding of 200 L drums using HD4600U is typically carried out on single-screw extruders with screw diameters of 60–90 mm and length-to-diameter ratios of 24:1 to 30:1. Barrel temperature profiles reported from production lines range from 170 °C in the feed zone to 220 °C at the head, with die temperatures maintained between 190 °C and 210 °C. Melt temperatures below 180 °C increase shear heating and risk thermally induced gel formation; melt temperatures above 230 °C accelerate oxidative degradation, reduce molecular weight, and compromise environmental stress crack resistance. For continuous-extrusion shuttle machines, the same melt temperature window applies, but parison hang time is shorter and parison programming velocity must be adjusted to avoid draw-down. Die gaps are normally set at 1.5–2.5 mm, and blow pressures of 0.6–0.9 MPa are common for large containers. Mould temperatures of 10–20 °C shorten cycle time, while cooling times for 200 L drums may extend from 180 s to 240 s depending on wall thickness and ambient conditions. Published production-scale data for this specific configuration is limited, but these ranges are representative of industrial practice.
In 25 L jerrycan production on shuttle blow moulding machines with 60 mm extruders, HD4600U is processed at melt temperatures between 185 °C and 210 °C. The high melt strength permits a parison length-to-diameter ratio that would cause draw-down in a 0.7 g/10 min grade. Weld-line integrity at the pinch-off is influenced by melt temperature and mould closing speed; insufficient closing force can create a weak pinch-off that fails in stack-loading. Mould pinch-off inserts with a 0.5–1.0 mm land and a 30–45° included angle are commonly used to produce a strong weld. This application illustrates the grade’s advantage over lower-viscosity HDPE but also the need for tooling control.
In heavy-gauge sheet extrusion, HD4600U requires a flat die with a 2–4 mm lip gap and a three-roll polishing stack maintained at 70–90 °C. Compared with medium-molecular-weight HDPE sheet grades, the material exhibits higher backpressure and lower melt pumping efficiency, so screw speed and barrel temperatures should be adjusted to prevent excessive residence time. Sheet thickness above 8 mm benefits from the grade’s high melt strength, but cooling time increases because the thicker section retains heat.
Environmental stress crack resistance is the failure mechanism by which a stressed polyethylene part develops brittle cracking in the presence of a surface-active agent, even below the short-term yield point. For high-molecular-weight HDPE drum grades, ESCR tests are usually performed according to ASTM D1693-15 in 100% Igepal CO-630 at 50 °C. Under these conditions, HD4600U-type resins are selected for F50 values above 600 h, and some production lots exceed 1000 h. The test method has known scatter because specimen thickness, notch depth, temperature, and surfactant concentration all influence time to failure. The value is therefore a comparative ranking rather than an absolute service life.
The structural origin of ESCR in HDPE is the density of tie molecules connecting lamellar crystals across amorphous regions. Slow crack growth resistance improves with higher molecular weight, broader molecular weight distribution, and limited comonomer incorporation. HD4600U balances these variables to yield ESCR values substantially higher than general-purpose HDPE blow moulding grades. Where an aggressive surfactant or solvent is packaged, the difference between 50 h and 600 h under ASTM D1693-15 can determine whether a drum survives a transport cycle without environmental cracking. ESCR does not imply chemical resistance to all fluids; strong oxidizers, aromatic hydrocarbons, and chlorinated solvents require compatibility testing under service conditions.
The contrast between HD4600U and high-flow HDPE injection grades is not limited to melt viscosity. High-flow grades with melt flow rates above 20 g/10 min have much lower tie-molecule density, lower ESCR, and higher crystallinity due to lower molecular weight. They are unsuitable for blow moulding because parison sag occurs before mould closing. Conversely, pipe-grade HDPE often has a broader bimodal molecular weight distribution and higher slow crack growth resistance but may be more difficult to process in blow moulding due to higher die swell and surface roughness. HD4600U is therefore positioned for thick-wall, large-part blow moulding rather than for thin-wall bottles or injection moulding.
Comparative property data between HD4600U and a conventional HDPE blow moulding grade with a melt flow rate of 0.30 g/10 min are presented in Table 1. The values are typical ranges from published technical literature, not batch guarantees. In particular, ESCR differences can exceed the magnitude of short-term mechanical property differences, which is why material substitution based only on density and MFR is insufficient for dangerous-goods packaging.
| Property | Test method | HD4600U typical | General-purpose HDPE blow moulding typical |
|---|---|---|---|
| Melt flow rate | ASTM D1238-20, 190 °C/2.16 kg | 0.45 g/10 min | 0.30 g/10 min |
| Density | ISO 1183-1:2019 | 0.946 g/cm³ | 0.952 g/cm³ |
| Tensile yield stress | ASTM D638-14 | 25–28 MPa | 27–30 MPa |
| Elongation at break | ASTM D638-14 | >600% | >400% |
| Flexural modulus | ASTM D790-17 | 1000–1200 MPa | 1200–1400 MPa |
| ESCR, 100% Igepal F50 | ASTM D1693-15 | >600 h | 20–100 h |
Regrind incorporation alters the melt rheology and mechanical performance of HD4600U. In production-scale drum blow moulding, up to 30 wt% clean, dry regrind is commonly used without significant loss of ESCR, provided that the regrind is not degraded by multiple heat histories. Above 30 wt%, molecular weight reduction from repeated extrusion becomes measurable: melt flow rate increases by approximately 0.05–0.10 g/10 min per additional heat history, die swell decreases slightly, and parison sag in long accumulator-head strokes becomes more difficult to control. If regrind content reaches 50 wt%, ESCR can fall below 300 h even when the virgin resin initially exceeded 600 h. The lower-viscosity blend fills the accumulator faster and accelerates parison draw-down, narrowing the usable processing window.
Moisture is generally not a primary concern for HDPE, but condensation on cold regrind from outdoor storage can generate surface defects and voids. Regrind should be dry and free of contamination from polypropylene closures, paper labels, and metal residues. Polypropylene contamination at 5 wt% is sufficient to produce visible delamination in the pinch-off region because the two polymers are immiscible and have different melt elasticity. For dangerous-goods packaging, a minimum virgin-to-regrind ratio should be specified in the quality plan, and the ESCR of the mixed feedstock should be re-verified by ASTM D1693-15 rather than inferred from the virgin resin certificate.
For food-contact and pharmaceutical packaging, HD4600U may be evaluated under FDA 21 CFR 177.1520(c) for olefin polymers and under EU Regulation 10/2011 with subsequent amendments, provided the finished article is tested for overall migration and specific migration limits according to the intended food type and contact time. The resin is subject to registration under REACH Regulation EC 1907/2006 and must meet RoHS Directive 2011/65/EU restrictions for hazardous substances when used in electrical and electronic equipment enclosures. These regulatory references are not self-certifying; converters are responsible for verifying that additives, colourants, and process aids used in the final compound do not compromise compliance.
| Regulation/standard | Typical assessment basis | Relevant article or clause |
|---|---|---|
| FDA 21 CFR 177.1520 | Olefin polymer for food contact | Paragraph (c), items 2.1 and 3.1 |
| EU 10/2011 | Plastic materials intended to contact food | Annex I and Article 17 |
| REACH 1907/2006 | Registration, evaluation, authorisation | Title II, Chapter 1 |
| RoHS 2011/65/EU | Lead, mercury, cadmium, hexavalent chromium, PBB, PBDE | Annex II, maximum concentration 0.1 wt% per homogeneous material |
At melt temperatures above 230 °C or with residence times exceeding 15 min in the accumulator head, chain scission generates low-molecular-weight fractions that increase odour, reduce ESCR, and may form gel particles in the parison. The grade should not be purged with polyvinyl chloride or acetal resins because thermal decomposition products may corrode tooling and contaminate the melt stream. For outdoor applications, if the resin is supplied without a sufficient UV stabiliser package, ultraviolet exposure may cause embrittlement within 12–24 months unless carbon black or a separate UV masterbatch is added. The suffix in the grade designation does not by itself establish the additive package, and the supplier’s certificate should be checked. These limits define the operational boundary for HD4600U and distinguish it from lower-viscosity, higher-flow HDPE grades that are unsuitable for large-part blow moulding.
