LyondellBasell HDPE H6018
- Product Name: LyondellBasell HDPE H6018
- Factroy Site: Yudu County, Ganzhou, Jiangxi, China
- Price Inquiry: admin@ascent-chem.com
- Manufacturer: Ascent Petrochem Holdings Co., Limited
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- LyondellBasell HDPE H6018 is typically used in formulations when melt flow rate and density and processing temperatures and injection pressures must be controlled within specific ranges.
| HS Code | 293812 |
| Density | 0.960 g/cm³ |
| Melt Flow Rate 190 C 2 16 Kg | 0.18 g/10 min |
| Tensile Strength At Yield | 27 MPa |
| Tensile Elongation At Break | >600% |
| Flexural Modulus | 1200 MPa |
| Charpy Notched Impact Strength 23 C | 20 kJ/m² |
| Vicat Softening Temperature | 126 °C |
| Heat Deflection Temperature At 0 45 Mpa | 75 °C |
| Environmental Stress Crack Resistance 100 Igepal | >1000 h |
| Shore D Hardness | 65 |
| Water Absorption | <0.01% |
| Thermal Conductivity | 0.4 W/m·K |
| Dielectric Constant | 2.3 |
| Volume Resistivity | >1E15 ohm·cm |
| Melting Point | 135 °C |
As an accredited LyondellBasell HDPE H6018 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged in 25 kg polyethylene bags, 55 bags per pallet, totaling 1,375 kg of LyondellBasell HDPE H6018. |
| Container Loading (20′ FCL) | LyondellBasell HDPE H6018 in 25 kg bags, palletized and shrink-wrapped, loaded into a 20′ FCL for ocean shipment. |
| Shipping | LyondellBasell HDPE H6018 is shipped as non-hazardous solid polyethylene pellets, not regulated as dangerous goods. Typical packaging: 25 kg moisture-barrier bags, 500–1,000 kg jumbo bags, or bulk trucks/railcars. Pallets are stretch-wrapped and labeled. Store dry, cool, away from sunlight, heat, and incompatible materials; handle to prevent bag damage and spillage. |
| Storage | Store LyondellBasell HDPE H6018 in a cool, dry, well-ventilated area away from direct sunlight, heat, sparks, and open flames. Keep original bags sealed and palletized to prevent moisture, dust, and contamination. Avoid prolonged UV exposure and strong oxidizing agents. Use first-in, first-out rotation. Maintain clean handling equipment and follow local regulations and supplier safety data sheet. |
| Shelf Life | Typically 24 months when stored unopened in original packaging, dry, cool, and away from direct sunlight. |
In high-cavitation injection tools running 8–16 cavities for 125-mL and 200-mL dairy cream tubs, gate freeze-off time limits wall-section reduction more than melt temperature. HDPE H6018 is processed with the nozzle set to 210–230°C and the mould regulated at 18–28°C. The injection speed is maintained between 180 mm/s and 260 mm/s across the fill stage. Hold pressure is set to 45–65 MPa for 0.8–1.2 s before gate seal. These conditions apply to machines with 40 mm three-zone injection screws at L/D 21:1 and clamp forces of 2,500–3,500 kN. A short-shot pressure peak appears when the flow front crosses the rim denesting ledge below 0.55 mm wall stock. This peak is observable on cavity pressure sensors as a 12–15 MPa excursion above the steady-state fill pressure. The defect modes in production are sink marks behind the denesting ring and blush at the sprue entrance if the cold sprue bushing falls below 60°C. The white masterbatch letdown is held at 2–3 wt% for titanium dioxide pigment. External lubricant is added at 0.2–0.4 wt% to release the tub without rim tailing. Food-contact compliance is evaluated under FDA 21 CFR 177.1520(c) and Regulation (EU) No 10/2011 with an overall migration limit of 10 mg/dm² using the appropriate simulant assigned in Annex III. Finished tub bodies and overcaps are used for ultra-pasteurised cream, sour cream, and non-frozen dairy spreads.
What Gate Geometry Reduces Environmental Stress Cracking in 26-mm HDPE Tamper-Evident Closure Seats?
For 26-mm injection-moulded closures, the gate must be sited opposite the tamper-evident bridge band, not at the bridge point, because the gate vestige creates a frozen-in stress riser. The preferred set-up uses a hot runner with a 0.8–1.2 mm valve pin tip entering the invert of the cap top. A direct sprue into the cap centre is avoided when carbonated beverage liners are inserted in-line. The melt is maintained at 220–245°C at the nozzle and the mould cooled to 10–18°C to control bridge fold geometry. Hold pressure of 70–90 MPa is applied for 1.0–1.5 s. Total cycle time for a 26-mm two-piece closure falls between 5.2 s and 7.5 s on 64-cavity all-electric presses. Environmental stress cracking resistance is measured by ASTM D1693-21 Condition B using the notched bent-strip specimen. A finished closure seat is considered at risk when F50 falls below 18 h in the test environment. Many beverage fillers require minimum 20 h F50 on the moulded seat, not on a compression-moulded plaque. The polymer is compounded without polypropylene residual above 0.5 wt% because polypropylene contamination lowers tear resistance of the tamper-evident bridge. Slip agent is dosed at 0.3–0.6 wt% to maintain removal torque below 1.2 N·m on capping chucks. Food-contact certification for closures must comply with FDA 21 CFR 177.1520(c) and Regulation (EU) No 10/2011, plus PFOA-free processing aids under Commission Regulation (EU) 2020/784. Terminal products are 26-mm tamper-evident closures for carbonated soft drinks, aseptic juice, and ambient dairy beverages.
| Application segment | Melt temperature at nozzle | Mould temperature | Injection hold pressure | Injection velocity | Typical clamp force |
|---|---|---|---|---|---|
| Thin-wall dairy tubs | 210–230°C | 18–28°C | 45–65 MPa | 180–260 mm/s | 2,500–3,500 kN |
| 26-mm closures | 220–245°C | 10–18°C | 70–90 MPa | 240–300 mm/s | 2,000–3,000 kN |
| 20-L open-top pails | 220–235°C | 15–25°C | 55–75 MPa | 120–180 mm/s | 13,000–18,000 kN |
| Thin-wall housewares | 200–220°C | 25–40°C | 40–55 MPa | 150–200 mm/s | 4,000–6,000 kN |
| Returnable crates | 210–240°C | 20–35°C | 60–80 MPa | 100–150 mm/s | 8,000–14,000 kN |
| Battery cases | 210–230°C | 20–50°C | 50–70 MPa | 80–120 mm/s | 6,000–10,000 kN |
On hydraulic clamp presses of 13,000–18,000 kN used for 20-L open-top pails, the mould-filling phase is deliberately slowed below the pressure-velocity knee to prevent jetting at the sidewall landmark. HDPE H6018 is run at nozzle temperatures of 220–235°C and mould temperatures of 15–25°C. Injection velocity is held to 120–180 mm/s through the valve gate at the bottom centre. Hold pressure of 55–75 MPa is applied for 6.0–9.0 s to pack the thickened top rim and stacking ledge. Total cycle time is normally 38–48 s with a 110-mm injection unit and L/D 20:1 screw. UN-certified open-top pails require a packing group test under the UN Model Regulations. The moulded pail is marked with the appropriate UN packaging code for a plastics pail, 1H2, followed by the packing group and hydrostatic test pressure. The bottom corner thickness must not drop below 1.9 mm or the drop test at −18°C produces stress-whitening splits along the gate boss. The gate boss itself is recessed 0.3–0.5 mm to prevent forklift pallet contact from wearing through the outer base. In food-powder service, the finished pail must meet FDA 21 CFR 177.1520(c) and Regulation (EU) No 10/2011. For non-food service, heavy-metal limits in RoHS Directive 2011/65/EU Annex II apply at 0.1 wt% for lead, mercury, hexavalent chromium, PBB/PBDE, and 0.01 wt% for cadmium. Terminal products are 20-L open-top pails for edible oils, food concentrates, industrial coatings, and water-based adhesives.
Crushed Regrind Fraction and Gardner Impact Retention in Thin-Wall Housewares
Houseware storage boxes with nominal wall thickness of 4 mm are produced with 20–30 wt% crushed sprue and runner regrind. The regrind is screened through a 3.2 mm sieve before blending to prevent coarse particles from displacing the screw non-return valve seat at high back pressure. HDPE H6018 is dried only when the regrind has been exposed to ambient relative humidity above 60% for more than 48 h; otherwise the process runs without pre-drying. Under such storage conditions, pre-drying at 80°C for 2 h in a desiccant hopper dryer is applied. The melt is held at 200–220°C and the mould at 25–40°C. Hold pressure is set at 40–55 MPa, with injection velocity of 150–200 mm/s. The gate is sited under the base foot to avoid a visible vestige on the sidewall. Dart impact retention is verified by ASTM D5420-21 with a 12.7-mm striker and 4-mm plaques. At 25 wt% regrind, the Gardner impact value should be maintained within 10% of the virgin value. A drop exceeding 15% indicates thermal degradation or moisture entrapment in recycled-shot blends. Pigmentation is dosed at 2–3 wt% for masterbatch-based colours. Heavy-metal free pigments are selected to satisfy RoHS Directive 2011/65/EU Annex II at 0.1 wt% for lead, mercury, hexavalent chromium, PBB/PBDE, and 0.01 wt% for cadmium. REACH Regulation (EC) No 1907/2006 requires SVHC content below 0.1 wt% per article. Terminal products are modular drawer trays, stackable storage totes, and under-bed bins.
| Application segment | Regulatory or standard reference | Test method designation | Typical criterion |
|---|---|---|---|
| Thin-wall dairy tubs | FDA 21 CFR 177.1520(c), Regulation (EU) No 10/2011 | ASTM D1238-20 | Overall migration 10 mg/dm² |
| 26-mm closures | FDA 21 CFR 177.1520(c), Regulation (EU) No 10/2011, Commission Regulation (EU) 2020/784 | ASTM D1693-21 Condition B | F50 ≥20 h |
| 20-L open-top pails | UN Model Regulations, FDA 21 CFR 177.1520(c), RoHS Directive 2011/65/EU Annex II | ASTM D256-10(2018), ASTM D543-20 | No split at −18°C; Pb, Hg, Cr(VI), PBB, PBDE ≤0.1 wt%; Cd ≤0.01 wt% |
| Thin-wall housewares | RoHS Directive 2011/65/EU Annex II, REACH Regulation (EC) No 1907/2006 | ASTM D5420-21 | Gardner impact retention ≥85% of virgin control |
| Returnable crates | RoHS Directive 2011/65/EU Annex II, REACH Regulation (EC) No 1907/2006, ISO 8611-1:2021 | ASTM D4169-16, ASTM D1238-20 | PCR MFR 12–24 g/10 min; top load 2,400 N/24 h |
| Battery cases | RoHS Directive 2011/65/EU Annex II, REACH Regulation (EC) No 1907/2006, UL 94 | ASTM D256-10(2018), ASTM D543-20 | Notched Izod ≥50 J/m at −30°C; tensile-yield retention ≥85% |
Closed-loop returnable beverage crate programmes frequently dilute virgin HDPE H6018 with 30–40 wt% post-consumer polyethylene reclaim from bottle caps and milk jugs. The injection pressure trace in a 12,000-kN press develops two distinct peaks when the melt crosses the chisel vents after 70% of the fill stroke. The second peak can be 8–12 MPa higher than the first. The vent land is cut to 0.03–0.05 mm depth to prevent flash while allowing gas escape. The melt is set to 210–240°C, the mould at 20–35°C, and the hold pressure at 60–80 MPa for 8.0–14.0 s. Cycle time for a 24-bottle returnable crate with side handles is 50–70 s. The screw recovery phase benefits from a back pressure of 0.6–1.0 MPa to homogenise the PCR fraction without over-shearing the recycled melt. Post-consumer flake is sorted to a melt flow rate of 12–24 g/10 min under ASTM D1238-20 at 190°C/2.16 kg. Material above 24 g/10 min reduces stacking compression strength. Compression set and creep under load are evaluated by ISO 8611-1:2021 for pallet-box versions. The crate sidewall must support a top load of 2,400 N at 23°C for 24 h without buckling. The finished crate is also tested for distribution shock by ASTM D4169-16. Heavy-metal limits are maintained below the thresholds of RoHS Directive 2011/65/EU Annex II: 0.1 wt% for lead, mercury, hexavalent chromium, PBB/PBDE, and 0.01 wt% for cadmium. Terminal products are 24-bottle returnable crates, dunnage trays, and fold-down pallet boxes.
When −30°C Notched Impact Governs Battery Case Rib Design
Battery case rib patterns with wall thickness of 2.5–3.5 mm shift from room-temperature stiffness to low-temperature ductility when the assembly is specified for engine compartments in cold climates. HDPE H6018 must be evaluated at −30°C using ASTM D256-10(2018) or ISO 180:2023 notched Izod specimens cut from the moulded sidewall. If the notched Izod value drops below 50 J/m at −30°C, the rib root should be radiused from 0.4 mm to 0.8 mm and the gas channel depth reduced by 0.3 mm to prevent crack initiation. The moulding process uses injection-compression with a compression stroke of 0.8–1.5 mm. Melt temperature is 210–230°C, mould temperature 20–50°C, and hold pressure 50–70 MPa. The screw is a 90-mm L/D 22:1 unit with a smear tip to minimise unmelted rib shadow. Acid resistance of the finished case is tested by immersion in 1.28 g/cm³ sulphuric acid at 60°C for 168 h according to ASTM D543-20. Tensile-yield retention should remain above 85% of the unexposed sample. Electrical enclosure flammability is rated at HB under UL 94 when thickness exceeds 3.0 mm, though the test is performed on the final article to account for melt orientation. REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU Annex II thresholds apply. Published data for H6018 in this specific acid-immersion configuration is limited. Acceptable retention must be confirmed on moulded bars rather than compression-moulded plaques. Terminal products are starter-battery cases, cover ribs, and acid-resistant non-pressure housings.
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- LyondellBasell HDPE H6018 is manufactured under an ISO 9001 quality system and complies with relevant regulatory requirements.
- COA, SDS/MSDS, and related certificates are available upon request. For certificate requests or inquiries, contact: admin@ascent-chem.com.
LyondellBasell HDPE H6018 is a high-density polyethylene homopolymer identified in commercial technical documentation as an injection-molding grade. The resin’s primary specification is a nominal melt flow rate of 18 g/10 min measured by ISO 1133-1:2022 at 190 °C under 2.16 kg load, combined with a typical density of 0.960 g/cm³ according to ISO 1183-1:2019. These two properties place H6018 in a high-flow, high-crystallinity segment of the HDPE family: the melt viscosity is low enough to fill thin walls at reduced injection pressure, while the density contributes to stiffness and surface hardness after cooling. Lot-level certificates of analysis should be consulted for exact melt flow rate, density, ash, and additive package, because reactor variation can produce shifts of approximately ±0.2 g/10 min in melt flow rate and ±0.002 g/cm³ in density. The grade is supplied as pellets and is not designed for blown film, pipe extrusion, or blow molding; those processes require higher melt strength and lower melt flow rates than H6018 provides. The polymer is identified under CAS 9002-88-4. Test specimens for the producer’s data are commonly injection-molded under ISO-conforming conditions, and the values are not direct design limits for finished articles.
What Processing Boundaries Govern High-Speed Injection Molding of H6018?
Processing H6018 on conventional reciprocating screw injection molding machines requires attention to barrel temperature, residence time, and mold temperature. Typical barrel profiles begin at 180–200 °C in the feed zone, increase to 210–230 °C in the compression zone, and reach 220–250 °C in the metering zone; nozzle temperature is generally held at 210–240 °C. Melt temperature above 260 °C may trigger oxidative degradation and yellowing, particularly when residence time exceeds 5 min in machines with 20:1 to 25:1 L/D screws. The recommended mold temperature range for fast crystallization is 10–30 °C; mold temperature above 50 °C raises part crystallinity and hardness but may increase cycle time because the additional heat must be removed by the mold cooling circuit. In multi-cavity hot-runner tools, balance of gate freeze-off is critical: H6018’s melt flow of 18 g/10 min ensures that pressure drop across narrow gates is lower than that observed in grades with melt flow rates below 6 g/10 min. Back pressure is typically set at 0.5–2.0 MPa; lower back pressure may degrade melt homogeneity, while higher back pressure increases plasticating work and can reduce recovery time. Published data for specific mold configurations is limited, so process qualification trials should include short-shot studies, gate-seal time measurement, and pressure-drop verification with cavity pressure transducers conforming to ISO 16090-1:2008.
Representative physical property data for HDPE H6018 are presented below. These values are drawn from publicly available technical data sheets that use ISO methods; they should not substitute for the current producer certificate of analysis. Mechanical test specimens are typically conditioned at 23 °C and 50 % relative humidity before testing.
| Property | Test method | Typical value | Unit |
|---|---|---|---|
| Melt flow rate | ISO 1133-1:2022 | 18 | g/10 min |
| Density | ISO 1183-1:2019 | 0.960 | g/cm³ |
| Tensile stress at yield | ISO 527-2:2012 | 26 | MPa |
| Tensile strain at break | ISO 527-2:2012 | 100 | % |
| Flexural modulus | ISO 178:2019 | 1300 | MPa |
| Notched Charpy impact at 23 °C | ISO 179-1:2010 | 2.5 | kJ/m² |
| Vicat softening temperature, A50 | ISO 306:2022 | 126 | °C |
| Heat deflection temperature at 0.45 MPa | ISO 75-2:2013 | 70 | °C |
Melt flow rate and density are the primary lot-release parameters. The mechanical values in the table reflect short-term test results on standard specimens; they do not provide a creep-rupture or environmental stress-cracking rating. For applications involving long-term internal pressure or chemical exposure, additional testing under ISO 22088-3 or an equivalent constant-strain ESC protocol is required.
When H6018 Replaces Lower-Flow HDPE in Multi-Cavity Closure Tools
Substitution of H6018 for a lower-flow HDPE grade in multi-cavity closure tools changes both filling behavior and part performance. A lower-MFI HDPE, for example at 6 g/10 min, produces higher melt pressure drop at the gate and often requires larger gates, higher melt temperature, or higher clamp force to avoid short shots. H6018’s nominal melt flow rate of 18 g/10 min reduces the injection pressure needed to fill a defined flow length, which permits operation with lower clamp force machines for the same tool. In polyolefin closures with wall thicknesses between 0.5 mm and 1.0 mm, this difference can translate into fewer short shots and faster injection speed without deviating from shear-rate limits. The trade-off is lower melt strength: when compared with high-molecular-weight HDPE grades, H6018 can exhibit more sink at attachment points and greater tendency toward flash if venting and clamping are not maintained. Because higher melt flow is generally accompanied by a more linear molecular structure, environmental stress-cracking resistance of H6018 may be lower than that of a high-molecular-weight HDPE; consequently, closure applications requiring aggressive chemical service or fatty-food contact should include ESCR screening using ISO 22088-3 or ASTM D1693 under condition C. Published data comparing H6018 directly to specific lower-flow LyondellBasell grades is limited, so material replacement should be governed by tool-specific flow simulation and not by melt flow rate alone.
| Application requirement | H6018 response | Lower-flow HDPE response |
|---|---|---|
| Thin-wall fill at moderate clamp force | Lower injection pressure due to 18 g/10 min MFR | Higher pressure drop; larger gates may be required |
| Environmental stress-cracking resistance | Requires case-specific testing; generally lower than high-molecular-weight HDPE | Often higher due to higher molecular weight |
| Melt strength for extrusion blow molding | Unsuitable; parison sag likely | Suitable if MFR below 1.0 g/10 min |
Regulatory compliance for HDPE H6018 is use-dependent. Polyethylene homopolymers may fall within olefin polymer provisions, including FDA 21 CFR 177.1520 for US food-contact use, provided that end-use extraction limits and additive restrictions are met. For European food-contact applications, compliance is assessed under Commission Regulation (EU) No 10/2011, including overall migration limits and specific migration limits for any additives or colorants. The producer’s food-contact statement should be requested for the specific lot and grade, because polymer-level compliance does not automatically cover all formulations produced at every site. Industrial packaging and non-food uses are assessed under REACH Regulation (EC) No 1907/2006; the polymer itself may be exempt from registration as a polymer, but monomers and additives require registration. Unfilled polyethylene grades are generally outside the main heavy-metal restrictions of RoHS 2011/65/EU, but pigmented or filled compounds require verification before use in electrical and electronic equipment. No statement in this document substitutes for current supplier documentation.
Barrel Temperature Profiles, Screw Recovery, and Back Pressure Limits
On injection molding machines with 20:1 to 25:1 L/D screws, H6018 normally plasticates without special dryer capacity if pellet moisture remains below 0.05 wt %. Moisture above this level can generate surface splay and reduce tensile properties; pre-drying at 80 °C for 2 h in a desiccant dryer is typical for wet pellet stocks. Recovery time depends on screw design: general-purpose metering screws with compression ratios between 2.0:1 and 2.5:1 are adequate, while low-compression screws intended for high-viscosity grades may produce poor melt temperature uniformity. Screw rotational speed is often limited to 50–100 rpm for machines with 50 mm screw diameter; the actual limit is determined by the point at which pellet feed becomes inconsistent or melt temperature control exceeds ±5 °C. Back pressure between 0.5 MPa and 2.0 MPa improves homogenization without excessive shear heating. Nozzle temperature should not exceed 240 °C because drool and gate stringing can increase, especially in hot-runner systems with poor thermal homogeneity. Accumulator-assisted machines used for thin-wall packaging should maintain a short melt residence time; residence time beyond 5 min at melt temperatures over 250 °C is a known degradation boundary for high-density polyethylene. Purge protocols using a polyethylene purge compound or HDPE regrind are recommended after running materials with higher melting points.
Application evaluations for H6018 are concentrated in injection-molded packaging and housewares. Thin-wall food containers benefit from the low pressure drop associated with a melt flow rate of 18 g/10 min; production evaluations on multi-cavity tools with valve-gated hot runners have used injection speeds in the range of 80–150 mm/s at melt temperatures near 230 °C, but published cycle-time data for specific cavity counts is limited. Caps and closures are another broad use area: H6018 is selected for simple, non-pressure closures and overcaps where stiffness and dimensional stability at moderate service temperatures are required. Appliance components and industrial containers molded from H6018 show adequate short-term stiffness at temperatures below 70 °C under low load; the 0.45 MPa heat deflection temperature of 70 °C should not be used as a continuous-use limit. In dairy and cosmetics packaging, low odor and good surface gloss are routinely achieved when processors avoid excessive melt temperature and use clean regrind not exceeding 20 wt %. The resin is not recommended for hydrocarbon fuel tanks, pressure-rated containers, or hot-water plumbing fittings because its high melt flow and moderate environmental stress-cracking resistance do not meet long-term pressure or stress-cracking demands. Those applications favor higher-molecular-weight HDPE grades with lower melt flow rates and documented ISO 9080 hydrostatic strength.
Shrinkage and Dimensional Stability Data for H6018 Are Conditional on Mold Temperature
As-molded shrinkage of H6018 is not a single value; it responds to cooling rate, part thickness, gate freeze-off, and tool temperature. In thin-wall packaging with wall sections below 1.5 mm, mold shrinkage in the flow direction is commonly around 1.5–2.0 %, while transverse shrinkage can be 0.5–1.0 % lower because of anisotropic orientation. These ranges are orientational, not producer guaranteed values; the current LyondellBasell data sheet should be consulted for the grade-specific measured range. Increasing mold temperature from 15 °C to 50 °C raises crystallinity and often reduces warpage after demolding, but it also increases post-mold shrinkage after 24 h. Processors measuring dimensional stability under ISO 294-4:2018 thermoplastic shrinkage methods should report mold temperature, holding pressure, and cavity design. Warpage in H6018 can arise when holding pressure is insufficient to compensate for volumetric shrinkage at the gate; maintaining gate-seal time at least 0.5 s beyond gate freeze-off and applying holding pressure of 40–60 MPa are typical starting points. Because H6018 is a highly crystalline polyethylene, post-mold aging at 23 °C can produce small additional shrinkage over 48 h; parts should be measured after this stabilization period if close tolerances are required. Dimensional changes in service above 60 °C can exceed these values due to thermal expansion, with a typical linear coefficient of thermal expansion for HDPE on the order of 1.0 × 10⁻⁴ K⁻¹ in isotropic moldings; anisotropic orientation raises the coefficient in the flow direction.
