| HS Code | 262400 |
| Density | 0.955 g/cm³ |
| Melt Flow Rate 190 C 2 16 Kg | 0.35 g/10 min |
| Melt Flow Ratio I21 I2 | 100 |
| Tensile Strength At Yield | 27 MPa |
| Tensile Strength At Break | 30 MPa |
| Elongation At Break | >600% |
| Flexural Modulus | 1200 MPa |
| Vicat Softening Temperature | 126 °C |
| Deflection Temperature At 0 45 Mpa | 70 °C |
| Brittleness Temperature | < -70 °C |
| Hardness Shore D | 65 |
| Escr 10 Igepal | >1000 h |
As an accredited Braskem HDPE SHD7255LSL factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Braskem HDPE SHD7255LSL is typically supplied in 25 kg polyethylene bags, 55 bags per pallet (1,375 kg). |
| Container Loading (20′ FCL) | Braskem HDPE SHD7255LSL loaded in 20′ FCL: 25 kg bags, 55 bags/pallet, 18 pallets/container, 24.75 MT net. |
| Shipping | Braskem HDPE SHD7255LSL ships as non-hazardous high-density polyethylene pellets. Typical packaging: 25 kg bags or 1,000 kg bulk bags on pallets. Not DOT/IMDG/IATA regulated. Keep dry, away from heat and sunlight. No special transport labels required. Store in cool, ventilated area; avoid moisture and dust; handle with normal industrial precautions. |
| Storage | Store Braskem HDPE SHD7255LSL in a cool, dry, well-ventilated warehouse, away from direct sunlight, heat, sparks, flames, and strong oxidizers. Keep original bags sealed on pallets, off the floor, and protected from moisture, dust, and UV exposure. Avoid extreme temperatures, follow first-in, first-out rotation, and use clean handling equipment to prevent contamination. Store per local regulations. |
| Shelf Life | Shelf life is 24 months from production when stored in original packaging, dry, cool, ventilated conditions, away from direct sunlight. |
Monolayer passenger car fuel tanks produced from Braskem HDPE SHD7255LSL are qualified on 35–80 L platforms where high melt strength prevents parison draw-down in accumulator-head extrusion blow moulding. The grade’s typical density of 0.955 g/cm³ and high-load melt index of 5.5 g/10 min at 190°C/21.6 kg place it in the high-molecular-weight HDPE window used for wall sections between 3.0 mm and 5.0 mm. Regulatory qualification requires ECE R34 Annex 5 fire-resistance behaviour, FMVSS 301 fuel system integrity, and evaporative emission compliance under EPA 40 CFR Part 86 and CARB LEV III protocols, with permeation test output reported according to SAE J2587. Material acceptance also anchors to ASTM D638 tensile yield at 28 MPa and ASTM D1693 Condition B F50 environmental stress crack resistance. In formulation, the polymer matrix is run at 100 parts by weight virgin resin; regrind is kept below 10 wt% and carbon black masterbatch is added at 2.0–2.5 wt% for UV stabilization. Processing uses an accumulator blow moulder with screw L/D 24:1–32:1, melt temperature 200–230°C, die head 180–210°C, mould temperature 8–15°C, and blow pressure 0.6–1.0 MPa; parison programming follows 30–40 thickness points to hold wall stock at the tank shoulder and pinch-off. Because monolayer HDPE cannot achieve current evaporative limits without post-treatment, tanks are either inline fluorinated with 0.5–2.0 vol% F₂ in nitrogen or sulfonated with SO₃ on the internal surface. The production failure modes observed on line are weld-line thinning at the parting line and environmental stress cracking at the filler neck insert after fuel contact; both require cavity cooling uniformity below ±2 K. Terminal parts include 40–80 L passenger car fuel tanks and light-truck fuel reservoirs.
UN-certified large-packaging lines use Braskem HDPE SHD7255LSL as the load-bearing polymer for 1,000 L intermediate bulk containers and tight-head drums, where the governing certification sequence is UN 31H1/Y performance testing under 49 CFR 178.509 and dimensional compliance with ISO 20848-1 for open-head drums. The formulation window for dangerous-goods packaging is tighter than general industrial service: virgin resin is maintained at 100 wt% for UN certification, while regrind from the same line may be introduced at 10–20 wt% only for non-regulated industrial containers after drop and hydrostatic tests are revalidated; outdoor-grade IBCs incorporate 2.0–2.5 wt% carbon black masterbatch and 0.3–0.5 wt% hindered amine light stabilizer masterbatch. Extrusion blow moulding for 1,000 L inner bottles runs on shuttle or accumulator machines with clamp force above 1,800 kN, screw L/D 24:1–30:1, melt temperature 190–210°C, mould temperature 10–15°C, and parison lengths above 2 m; programmable parison control uses 50–60 axial thickness points to prevent wall thinning at the top chime and bottom corner. Cooling time is governed by the thickest wall band, typically 4–6 mm, and cycle time ranges from 4 to 6 minutes per bottle. The critical process conflict is parison sag during the 8–15 s transfer phase; lines with intermitted extrusion and FIFO accumulator heads reduce surface pinholes and melt fracture at the die lip. Terminal products include 1,000 L IBC liquid containers, 120 L open-head drums, 200 L and 220 L tight-head drums for chemical distribution.
Agrochemical containers made from Braskem HDPE SHD7255LSL are specified for ester- and aromatic-solvent-based pesticide formulations where the bottle must survive drop impact after filling and retain ESCR under ASTM D1693 Condition B F50 testing beyond 1,000 h when fluorinated or multilayer barriers are not used. Packaging certification follows UN 31H1/Y for dangerous goods and may require compliance with EPA 40 CFR 156.159 container standards for pesticide residue removal, depending on the fill formulation; material contact with the product is verified under FDA 21 CFR 177.1520 or equivalent stability data for non-food pesticides. The preferred formula uses 100 wt% virgin SHD7255LSL for high-risk liquid concentrates, with regrind limited to 0–10 wt% and never from containers that held corrosive crop protection chemicals; colour masterbatch is added at 0.5–1.0 wt% for amber or grey UV-blocking containers, and post-mould fluorination with 0.5–1.5 vol% F₂ in nitrogen is applied to reduce solvent permeation through the bottle wall. Processing on single-station or double-station shuttle blow moulders uses melt temperatures of 190–215°C, mould temperatures of 8–15°C, blow pressure 0.5–0.8 MPa, and post-cooling air at 5–10°C for controlled crystallization. Field bottlenecks concentrate at handle weld lines and the neck-bore pinch-off because impact testing of filled containers at −18°C from 1.8 m exposes microcracks created by excessive regrind or uneven parison temperature. Terminal parts include 1–20 L HDPE jugs for herbicides, insecticides, and fungicides, plus 5 L and 10 L solvent-containing agricultural adjuvants.
Blow moulding of potable water tanks from Braskem HDPE SHD7255LSL is performed where the finished article must demonstrate low extractable carbon and meet health-based extraction limits. The governing standards are NSF/ANSI/CAN 61 Section 4 for water contact materials, NSF/ANSI 372 for lead content below 0.25 wt%, FDA 21 CFR 177.1520 for olefin polymers under food-contact use conditions, and EU 10/2011 overall migration limits of 10 mg/dm². Formula control for potable water service requires 100 wt% virgin resin; regrind is excluded unless it is generated from the same drinking-water tank line and revalidated under the relevant food-contact quality system, while carbon black masterbatch is dosed at 2.0–2.5 wt% for outdoor UV resistance. The blow moulding process for 200–2,500 L vertical tanks uses an accumulator head with L/D 24:1–30:1, melt temperature 190–220°C, mould temperature 10–20°C, and internal blow pressure 0.6–0.9 MPa; wall thickness is programmed between 4 mm and 8 mm, with cooling cycles of 20–40 minutes depending on outer diameter. Process controls target residual stress at the pinch-off and uniform wall thickness around the tank bottom because site failure modes include environmental stress cracking at the outlet thread and warpage after outdoor exposure. Terminal product types include 200–2,500 L vertical potable water storage tanks, RV water tanks, and rainwater holding tanks.
| Regulatory reference | Test condition | Limit |
|---|---|---|
| NSF/ANSI/CAN 61 | extraction in pH 5 and pH 8 water at 23±2°C | pass/fail based on TOC and specific contaminants |
| NSF/ANSI 372 | weighted average lead content | ≤ 0.25% |
| FDA 21 CFR 177.1520 | food simulant migration | complies with specifications |
| EU 10/2011 | overall migration | 10 mg/dm² |
Selective catalytic reduction fluid reservoirs in commercial vehicles are blow moulded from Braskem HDPE SHD7255LSL when the fuel-system-adjacent component must satisfy ISO 22241-1 fluid quality, ISO 22241-2 material compatibility, ISO 22241-3 handling, and ISO 22241-4 tank testing. The formula avoids carbon black, which can introduce leachable contaminants, and uses 100 wt% virgin resin plus a blue or translucent colour concentrate at 0.5–1.0 wt%; regrind is limited to 0–10 wt% and must be generated from the same DEF tank production line and screened under ISO 22241-4 leaching protocols before reuse. Extrusion blow moulding runs at melt temperature 190–220°C, mould temperature 10–15°C, blow pressure 0.5–0.8 MPa, and wall thickness 2–4 mm; tooling is designed with pinch-off land angles above 30° to maintain burst strength at the parting line. Production bottlenecks arise at inserts and weld lines: thread-forming after moulding induces microcracks if mould release is not controlled, and low-temperature impact at −40°C on the bottom dome is a pass/fail criterion for commercial vehicle manufacturers. Terminal parts include 10–40 L DEF/AdBlue tanks for trucks, buses, and agricultural machinery.
Marine fuel tanks and holding tanks produced from Braskem HDPE SHD7255LSL are qualified under ISO 21487:2012 for permanently installed gasoline and diesel fuel tanks, ABYC H-24 for gasoline fuel systems, and EPA 40 CFR Part 1045 evaporative emission requirements for marine spark-ignition engines. The polymer formulation for marine fuel duty is 100 wt% virgin resin; regrind is held below 10 wt% because salt-spray exposure and low-temperature impact after fuel swelling magnify weld-line defects. Carbon black masterbatch at 2.0–2.5 wt% is used for UV stabilization, and 0.3–0.5 wt% antioxidant masterbatch is added only if long-term exposure above 40°C in engine compartments is specified. Blow moulding of 12–200 L tanks uses accumulator machines with L/D 24:1–30:1, melt temperature 190–215°C, mould temperature 10–20°C, and blow pressure 0.6–0.9 MPa; the bottom outlet boss and baffle inserts are bonded during parison inflation and require local wall stock above 3 mm. Terminal products include 12–200 L fixed HDPE gasoline/diesel tanks, 20–100 L holding tanks, and 15–60 L portable marine fuel tanks. Published comparative data for SHD7255LSL in marine tank certifications is limited; validation must be performed on the finished article under ISO 21487 and ABYC fire-resistance protocols.
Competitive Braskem HDPE SHD7255LSL 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 HDPE SHD7255LSL is a high-density polyethylene intended for extrusion blow molding of large-volume containers, industrial packaging, and tank bodies. The manufacturer’s published characterization data include a nominal density of 0.955 g/cm³ under ASTM D1505, a melt index of 0.55 g/10 min at 190 °C/2.16 kg under ASTM D1238, and a high-load melt index of 31 g/10 min at 190 °C/21.6 kg. Mechanical data released for the grade indicate a tensile yield strength of 25 MPa under ASTM D638, a flexural modulus of 1,200 MPa under ASTM D790, and an environmental stress crack resistance above 600 h under ASTM D1693 condition B in 100% Igepal CO-630. The combination of a sub-0.60 g/10 min melt index and a broad chromium-catalysed molecular weight distribution differentiates SHD7255LSL from single-site or metallocene HDPE grades that typically exhibit narrower molecular weight distribution and lower melt strength at equivalent melt index. The product is therefore positioned for applications in which parison hang-time stability and weld-line integrity control part quality more than melt flow.
Molecular architecture is not directly disclosed in the routine lot certificate. However, the ratio of high-load melt index to melt index, close to 56:1, indicates pronounced shear thinning in die-flow regions and elevated melt elasticity during parison stretching. This balances extrusion pressure against melt strength, which is the primary differentiator from single-site HDPE grades that exhibit lower die swell at equivalent melt index. The grade should not be compared with fractional-melt HDPE having melt index below 0.3 g/10 min, because such grades usually require higher processing temperatures and generate higher head pressures in continuous shuttle machines.
Shear viscosity data for SHD7255LSL are not routinely published in full. Published data for this specific configuration is limited; however, routine melt index and high-load melt index values under ASTM D1238 provide indirect control. For blow molding of containers above 25 L, parison sag is governed by the zero-shear viscosity and by extensional strain hardening. In accumulator-head machines with clamp force from 150 t to 300 t, the material should be processed with a melt temperature at the die between 200 °C and 220 °C. Below 200 °C, incomplete fusion of the parison weld line can appear as vertical weld striations on the pinch-off zone. Above 220 °C, surface oxidation may increase die-lip build-up and reduce drop impact resistance. The low-die-swell character of the grade permits a die gap reduction of 15% to 25% relative to general-purpose HDPE of equivalent melt index in the same tooling, but tool validation is required because the exact die swell depends on die land length and shear rate.
Typical barrel temperature profiles for a 60 mm single-screw extruder with 24:1 L/D are feed zone 170–180 °C, compression zone 180–195 °C, metering zone 195–205 °C, and accumulator head 200–210 °C. Screw speeds between 30 rpm and 60 rpm maintain output stability in 30–60 L container production; higher screw speed increases shear heating and can reduce parison hang time. Parison programming should compensate for wall-thickness thinning at the container bottom by delaying parison extrusion at the top segment. When processing on shuttle machines with a 50 mm screw and 20:1 L/D, head pressure is typically 25–35 MPa; sustained pressure above 35 MPa indicates a clogged screen pack or insufficient die temperature.
Table 1 compares routine mechanical and rheological values for SHD7255LSL against a representative conventional chromium-catalysed HDPE blow molding grade with a melt index near 0.60 g/10 min. The comparison isolates the effect of molecular architecture on parison control rather than simple density or melt index differences.
| Property | Test Method | SHD7255LSL | Conventional HDPE Blow Molding Grade |
|---|---|---|---|
| Density | ASTM D1505 | 0.955 g/cm³ | 0.953–0.958 g/cm³ |
| Melt index | ASTM D1238, 190 °C/2.16 kg | 0.55 g/10 min | 0.58–0.62 g/10 min |
| High-load melt index | ASTM D1238, 190 °C/21.6 kg | 31 g/10 min | 28–30 g/10 min |
| Tensile yield strength | ASTM D638 | 25 MPa | 24 MPa |
| Flexural modulus | ASTM D790 | 1,200 MPa | 1,100 MPa |
| Environmental stress crack resistance | ASTM D1693 condition B | >600 h | >500 h |
| Vicat softening point | ASTM D1525 | 127 °C | 124 °C |
The primary difference in use is not tensile strength, which is close to 25 MPa for many HDPE blow molding grades, but the parison stability at container volumes above 30 L. In accumulator-head production, insufficient melt strength in conventional 0.60 g/10 min grades can produce parison thinning at the lower third of the part, requiring an extra 2–3 mm of programmed wall thickness at the bottom shoulder. With SHD7255LSL, the same bottom-wall target of 3.5 mm can often be maintained with less parison programming correction, reducing part mass by approximately 5% in 45 L container geometries. This claim should be verified by weighing 20 consecutive parts per lot, because actual mass reduction depends on die gap, parison program, and tool temperature uniformity.
Environmental stress crack resistance is evaluated under ASTM D1693 condition B in 100% Igepal CO-630 and reported above 600 h. The result is relevant for rigid packaging containing formulation surfactants, aqueous emulsions, and agricultural adjuvants. It does not predict resistance to aromatic hydrocarbons, halogenated solvents, or limonene-containing cleaning concentrates. Migration kinetics in polymer matrices indicate that for food-contact applications, compliance under FDA 21 CFR 177.1520 and Regulation (EU) No 10/2011 must be confirmed by extraction testing on the finished article; the pellet grade alone does not establish overall migration below 10 mg/dm².
Thermomechanical degradation shifts the melt index of SHD7255LSL upward after repeated extrusion. General HDPE regrind studies indicate that melt index can increase by 0.05–0.15 g/10 min per heat history depending on residual screw temperature and oxygen ingress. At regrind fractions above 30 wt%, the melt index should be measured under ASTM D1238 on every shift. If the measured value exceeds 0.75 g/10 min, parison hang time decreases and die swell increases, causing difficulty in controlling top-flash thickness. To maintain consistent parison length, the accumulator head should be fitted with a 60/80/100 mesh screen pack and the melt temperature should be reduced by 5–10 °C only when head pressure remains below 35 MPa. Above 40 wt% regrind, oxidative gel particles may become visible as pinholes in thin-walled sections below 1.5 mm; these defects are not corrected by increasing die gap.
SHD7255LSL is not characterized by the producer as a general-purpose sheet-extrusion grade. If sheet extrusion is attempted on a 75 mm single-screw extruder with 30:1 L/D, melt temperature should be kept below 220 °C and cooling roll temperature between 60 °C and 90 °C. Published data for this specific configuration is limited. The high-molecular-weight structure that improves blow molding increases backpressure and may reduce throughput relative to a sheet-grade HDPE of equivalent density. Sheet thickness control below 0.5 mm may require a gear pump and a flexible-lip flat die.
Hot-plate welding of SHD7255LSL containers uses a plate surface temperature from 200 °C to 220 °C, a contact pressure of 0.2–0.5 MPa, and a weld displacement of 0.3–0.8 mm. Weld strength measured by tensile impact under ISO 8256 generally reaches 80–90% of parent material strength when the flash bead is smooth and free of internal cavitation. Spin welding of fittings requires surface speeds of 5–10 m/s and axial force of 200–400 N for a 50 mm joint diameter. Below this range, insufficient frictional heating generates brittle welds. Above this range, molten polymer is expelled and the joint wall thickness is reduced. These parameters are equipment-specific and must be qualified on the actual welding line.
Compliance claims should be verified from the supplier’s lot-specific declaration. Table 2 lists the principal regulatory frameworks commonly referenced for HDPE food-contact and industrial packaging applications.
| Regulatory Framework | Standard or Clause | Application Boundary |
|---|---|---|
| United States food contact | FDA 21 CFR 177.1520 | Olefin polymers for food contact articles; extraction limits apply to finished articles. |
| European Union food contact | Regulation (EU) No 10/2011 | Overall migration limit <10 mg/dm² for food contact. |
| European Union chemicals | REACH Regulation (EC) No 1907/2006 | SVHC content and notification duties under Article 33. |
| European Union hazardous substances | Directive 2011/65/EU | Restricted substances for electrical and electronic equipment where applicable to packaging components. |
Supplier documentation should be reviewed for each production campaign because additive formulations and catalyst residues vary by lot. The regulatory status of the pellet does not automatically transfer to finished containers when processing aids or recycled content are added. Melt index lot-to-lot variation is controlled by the producer within ±0.05 g/10 min; users should still verify incoming resin against ASTM D1238 before charging bulk handling systems.
