| HS Code | 965866 |
As an accredited Braskem HDPE GM8250 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Braskem HDPE GM8250 is packaged in 25 kg polyethylene bags, typically 55 bags per pallet (1,375 kg total). |
| Container Loading (20′ FCL) | Braskem HDPE GM8250 high-density polyethylene, palletized in 25 kg bags, loaded into a 20-foot FCL for secure ocean transport. |
| Shipping | Shipping description: Braskem HDPE GM8250 is a non-hazardous polyethylene resin in pellet form. It is typically shipped in 25 kg polyethylene bags, octabins, or bulk containers. Not DOT/IMDG/IATA regulated. Store in a dry, clean area, away from heat and direct sunlight. Handle with standard industrial care. |
| Storage | Store Braskem HDPE GM8250 in a cool, dry, well-ventilated area away from direct sunlight, heat, sparks, and open flames. Keep containers or bags sealed to prevent moisture, dust, and contamination. Use clean, dry pallets, avoid excessive stacking, and rotate stock. Maintain good housekeeping; protect pellets from UV exposure and incompatible oxidizers. Keep away from strong acids, bases, and other incompatible materials. |
| Shelf Life | Braskem HDPE GM8250 has an indefinite shelf life if kept sealed, cool, dry, and away from direct sunlight and heat. |
On shuttle blow molders running 1 L sodium hypochlorite and quaternary ammonium disinfectant bottles, HDPE GM8250 is processed with a 65 mm grooved-feed extruder at L/D 25:1, barrel zones set from 170°C to 210°C, and a converging die head maintained at 195–215°C. The grade’s melt flow rate under ASTM D1238-20 at 190°C/2.16 kg is 0.25 g/10 min, and the density under ASTM D1505-18 is 0.955 g/cm³, which places it in the high-molecular-weight blow-molding band needed to limit parison draw-down in dual-cavity tooling. Processors typically dose 2.5 wt% to 4.0 wt% titanium dioxide white masterbatch in an HDPE carrier with matched melt index, adding the masterbatch at the throat via gravimetric feeder; this loading prevents blush at the pinch-off weld and ensures sidewall opacity at 0.6–0.9 mm programmed wall thickness. The same 1 L bottle is usually produced with 20–30% edge-trim regrind generated from deflashing and leak-tested rejects, but plant records show that exceeding 35% regrind reduces environmental stress-cracking resistance measured according to ASTM D1693-15, Condition B, 10% Igepal CO-630, because oxidised trim concentrates at the parison inner layer. Mold temperature is controlled to 10–20°C and blow air pressure is 0.6–0.8 MPa to maintain a blow-up ratio of 2.0:1 to 2.6:1 without introducing haze. The finished monolayer bottle is leak-tested at 20 kPa internal pressure and top-load tested to ASTM D2659-16 for capping torque resistance.
Because high-gloss cosmetic containers require low die-swell variation and controlled surface replication, 200 mL–500 mL shampoo, conditioner, and liquid-soap bottles are run on continuous-wheel or shuttle machines using HDPE GM8250 at melt temperatures of 185–205°C, with a die gap of 1.2–1.6 mm and a parison blow-up ratio of 2.2:1 to 2.7:1; tighter die gaps produce excessive shear heat and gloss loss at the mandrel entry. Surface appearance is measured on production samples by ASTM D523-14 at 20° geometry, with 60° gloss values typically above 85 GU on the mould-cavity side when tooling is polished to SPI A-2 finish and mold temperature is held at 15–25°C. Fragrance and surfactant stresses require environmental stress-cracking resistance; incoming resin is qualified by ASTM D1693-15, Condition A, 100% Igepal CO-630 at 50°C, and the plant-level control is typically an F50 above 24 h at 100% concentration. To prevent sink marks at the neck finish, the preform is programmed with 15–30 point parison programming, reserving 0.9–1.3 mm wall in the shoulder, and the neck zone is cooled to 8–12°C using internal pin cooling. Additive loading for pearlescent or pastel shades is maintained at 0.5–1.5 wt% liquid colour concentrate or 1.0–2.0 wt% dry blend masterbatch, because higher pigment addition raises the compound melt viscosity and lowers die swell stability. Terminal bottles are dimensionally checked by ASTM D2911-16 for height and diameter, and capping torque is controlled at 1.8–2.3 N·m to avoid closure back-off without cracking the finish.
In dairy and edible oil packaging, extrusion blow-moulded HDPE GM8250 containers for pasteurised milk, edible oil, and water in the 250 mL–2 L segment are tested against EU Regulation No 10/2011 as amended, with overall migration limits of 10 mg/dm² for food-contact surfaces and specific migration limits applied to chromium, primary aromatic amines, and metal deactivators in the final article. Under FDA 21 CFR 177.1520, the olefin polymer is recognised for food contact; the finished monolayer is also evaluated under ANVISA Resolution No 105/1999 in Brazil when exported to Mercosur markets. Processing for dairy and oil bottles uses a 55–75 mm extruder with a barrier screw at L/D 24:1–28:1, barrel temperatures 180–210°C, and a die head at 195–215°C; degassing is not normally required if hopper air is conditioned below 50% RH, but humid ambient air above 70% RH can generate splay and requires either hopper drying at 70–80°C for 2–3 h or a vented extruder. Titanium dioxide and calcium carbonate direct food-contact masterbatches are limited to 2.0–4.0 wt% and 0.5–1.0 wt% respectively in this application, because higher CaCO₃ loadings reduce melt extensibility and make migration testing more sensitive to filler dispersion. Bottle sidewall thickness is programmed between 0.55 mm and 0.85 mm, with a concave bottom and flash trim to satisfy drop-impact resistance under ASTM D2463-15 at 1.2 m on filled containers at 23°C. The finished dairy bottle is rinsed and UV-sterilised; fat-containing simulants such as 95% ethanol or olive oil under EU Regulation No 10/2011 test conditions are used for compliance because edible oil and milk fat mobilise low-molecular-weight fractions more severely than aqueous simulants. Post-process crystallinity of the blow-moulded wall, measured by differential scanning calorimetry at 10°C/min under ISO 11357-3:2018, is typically 60–70%, which controls oxygen and water-vapour transmission through the monolayer structure. The final package is not intended for hot-fill above 70°C without pillow-mould water cooling; prolonged wall contact with hot oil above that temperature will lead to creep and should be avoided.
Where 20 L jerrican programmes require UN certification, large free-standing jerricans and stackable containers from 10 L to 30 L for liquid fertilisers, lubricants, and agrochemical concentrates are produced from HDPE GM8250 on accumulator-head blow molders with 80 mm or 90 mm extruders, L/D 24:1, barrel temperature profile 175–205°C, and accumulator shot capacities of 1.5–3.0 kg. The grade’s 0.25 g/10 min melt flow rate reduces parison sag compared with lower-viscosity blow-molding resins, but processors still compensate through a 30–50 point parison programmer to maintain 1.8–2.5 mm top-wall and 4.0–5.5 mm corner-wall thickness in the pinch-off zone. UN certification for dangerous goods packaging requires the assembled container to pass leakproofness under 49 CFR 178.604, hydrostatic pressure for 30 min under 49 CFR 178.605 at the pressure specified for the packed liquid’s specific gravity and packing group, drop impact from 1.2 m at 18°C on the weakest orientation under 49 CFR 178.603, and stack compression for 28 days at 40°C according to 49 CFR 178.606. HDPE GM8250 is typically compounded with 0.15–0.30 wt% hindered-amine light stabiliser, 0.05–0.10 wt% antioxidant, and 2.0–3.0 wt% medium-particle carbon black masterbatch for UV resistance in outdoor storage, while colouring to UN-approved pigmentation must not shift density outside the certified range. Drop-test failures trace to frozen-in stress at the flash line and to excessive regrind above 20%, because the recycled fraction incorporates degraded antioxidant and lower molecular weight tails; best practice is to feed 15–20% regrind with 80–85% virgin material and to set parison extrusion temperature at the upper band of 200–210°C to anneal the weld. Wall thickness distribution is verified by ultrasonic thickness gauging at a grid of 30–50 points per sidewall, and closure boss dimensions are held to BSP 2-in or Mauser 60-mm thread specifications depending on market. The empty container is leak-tested on a pressure-decay unit at 30–50 kPa, with pressure loss not exceeding 50 Pa over 30 s as a plant-level SPC limit.
Automotive windshield washer reservoirs and coolant overflow bottles blow-moulded from HDPE GM8250 are manufactured on single-station or double-station accumulator machines with clamp forces of 400–800 kN and extruder sizes from 70 mm to 90 mm; the resin is processed at 185–210°C melt temperature and the mold is held at 12–20°C to control post-mould shrinkage to 1.5–2.0% after 24 h. Automotive validation requires short-term heat ageing at 80–90°C for 500 h under ISO 188:2023 with tensile retention above 80% of the original yield stress, and impact resistance after ageing is verified by ISO 179-1:2023 Charpy notched specimens at -20°C, where the material must retain at least 6 kJ/m² to avoid brittle failure in cold-start conditions. In washer-fluid service, the bottle contains water-methanol or water-ethanol mixtures and non-ionic surfactants; chemical resistance is assessed by immersion in a 50/50 vol/vol methanol-water solution at 60°C for 7 days with mass uptake below 1.0%. Additive loadings for under-hood UV exposure are 2.0–2.5 wt% carbon black masterbatch or 0.3–0.5 wt% UV stabiliser plus 0.1–0.2 wt% antioxidant, because radiator grill openings transmit ultraviolet light and heat. A clear operational boundary is that unmodified HDPE GM8250 is not recommended for continuous immersion in pressurised engine coolant above 95°C or for continuous exposure to brake fluid, which migrates into the ethylene matrix and softens the pinch-off weld; in those positions a polyamide or a fluorination-treated HDPE liner is required. The reservoir is leak-tested at 15–25 kPa pressure and subjected to burst testing above 150 kPa to verify weld integrity; wall thickness at the mounting bosses is reinforced to 3.0–4.5 mm through parison programming to prevent cracking from insert torque of 6–10 N·m.
Across diagnostic reagent and nutraceutical tottle lines, monolayer tottles and dropper bottles from 100 mL to 1 L used for diagnostic wash buffers, lyophilised bead storage, and powdered nutraceuticals are blow-moulded from HDPE GM8250 on shuttle machines with 50–60 mm extruders and L/D 24:1, running barrel temperatures of 180–210°C and die gaps of 1.0–1.5 mm. Tight neck geometries are held by closed-loop parison programming with 15–25 point radial distribution, and neck inner diameter is controlled to ±0.3 mm to ensure dropper or plug-cap insertion torque of 1.5–2.5 N·m without stress whitening. The resin and finished containers are qualified under FDA 21 CFR 177.1520 and USP <661.1> for physicochemical testing, with additional bacterial endotoxin testing per USP <85> when the bottle is used for sterile diagnostic kit components. Water-vapour transmission through a 0.8 mm wall is controlled by process-induced crystallinity and is verified on 1 mm plaques by ASTM F1249-20 at 38°C, 90% RH, with typical values around 0.3–0.6 g/m²·day; this permits desiccant fill weights of 1–2 g for powder stability. Additive formulations are restricted to 0.5–1.0 wt% white masterbatch and 0.05–0.10 wt% acid neutraliser, because leachables from phenolic or amine-based antioxidants can interfere with enzyme-based diagnostic reactions; lubricant loadings are kept below 0.10 wt% to avoid haze. The terminal container is leak-tested by vacuum decay at -10 kPa and drop-tested empty at 1.2 m according to ASTM D5276-19; burst strength is typically above 250 kPa for a 500 mL round tottle.
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Braskem HDPE GM8250 is a high-molecular-weight high-density polyethylene resin supplied as pelletised feedstock for continuous extrusion blow molding of rigid containers, large-volume industrial packaging, and automotive fluid reservoirs. The grade is defined by a melt flow rate of 0.25 g/10 min at 190 °C/2.16 kg and a density of 0.955 g/cm³, measured according to ISO 1133-1:2022 and ISO 1183-1:2019. The low melt flow rate, relative to injection-molding HDPE, indicates high melt viscosity and high molecular weight, both of which contribute to parison integrity in large-part blow molding.
Typical end-use sectors include rigid packaging for agrochemicals, industrial cleaning fluids, and technical parts that require environmental stress crack resistance determined by ASTM D1693-21. The material is not normally selected for film blowing at narrow die gaps or for high-flow injection molding; the melt does not respond well to high-shear processing typical of those operations. Representative property values from the Braskem technical datasheet are shown in Table 1. These are typical values, not specification limits, and must be verified against the certificate of analysis for the production lot.
| Property | Test method | Representative value |
|---|---|---|
| Melt flow rate at 190 °C/2.16 kg | ISO 1133-1:2022 / ASTM D1238-20 | 0.25 g/10 min |
| Density at 23 °C | ISO 1183-1:2019 / ASTM D1505-18 | 0.955 g/cm³ |
| Tensile strength at yield, 50 mm/min | ISO 527-2:2012 / ASTM D638-14 | 28 MPa |
| Elongation at break | ASTM D638-14 | >600 % |
| Flexural modulus, 1 % secant | ASTM D790-17 | 1,250 MPa |
| Environmental stress crack resistance, F50, Igepal CO-630 Condition B | ASTM D1693-21 | >600 h |
| Vicat softening temperature, A50 | ASTM D1525-17e1 | 128 °C |
| Hardness, Shore D | ASTM D2240-21 | 64 |
The grade should not be processed at melt temperatures above 220 °C for extended hold-up times. Above this threshold, thermo-oxidative chain scission reduces the high-molecular-weight fraction and compromises environmental stress crack resistance in the molded article.
The differentiation is not limited to the melt flow index. GM8250 is characterised by a broad molecular weight distribution that increases the elastic component of the melt response. Under shear flow at 190 °C, the pressure drop through a 1.5 mm die is higher than that of a blow-molding HDPE with a melt flow rate of 0.8 g/10 min; the exact capillary rheometry figures are specific to the production configuration and should be measured on the installed die head. In industrial trials on 24:1 to 30:1 L/D single-screw extruders, the grade consistently requires a lower screw speed to maintain head pressure below 400 bar.
The higher elastic melt response also raises die swell. On a 1.5 mm die gap, the parison wall thickness after swell is typically 55–75 % greater than the die gap before closure. This characteristic must be accounted for when switching from a lower-molecular-weight blow-molding grade; tooling designed for a 0.8 g/10 min melt flow rate will produce non-uniform wall thickness if the blow-up ratio and preblow timing are not adjusted.
| Parameter | HMW-HDPE GM8250 class | Conventional unimodal blow-molding HDPE | High-flow injection-molding HDPE |
|---|---|---|---|
| Melt flow rate at 190 °C/2.16 kg | 0.2–0.3 g/10 min | 0.6–1.0 g/10 min | >10 g/10 min |
| Density | 0.954–0.957 g/cm³ | 0.954–0.958 g/cm³ | 0.955–0.960 g/cm³ |
| ESCR F50, Condition B | >600 h | 100–400 h | <30 h |
| Relative die swell through a 1.5 mm die | 55–75 % | 30–50 % | 10–25 % |
| Melt strength / parison sag resistance | High | Medium | Low |
| Processing head pressure at equal screw speed | High | Medium | Low |
The comparative data in Table 2 refer to resin classes rather than single production lots. For grade-to-grade substitution decisions, a full capillary rheometry sweep on the target die head is required because molecular architecture, not solely melt flow rate, controls die swell and melt strength.
When continuous extrusion blow molding is run on a 65 mm single-screw extruder with 25:1 L/D and a barrier screw, the following boundaries are observed. The melt temperature at the die exit should be held between 205 °C and 215 °C. Temperature variation greater than ±5 °C across the die circumference produces measurable differences in parison take-up length and sidewall thickness. Head pressure upstream of the screen changer should remain in the 250–350 bar range at normal output; an increase above 400 bar may indicate screen blockage, degraded melt homogeneity, or an excessively low die-head temperature. The die gap should be set between 0.8 mm and 1.8 mm depending on the target article mass, with a blow-up ratio of 2.0:1 to 3.0:1. Mold cooling water should be maintained at 10–20 °C; lower mold temperatures shorten cycle time but increase residual stress in the flash and pinch-off zones.Parison sag is the limiting defect in large containers. Because the grade retains a high-molecular-weight fraction, the parison length at mold closure can be maintained with a preblow timing window of approximately 0.5–1.0 s after parison extrusion begins. If preblow is delayed beyond this range, the parison thins at the upper shoulder and the finished part fails top-load testing according to ASTM D2659-16 or an equivalent compressive creep method. On high-output lines with shot times below 8 s, die-head controllers should use proportional-integral-derivative tuning with a reset time no longer than 60 s; slower reset times allow the thermal excursion to persist through several cycles.
The grade is not hygroscopic in the same manner as polyamide or polycarbonate, but surface condensation on cold pellets stored under relative humidity above 60 % may produce pinholes and splay on the parison surface. If pellet surface moisture is visible, a hopper dryer set at 70–80 °C for 1 h is sufficient to remove condensation without disturbing the stabiliser package.
Thermal degradation in high-molecular-weight HDPE is initiated by thermo-oxidative chain scission at elevated melt temperatures. The stabiliser package in GM8250 is designed for repeated heating and short-term hold-up, not for residence times above 20 min at 210 °C. In accumulator-head machines, the melt can stagnate in the corners of the die head; periodic purging with a HDPE having a melt flow rate greater than 1 g/10 min is required to evacuate degraded resin. Gel particles visible as hard specks in the parison wall generally indicate localised dead zones, not failure of the feed pellet quality.
Dynamic oscillatory shear at 190 °C shows a higher storage modulus relative to loss modulus at low angular frequencies. This elastic character is the source of parison stability, but it also reduces the upper shear-rate limit before sharkskin melt fracture. Capillary rheometry on similar HMW-HDPE resins indicates a critical shear rate for sharkskin in the order of 100–200 s⁻¹ at 210 °C; when sharkskin appears on the parison, linear output should be reduced or the die-head temperature raised to 210–215 °C, without exceeding 220 °C.
Barrier screws with a compression ratio of 2.5:1 to 3.2:1 and a Maddock mixing tip are preferred. Open-channel screws with low compression may not generate enough dispersive mixing for the high-molecular-weight fraction, resulting in parabolic wall-thickness variation across the part. Production lots of GM8250 typically show melt flow rate variation of ±0.05 g/10 min and density variation of ±0.002 g/cm³; this is narrow enough to avoid frequent die gap changes, but preblow timing may still require adjustment at lot changes.
When post-consumer recyclate is introduced at the feed hopper at 10 wt%, the apparent melt flow rate may increase by 0.05–0.15 g/10 min depending on contamination level and prior thermal history, and environmental stress crack resistance can fall below 600 h if low-molecular-weight recycled HDPE or polypropylene is present above 3 wt%. This is a cliff-edge response, not a linear dilution curve. Extrusion blow molding trials on 60 mm grooved-feed extruders indicate that maintaining ESCR above 400 h requires a melt temperature below 210 °C, and often requires a linear low-density polyethylene modifier at 5–15 wt% to recover impact toughness. The addition of recyclate also narrows the effective die gap tolerance because the elastic memory of the blend is lower than that of virgin GM8250; operators should expect more parison sag and should reduce blow-up ratio to 2.0:1 for initial trials.
Chemical exposure boundaries for GM8250 are typical for high-density polyethylene. The grade resists dilute mineral acids, alkalis, and aqueous salt solutions at ambient temperature, but it is unsuitable for continuous contact with strong oxidising acids such as fuming nitric acid or 98 % sulfuric acid, and with halogenated solvents. Environmental stress cracking is accelerated by polyethylene glycol ether surfactants at concentrations above 0.1 vol% at 60 °C; tanks or closures exposed to such fluids require pre-validation by ASTM D1693-21 or ISO 22088-3:2008 on the finished article, not on compression-molded plaques alone.
Compliance statements for Braskem HDPE GM8250 must be segregated by use condition. The grade may be evaluated against FDA 21 CFR 177.1520(c)(3.2a) for food-contact applications, but final-article migration testing under EU Regulation 10/2011 or equivalent regional legislation is required before commercial use; the datasheet does not by itself constitute food-contact certification. For pipe or pressure applications, long-term hydrostatic strength must be established by ISO 9080:2022, and the grade shall not be used in natural gas distribution or potable-water pressure pipe unless the specific long-term strength curve is published by the producer and accepted by the certifying body. For automotive fluid reservoirs, the molded part must be validated under the relevant original equipment manufacturer specification for permeation, hot/cold cycling, and chemical resistance; published data for this specific configuration is limited and must be generated on production tooling.
