Borealis HD22B-NNN is specified where extrusion blow moulding of rigid HDPE containers requires a combination of low melt index, high environmental stress-cracking resistance, and constrained parison sag. Grade selection is confirmed against melt flow behaviour measured to ISO 1133-1:2022 and density measured to ISO 1183-1:2019; the current Borealis technical datasheet remains the controlling source for property values, because the permissible regrind fraction and accumulator-head settings shift with batch melt viscosity. The scenarios below are limited to application categories in which medium- to high-molecular-weight HDPE of this type has documented industrial use: industrial chemical packagings, institutional cleaning and disinfection bottles, under-bonnet automotive reservoirs, agrochemical barrier containers, non-food recycled-content rigid packaging, and construction chemical packaging. Direct fuel contact, prolonged pharmaceutical solvent exposure, and food-contact uses are excluded where published data for HD22B-NNN is limited.

UN-Certified Jerrican Architecture for Oxidizer and Corrosive Service

Rigid transport packagings for sodium hypochlorite 12–15 wt%, phosphoric acid 75–85 wt%, and concentrated quaternary ammonium formulations use HD22B-NNN as the monolayer structural wall because the grade must sustain the ESCR and mechanical demands of UN certification. The package is certified as 3H1 or 3H2 under the United Nations recommendations; transport compliance is demonstrated under ADR/RID 6.1.5.3 drop, 6.1.5.4 leakproofness, 6.1.5.5 internal hydraulic pressure, and 6.1.5.6 stacking. The resin is processed at 100 wt% with 0.5–1.5 wt% chemical-resistant masterbatch; in-house regrind is limited to 20–30 wt% and is excluded for Packing Group I oxidizers unless each lot passes a repeat hydraulic pressure test at 250 kPa for 30 min.

Extrusion blow moulding of 20–30 L jerricans is performed on a single-screw grooved-feed extruder with L/D 24:1–30:1, barrier screw, and 1.2–2.0 mm die gap. Melt temperature is set between 190 °C and 210 °C; blow pressure is 0.7–0.9 MPa; mould cooling water is held at 8–15 °C. Parison programming is required to maintain wall thickness from 2.0 mm at the neck and bottom chime to 1.2 mm in the body, avoiding thin-out at the handle bridge. The critical defect is pinch-off weld porosity: reducing the die gap below 1.0 mm to lower shot weight reduces weld compression and creates paths for chemical ingress. Destructive inspection of weld flash at 20× magnification and leak testing after de-flashing are mandatory. Finished product types are 10 L, 20 L, 25 L, and 30 L jerricans and 60 L drums.

Monolayer bottles for institutional disinfection and cleaning products—sodium hypochlorite 5–10 wt%, hydrogen peroxide 3–8 wt%, and quaternary ammonium compounds—require a balance of stress-crack resistance at moulded-in chime notches and rapid filling-line dimensional stability. HD22B-NNN is blended with 1.5–2.0 wt% white PE masterbatch and 0.1–0.3 wt% antistatic concentrate; the virgin fraction is maintained at or above 80 wt%, with the balance as clean in-house regrind from deflashing. Compliance includes EU Detergent Regulation (EC) No 648/2004 for the filled product, Regulation (EC) No 1272/2008 CLP for hazard classification, and Directive 94/62/EC for packaging waste. Fillers specify ESCR testing per ASTM D1693-21 to avoid field cracking. Production uses a shuttle extrusion blow moulder with 60 mm screw, L/D 26:1, and six-station clamp. Melt temperature is held between 185 °C and 200 °C; mould temperature is 10–20 °C. Bottle weight is 42–55 g for 1 L formats, with wall thickness not less than 0.7 mm in the lower chime. Finished types include 750 mL, 1 L, and 5 L bottles with 28 mm and 38 mm neck finishes for trigger spray and closure systems.

What Changes When HD22B-NNN Is Deployed in Under-Bonnet Reservoir Blow Moulding?

Under-bonnet washer reservoirs and coolant overflow bottles convert from standard HDPE to HD22B-NNN when heat-aging requirements exceed 150 °C dry air for 500 h and when ESCR after immersion in 50 vol% ethylene glycol/water at 70 °C must remain above 100 h under ASTM D1693-21 condition B. Compliance is driven by ELV Directive 2000/53/EC heavy-metal annexes for lead, cadmium, mercury, and hexavalent chromium; REACH SVHC declarations; and OEM impact specifications aligned with ISO 179-1:2023. The formulation is 100 wt% HD22B-NNN with 0.3–0.8 wt% heat-stabilised black masterbatch; production regrind may be introduced up to 25 wt% after three heat-aging cycles confirm no loss in weld-line elongation.

Processing is performed on a single-station or dual-station accumulator-head EBM with 70–90 mm screw, L/D 25:1, and accumulator volume of 2–5 L. Die gap is 1.5–3.0 mm; melt temperature 195–215 °C; blow pressure 0.6–0.8 MPa; cooling water 10–15 °C. Finished reservoirs of 3 L, 4 L, and 5 L nominal volume must pass leak testing at 50 kPa internal air pressure and torque retention on heat-stake inserts. A boundary condition is premature mould opening: if the part surface temperature is above 65 °C, snap-fit bosses exhibit post-mould warpage after 24 h.

Agrochemical Barrier Bottle Layer Distribution and Solvent Resistance

Co-extrusion blow moulding of 1 L, 2.5 L, and 5 L crop-protection containers for xylene, cyclohexanone, and surfactant-containing formulations places HD22B-NNN as the structural HDPE layers in a three- to six-layer stack. The total HDPE fraction is 68–75 wt%, with 3–5 wt% maleic anhydride-grafted PE tie resin and 3–5 wt% EVOH barrier core; the balance is assigned to regrind layers only after permeation validation. Transport compliance is demonstrated under UN 3H1/Y certification and ADR 6.1.5.3 drop, 6.1.5.4 leakproofness, and 6.1.5.5 internal pressure tests. Crop-protection packaging also references Regulation (EU) No 547/2011 for label surface adhesion. Layer distribution is 25–30 wt% outer HDPE and 40–45 wt% inner HDPE; the inner skin is not replaced with post-consumer reclaim because solvent uptake can raise permeation above 0.5 g/(m²·day) when measured on 500 µm films according to ASTM F739-20 at 40 °C.

Processing is performed on a co-extrusion shuttle or wheel machine with 6–8 stations and individual layer screws. Melt temperatures are 195–210 °C for HD22B-NNN, 200–220 °C for EVOH, and 185–205 °C for tie resin through a multi-manifold die with 1.5–2.5 mm gap. The finished products include barrier bottles for emulsifiable concentrates, suspension concentrates, and aqueous solutions, typically with 38 mm and 45 mm neck finishes and induction-sealed closures. Published data for this specific configuration is limited when the solvent blend contains high fractions of methyl acetate or dimethylformamide; those formulations require separate permeation validation.

When post-consumer HDPE bales are converted into non-food rigid containers, blended formulations containing 70–85 wt% HD22B-NNN and 15–30 wt% washed PCR flake restore ESCR and parison hang strength that would otherwise be lost from recycled grades with fractional melt indices below 0.15 g/10 min. Compliance for the blend is assessed under REACH Article 33 for SVHC notification, REACH Annex XVII restrictions, and EU Directive 94/62/EC for heavy metals; where the finished container carries UN certification, each PCR batch must pass the same ADR 6.1.5.3 drop and 6.1.5.5 internal pressure tests as virgin material, and marker substances in the PCR must not exceed 100 ppm total bromine and chlorine. Compounding uses a 40:1 L/D co-rotating twin-screw extruder with vacuum degassing at -0.06 MPa and screen filtration 125–250 µm; the pelletised output is then extrusion blow moulded at 190–215 °C, with die gap adjusted 10–15% wider than virgin HD22B-NNN to compensate for higher melt viscosity. Finished product types are 5 L and 10 L non-food utility containers, waste-oil collection jugs, and internal plant storage pails; these are not intended for food-contact or aggressive oxidizer service.

When Construction Chemical Containers Require Stiffness Above Standard HDPE Pails

Liquid admixture and waterproofing-compound containers for polycarboxylate ether superplasticizers, sodium silicate hardeners, and epoxy curing agents are specified when the filled mass exceeds 20 kg and the stacked pallet load applies sustained compression at 40 °C. In this configuration, HD22B-NNN is used at 90–95 wt% with 5–10 wt% calcium carbonate masterbatch to raise top-load rigidity while retaining pinch-off weld integrity; the masterbatch addition must be limited to this range because higher loadings reduce Izod impact below the threshold of 4 kJ/m² measured by ISO 180:2023. Compliance for the package is under CLP 1272/2008 and Directive 94/62/EC, with UN certification required only where the filled liquid is classified as corrosive or environmentally hazardous.

Production uses a continuous shuttle EBM with 80 mm screw and L/D 28:1, melt temperature 190–210 °C, die gap 2.0–3.5 mm, and mould cooling at 8–12 °C. Weld-flash removal must be completed before the pail wall cools below 50 °C to avoid notch formation at the handle slots. Finished products are 15 L and 20 L pails with handle slots and tamper-evident lid seats.