Sinochem Quanzhou HDPE HHM5502BN is a hexene-copolymer blow-molding high-density polyethylene with a nominal melt flow rate of 0.35 g/10 min at 190 °C/2.16 kg under ASTM D1238 and a density of 0.955 g/cm³ under ISO 1183-1. United Nations certified monolayer jerrycans and tight-head drums produced from this grade are specified for aggressive liquid chemicals, aqueous agrochemical intermediates, cleaning agents, and oil additives. Packaging intended for dangerous goods transport is qualified under ADR/RID, IMDG Code, and DOT 49 CFR Part 178, with compatibility guidance under ISO 16101; hydrocarbon-based substances require evidence of environmental stress crack resistance under ASTM D1693 Condition B before the packaged goods are approved. In 5 L–30 L 3H1/Y jerrycan production, the charge typically runs 100 wt% virgin HHM5502BN or 85 wt% virgin with 15 wt% in-house regrind recovered from flash and rejected preforms; carbon black masterbatch is metered at 1.0–2.0 wt%, processing aid at 0.2–0.5 wt%, and the regrind fraction is kept below 20 wt% to limit lot-to-lot ESCR variation. The extrusion blow molding line uses a grooved-barrel extruder with 55–75 mm screw diameter and L/D 24:1–30:1, an accumulator head with servo-operated parison programming, melt temperature 180–210 °C, mold circuit temperature 12–18 °C, and blow pressure 0.6–0.8 MPa; wall profiling is biased toward the lift-handle bridge and bottom pinch-off to pass UN stacking and drop tests. Terminal products include 5 L, 10 L, 20 L, 25 L, and 30 L jerrycans, 60 L tight-head drums, and twin-neck liquid fertilizer containers.

Why does HHM5502BN maintain ESCR in agricultural chemical packaging at high regrind loads?

For agricultural chemical packaging, the capacity to process uncontaminated plant scrap at up to 20 wt% without destroying notched-tensile environmental stress crack resistance is the main qualification criterion. Agrochemical bottles and jerrycans are qualified as UN 3H1/Y packages and are placed on the EU market under Regulation (EC) No 1272/2008 classification and labelling obligations; the decisive polymer test methods are ASTM D1693 for ESCR and ISO 16770 for full-notch creep. In a monolayer 1 L–20 L bottle formulation, HHM5502BN represents 75–90 wt%, in-house regrind 10–20 wt%, carbon black/UV masterbatch 1.5–2.5 wt%, and antistatic masterbatch 0.1–0.3 wt% where filling lines require surface resistivity control. The blow molding process runs on single-station shuttle machines with 40–60 mm grooved-barrel extruders, L/D 24:1–28:1, melt temperature 190–210 °C, mold temperature 10–15 °C, and parison profiling that increases the pinch-off region wall thickness to 3.0–4.5 mm to resist cracking along the parting line. Terminal products include 1 L, 5 L, 10 L, and 20 L bottles for emulsifiable concentrates, suspension concentrates, and soluble powders. Regrind levels above 20 wt% are not recommended because ESCR retention may become batch-dependent, and lot-specific testing under ISO 16770 is then required.

Fuel tanks, diesel exhaust fluid reservoirs, and hydraulic oil tanks blow-molded from HHM5502BN exploit the resin’s high melt strength to minimize parison sag and the high molecular weight to resist stress cracking from fuel constituents. Regulatory compliance for automotive fuel tanks is governed by ECE R34 for approval of fuel tanks in vehicles, FMVSS 301 for fuel system integrity in the United States, and SAE J2665 for permeation measurement; emission limits are aligned with EPA and Euro evaporative requirements. In monolayer fluorinated tank production, HHM5502BN is used at 100 wt% by mass, carbon black concentrate at 1.5–2.5 wt%, antioxidant masterbatch at 0.2–0.5 wt%, and the interior surface is post-fluorinated with a fluorine-nitrogen mixture containing 0.5–2.0 vol% fluorine at 25–60 °C to reduce hydrocarbon permeation; for coextruded six-layer tanks, HHM5502BN forms the outer and inner structural layers at 70–85 wt% of the total wall, EVOH barrier at 1.5–2.5 wt%, and maleic anhydride-grafted polyethylene tie resin at 3–7 wt%. Production requires a 3D blow molding machine with servo-controlled die gap, mold temperature 40–70 °C, post-molding cooling fixtures, and fuel sender boss dimensional verification; extrusion melt temperature is kept at 190–215 °C to avoid thermal degradation of barrier layers. Terminal products include 40–90 L passenger car fuel tanks, 10–30 L construction machinery auxiliary tanks, and 10–50 L diesel exhaust fluid containers. Monolayer fluorinated tanks are limited to fuels with low aromatic content unless barrier performance is validated by the fuel supplier; EVOH coextruded structures are required for aggressive oxygenated fuel blends.

IBC inner bottle manufacture with HHM5502BN demands controlled die swell.

When molding intermediate bulk container inner bottles, the converter uses HHM5502BN as the monolayer liner resin because the grade provides the required side-wall stiffness, stress-crack resistance, and weld-line integrity under hydrostatic pressure. The IBC inner bottle is qualified under UN 31HA1/Y for liquid dangerous goods and, where the liner is used for non-hazardous foodstuffs, EU 10/2011 and FDA 21 CFR 177.1520 must be verified for the specific grade and conversion plant. Formulation for a 1,000 L or 1,250 L liner typically consists of 80–100 wt% virgin HHM5502BN, 0–20 wt% uncontaminated regrind, UV masterbatch at 0.5–1.5 wt% for outdoor storage, and antistatic masterbatch at 0.1–0.5 wt% when solvent-based products are filled. Production uses a large accumulator-extrusion blow molding machine with die diameter 200–350 mm, shot weight capacity 15–25 kg, platen width above 2,000 mm, mold cooling water inlet 8–12 °C, and parison profiling that compensates for measured die swell and parison sag over the 2–4 m drop length; wall thickness is mapped to maintain 2.0–3.5 mm in the lower sidewall and 4.0–6.0 mm around the top fill neck and discharge valve boss. Terminal products include 1,000 L and 1,250 L IBC inner bottles with top fill neck diameters of 150–225 mm, integrated discharge valve sockets, and calibrated sight lines for fill level control.

When coextruded with EVOH or PA barrier layers, HHM5502BN shifts from monolayer packaging to food-contact barrier bottles

For barrier bottle structures intended for edible oil, soy sauce, vinegar, mayonnaise, and shelf-stable concentrates, HHM5502BN functions as the load-bearing polyolefin layer. The compliance framework includes EU 10/2011 with Annex II specific migration limits for plastic food-contact materials, FDA 21 CFR 177.1520 for olefin polymers, and GB 9685-2016 for food-contact additives used in the Chinese market; converters must validate organoleptic neutrality and overall migration on the finished bottle, because additive masterbatch composition and regrind quality can shift migration resistance. In a four-layer coextrusion blow molding formulation, HHM5502BN structural layers account for 60–85 wt% of the wall, regrind layer 10–25 wt%, EVOH or PA barrier 1–3 wt%, and tie resin 1–3 wt%; the barrier layer is kept separate from the regrind layer to prevent interfacial contamination. Extrusion blow molding is run with a multilayer die head at 190–210 °C for the HDPE streams, 200–220 °C for the EVOH stream, and 10–15 °C for the mold circuit; the parison program is adjusted to maintain barrier layer continuity in the pinch-off zone and around the neck finish. Terminal products include 0.5 L–5 L bottles for edible oil, soy sauce, vinegar, and shelf-stable sauces, as well as 3 L–10 L barrier bottles for liquid food concentrates. Regrind levels above 25 wt% or non-food-contact scrap are not admissible in the outer food-contact layers unless migration testing demonstrates compliance.

Large-volume industrial water storage tanks, dosing vessels for water treatment chemicals, and chemical neutralization sumps are blow-molded from HHM5502BN when stiff side walls and corrosion resistance are required without the weight of steel. For potable-water contact applications, certification under NSF/ANSI/CAN 61 and relevant EU 10/2011 or national approvals is required; for industrial service, mechanical design is verified under DVS 2205 for thermoplastic tanks or the purchaser’s pressure and thermal load specification. Formulation ratios for outdoor UV-stable service are HHM5502BN 100 wt% virgin, carbon black masterbatch 2.0–3.0 wt%, regrind up to 15 wt%, and antioxidant masterbatch 0.2–0.4 wt%; calcium carbonate filler is kept below 5 wt% to limit low-temperature impact loss. Production is carried out on single-station or rotary blow molding equipment with melt temperature 180–205 °C, mold temperature 8–15 °C, and blow pressure 0.8–1.0 MPa; for tanks above 500 L, cooling time is the main cycle driver and is set to maintain 3–8 °C mold exit surface temperature before demolding. Terminal products include 200 L, 500 L, and 1,000 L closed-top storage tanks, 300 L conical dosing tanks, chemical filter housings, and float balls for level control in water and wastewater systems. For potable-water service, the converter must confirm that the specific HHM5502BN lot, pigment package, and processing conditions do not introduce substances exceeding the applicable migration limits.