Monolayer extrusion blow molding of household chemical containers from Braskem HDPE AC59 is executed on continuous shuttle or reciprocating screw machines with 60–80 mm grooved-feed extruders at L/D ratios between 24:1 and 30:1. Melt temperature at the die head is maintained at 190–210 °C; barrel zones are set with a flat-to-reverse profile from 180 °C in the feed zone to 195–205 °C in the metering section so that excessive shear heating does not lower melt strength before parison exit. Die gap is adjusted from 1.2 mm to 1.8 mm depending on bottle capacity, and the parison programmer is configured to increase wall thickness at the bottom pinch-off and handle attachment zones by 15–30% over the nominal wall. Mold temperature is held at 10–25 °C with turbulent-flow chilled water at 8–12 °C; rapid quenching raises the amorphous fraction at the surface but introduces frozen-in stress, so a minimum mold temperature of 12 °C is imposed for hypochlorite bleach and alkaline cleaner containers. The formulation for general laundry detergent and fabric softener bottles consists of 97–98 wt% AC59, 2–3 wt% polyethylene-carrier color masterbatch, and 0–0.2 wt% processing aid where melt fracture is observed. Clean, dry internal regrind from the same product line is added up to 20 wt% for non-oxidizing formulations; bottles filled with sodium hypochlorite, hydrogen peroxide, or high-pH degreasers are typically run 100% virgin because regrind heat history increases the free radical population that accelerates oxidative chain scission. Release testing anchors on ASTM D1693-15 ESCR in 10% Igepal CO-630 at 50 °C, ASTM D1505 density, and ASTM D1238 melt flow rate at 190 °C/2.16 kg. Typical AC59 lot values reported on certificates of analysis are 0.30 g/10 min melt flow rate and 0.954–0.956 g/cm³ density. Terminal products are 500 mL, 1 L, and 5 L bottles for liquid detergents, fabric softeners, multi-surface cleaners, and disinfectant formulations packaged under CLP-compliant labeling.

What Limits Regrind Levels in Food-Contact HDPE Bottles?

In food-contact blow molding, the regrind ceiling is set by migration compliance rather than by viscosity loss. Braskem HDPE AC59 is processed as monolayer food packaging only when the supplied lot is covered by a food-contact statement under FDA 21 CFR 177.1520 for olefin polymers and the relevant EU Regulation (EU) No 10/2011 migration limits. Overall migration into fatty food simulant D2 must remain below 10 mg/dm², and processors quarantine regrind by production campaign. Closed-loop, uncrosslinked scrap from the same food-grade lot is re-fed at 10–30 wt% for dry goods such as sugar, salt, and powdered beverage mixes; for fatty liquids such as edible oil, and for acidic liquids such as vinegar, the regrind fraction is reduced to 0–15 wt% or eliminated because polar migrants and oxidized species concentrate in the recycled melt stream. Extrusion conditions use a 60 mm barrier screw with temperature settings from 180 °C in the feed to 200–210 °C at the die head, screw speed between 40 rpm and 70 rpm, and a blow-up ratio of 2.0:1 to 2.8:1. The die head is purged after color changes to avoid gel streaks, and the melt is filtered through a 40/60 mesh screen pack where visible contamination is detected. Terminal products include 500 mL edible oil bottles, 750 mL vinegar bottles, 1 L soy sauce containers, and 2 L syrup bottles. Release testing for food-contact packaging is governed by EN 1186 overall migration, EN 1622 sensory evaluation for odor and taint, and ASTM D2463-15 drop impact after 24 h conditioning at 23 °C.

Pharmaceutical and Personal Care Bottles: Dimensional Stability and Torque Retention

Pharmaceutical and personal care containers made from Braskem HDPE AC59 are converted on extrusion blow molders with closed-loop parison weight control because neck finish roundness and wall distribution govern downstream capping torque. A 28 mm tamper-evident neck must hold roundness within 0.15 mm after cooling, otherwise removal torque decays below the closure supplier specification. Melt temperature is held at 190–205 °C, mold temperature at 15–25 °C, and blow pin coolant at 7–10 °C. The screw has a low-shear mixing section to disperse color without generating excessively high melt temperature on a grade with nominal 0.30 g/10 min MFR. Formulation is 100% virgin resin with 1–2 wt% pharmaceutical-grade masterbatch; antistatic additive is used at 0.1–0.3 wt% only when static charge interferes with filling lines. Compliance is evaluated against USP <661.1> for plastic packaging systems and Ph. Eur. 3.1.3 for polyolefins, with extractable and heavy-metal limits per the purchaser’s quality agreement. Terminal products are 100–500 mL shampoo bottles, 200–400 mL body wash bottles, 60–250 mL solid-dose packer bottles, and 100 mL syrup bottles. Bottle release tests include top load per ASTM D2659-16 measured at 23 ± 2 °C after 48 h, drop impact per ASTM D2463-15 at -20 °C to simulate cold-chain distribution, and cap torque retention after 28 days at 40 °C. Torque decay in HDPE neck finishes is governed by stress relaxation of the semi-crystalline structure and creep of the closure liner; initial removal torque is usually set at 0.5–1.0 N·m, but published data for AC59 under accelerated aging beyond 40 °C is limited.

When Jerrican Wall Thickness Drops Below 1.4 mm

Industrial jerrycan production from Braskem HDPE AC59 is driven by UN transport packaging performance rather than visual appearance. For Packing Group II liquids, a 5 L jerrycan is drop tested at 1.2 m at -18 °C and hydrostatically tested at 100 kPa; the wall section adjacent to the bottom pinch-off, handle bridge, and side seams must not fall below 1.4 mm after blow-up. Processors use accumulator-head blow molders with parison programming profiles that deliberately thicken the parison by 20–35% at the bottom and handle regions. Melt temperature is controlled at 190–210 °C, die gap at 1.5–2.5 mm, and mold temperature at 10–20 °C. Regrind from the same UN-certified line is added at 10–25 wt%; higher regrind fractions reduce low-temperature drop survival and melt strength, increasing rejections at the pinch-off weld. Terminal products are 5 L and 10 L HDPE jerrycans for lubricants, hydraulic oils, solvent degreasers, and agrochemical formulations. Qualification is performed with ASTM D1693-15 ESCR using 100% Igepal CO-630 at 50 °C and ASTM D638-14 Type IV tensile after 30 days immersion in the intended filling liquid; compatibility with hydrocarbons and ester-based lubricants must be confirmed separately because swelling reduces yield stress in the pinch-off zone.

Blow-molded automotive fluid reservoirs and emission-reduction fluid containers from Braskem HDPE AC59 are produced on 3D suction blow molding machines when the geometry includes convoluted underfill channels or hidden attachment bosses. Extrusion uses a 65–90 mm barrier screw with melt temperature between 200 °C and 220 °C; the higher melt temperature compensates for the longer parison path in 3D molding and prevents premature freezing at the mold pinch line. Mold temperature is held at 12–22 °C with localized cooling inserts around thick bosses. Carbon black masterbatch is dosed at 2.0–2.5 wt% for UV resistance in underhood and exterior installations; clean internal regrind is added up to 15 wt%, provided the scrap is free of engine oil, grease, or windshield fluid residue. Terminal products include 2–6 L coolant recovery bottles, 4–8 L windshield washer reservoirs, and 10 L diesel exhaust fluid containers. The diesel exhaust fluid container is the most restrictive application because ISO 22241-3 limits impurities that poison selective catalytic reduction catalysts; converters therefore purge the extruder with virgin AC59 before the DEF campaign and avoid calcium stearate or amine-based additive packages. Dimensional verification uses wall-thickness scanning on a production-scale blow molder, and thermal cycling from -40 °C to 120 °C is performed on welded assemblies; published data for AC59 in this exact underhood configuration is limited.

Large-volume technical containers for water treatment polymers, pool-shock chemicals, and dairy sanitizers are blow molded from Braskem HDPE AC59 on accumulator-head machines with 80–120 mm grooved-feed extruders. The target parts are 10 L, 20 L, and 25 L carboys with integrally molded handles and UN 3H1 certification where required. Melt temperature is set at 200–215 °C; die gap is increased to 1.8–2.8 mm to maintain parison wall thickness across the long handle section. Mold temperature is kept at 10–20 °C. The formulation for industrial polymer or detergent carboys contains 0–20 wt% internal regrind; for pool-shock and calcium hypochlorite containers the regrind fraction is zero and the colorant is selected from oxidizer-stable inorganic pigments. The limiting degradation mode in pool-shock packaging is oxidative chain scission accelerated by metal ions and heat history, so the converter avoids iron-based pigments and copper-containing fittings. Terminal products are 10 L and 25 L carboys for polyaluminium chloride, sodium hypochlorite, peroxide-based sanitizers, and alkaline clean-in-place concentrates. Release criteria include ASTM D1693-15 ESCR with 10% Igepal CO-630 at 50 °C, ASTM D638-14 Type IV tensile after 30-day chemical immersion, and UN drop testing for the filled container at the applicable packing group.