ALATHON M5372 from LyondellBasell is a narrow-molecular-weight-distribution high-density polyethylene injection molding grade with a nominal melt flow rate of 52 g/10 min under ASTM D1238 at 190°C/2.16 kg and a nominal density of 0.954 g/cm³ under ASTM D1505. The application-specific processing windows presented below are compiled for raw material qualification, tooling specification, and supplier evaluation. Published data for non-standard tooling configurations is limited.

On multi-cavity thin-wall dairy packaging lines, ALATHON M5372 is used when wall sections below 0.60 mm require a longer flow length at reduced injection pressure. Melt flow-rate measurement under ASTM D1238 at 190°C/2.16 kg yields 52 g/10 min, but runner balance and hot-runner tip geometry still control short shots in 32- to 64-cavity stack tools. Direct food-contact compliance rests on 21 CFR 177.1520(c) Items 3.1a and 3.2a, EU Regulation (EU) No 10/2011 with an overall migration limit of 10 mg/dm², and China GB 4806.7-2016 where national certification applies. At the compounding hopper, virgin resin is processed at 100 wt% or with a food-contact white masterbatch at 2.0 wt% ± 0.5 wt%; slip amide concentrate for lid denesting may be added at 0.1–0.3 wt% of the final compound. The injection molding process on 350–650 t hydraulic or hybrid presses with general-purpose screws of 22:1–25:1 L/D and compression ratio 2.5:1–3.0:1 operates with barrel zones from 220°C to 250°C, mold temperature 8–20°C, fill time 0.25–0.45 s, hold pressure 45–60 MPa, back pressure 2–5 MPa, and total cycle 4.5–6.5 s. In production-scale lines, insufficient cooling-water turbulence is observed as stacking-ledge dimensional variation, while mold temperatures above 20°C increase demolding flash. Pre-drying is unnecessary below 60% relative humidity; exposed resin held above 60% RH should be dried for 2 h at 70°C to reduce surface splay. Terminal finished forms include 8 oz–32 oz dairy tubs, portion cups, and snap lids.

What Limits Gate Freeze Time in 48- to 96-Cavity Closure Molding?

Closure and overcap production from ALATHON M5372 is dominated by gate-freeze dynamics in valve-gate and tunnel-gate hot-runner systems, where small gate diameters of 0.5–0.8 mm create the primary pressure-drop boundary. If the gate freezes before hold-pressure transfer is complete, the tamper-evident bridge and knurl diameters drift beyond dimensional tolerance; if the gate remains open too long, hot-runner stringing and additional screw recovery time reduce overall equipment effectiveness. Direct food-contact closures require 21 CFR 177.1520(c), EU Regulation (EU) No 10/2011, and manufacturing hygiene under 21 CFR Part 174.5 and EU Regulation 2023/2006. Formula addition typically includes a 5% erucamide slip masterbatch at 1.5–2.5 wt%, a fluoropolymer-free processing aid at 0.2–0.5 wt%, and a food-contact-compatible silicone release additive at 0.1–0.2 wt%; higher erucamide concentrations reduce coefficient of friction but may plate out on mold vents and hot-runner components. Injection molding on 48- to 96-cavity stack tools with 250–500 t clamp force uses melt temperature 215–245°C, hot-runner manifold temperature 220–240°C, mold temperature 10–15°C, hold pressure 35–50 MPa, back pressure 3–8 MPa, and cycle time 3.8–6.0 s depending on cap weight and bridge thickness. A documented production-scale failure mode is vent erosion at the parting line after extended runs above 250,000 cycles; increased flash and reduced gate sealing result. Finished product types include non-carbonated beverage closures, condiment closures, dairy overcaps, and secondary overcaps for cosmetic or pharmaceutical bottles where food-contact clearance is not required. Published data for carbonated soft-drink pressure-retention closures based on M5372 is limited, and such applications require separate CO₂ retention qualification.

Industrial open-head pails, locking lids, and packagings for regulated liquids

When open-head pails are molded for UN-rated transport of viscous liquids, the lower injection pressure requirement of ALATHON M5372 assists in filling thin handle bridges and lid gasket seats without excessive cavity-pressure peaks. Regulatory compliance for dangerous goods packagings is determined by UN Model Regulations Chapter 6.1; removable-head plastic jerricans are commonly classified as packaging code 3H2, while larger open-head plastic drums are 1H2, with performance testing under 49 CFR Part 178 or national equivalents. REACH Regulation (EC) No 1907/2006 Article 33 communication duties apply if SVHC content in the article exceeds 0.1 wt%. The compound addition for outdoor or colored pails includes UV stabilizer masterbatch at 1.0–2.0 wt% and carbon black or color concentrate at 2.0–4.0 wt%; a dual-use food-contact masterbatch is required only for pails marketed into food logistics. Injection molding on 500–900 t presses with accumulator assist or servo pumps uses melt temperature 215–240°C, mold temperature 15–25°C, hold pressure 25–40 MPa, cooling time 18–35 s, and total cycle 35–55 s for a 20 L pail. On production lines, handle bridges are observed as the highest-risk area for sink marks and impact fracture; processors delay gate freeze by enlarging the gate to 7–9 mm and reducing hold-pressure taper. Terminal finished products include 5 L, 10 L, 15 L, and 20 L open-head pails for paints, coatings, chemical concentrates, detergent powders, and water-based emulsions.

Houseware storage products such as stackable totes, drawer dividers, and modular shelf bins are molded from ALATHON M5372 on medium-tonnage injection presses with clamp force 150–350 t, barrel temperature 200–230°C, and mold temperature 10–25°C. The material addition is typically 0.5–2.0 wt% color concentrate and, for outdoor items, 1.0 wt% UV stabilizer concentrate; general-purpose European distribution is assessed under REACH Regulation (EC) No 1907/2006 Annex XVII restricted substance limits, while RoHS Directive 2011/65/EU applies only to electrical or electronic components integrated into the article. This scenario does not include direct food-contact claims; if the storage article is used in food processing environments, compliance with FDA 21 CFR 177.1520(c) and EU Regulation (EU) No 10/2011 requires migration testing on the finished article. Processing is established on cold sprue or tunnel-gate tooling; no pre-drying is required below 60% relative humidity, and the main production-scale defect is flow-line visibility at high melt temperature. Finished types include stackable totes, storage crates, drawer dividers, modular shelf bins, and desk organizers.

When Cosmetic Jars and Overcaps Replace Polypropylene for Environmental Stress-Crack Resistance

Because ester-based solvents and high-pH emulsions generate radial cracking in polypropylene snap fits, cosmetic packaging suppliers evaluate ALATHON M5372 for opaque jars and overcaps that require consistent hoop stress and snap-fit retention. The resin’s narrow molecular-weight distribution supports uniform shrinkage, but it does not provide glass-like clarity; matte and pigmented finishes are the practical design envelope. Regulatory assessment for finished cosmetic packaging in the EU is governed by REACH Regulation (EC) No 1907/2006 Annex XVII restricted substances and the Cosmetic Products Regulation (EC) No 1223/2009 Article 10 safety assessment, which requires packaging interaction to be considered in the product safety report. For dual-use cosmetic food-contact claims, the finished article must also meet 21 CFR 177.1520(c) and EU Regulation (EU) No 10/2011 migration limits. Formulation addition is typically 1.5–2.5 wt% pigmented masterbatch, with matting or pearlescent concentrates added at 1.0–2.0 wt% when specified; migratory slip additives are limited to 0.2–0.5 wt% because exudation can alter cosmetic base texture. Injection molding with polished SPI A-1 cavity surfaces, valve-gate or cold-runner systems, clamp force 150–350 t, melt temperature 220–250°C, mold temperature 15–25°C, and cycle time 20–35 s for wall thickness 1.5–3.0 mm is typical. Production lines using textured cavity surfaces report mold-release inconsistency below 15°C mold temperature; increasing mold temperature to 20–25°C improves snap-fit geometry release. Terminal finished products include opaque jar bodies, secondary overpack shells, compact bases, and overcaps for fragrance pumps.

Aerosol overcaps are not pressure vessels, but their wall stock must survive drop testing

In high-speed aerosol filling lines, overcaps and trigger-sprayer shrouds molded from ALATHON M5372 require dimensional stability on vibratory bowl feeders and rotary capping equipment. The relevant regulatory framework is limited to the EU Aerosol Dispensers Directive 75/324/EEC for the filled can assembly and REACH Regulation (EC) No 1907/2006 for article restrictions; product-specific safety requirements apply at the formula level and do not impose direct migration testing on the overcap. The formulation is generally M5372 at 98.0–99.5 wt% with color masterbatch at 1.0–2.0 wt% and slip agent at 0.2–0.5 wt% to maintain nesting and denesting behavior on automated sorting lines. Injection molding uses clamp force 150–300 t, melt temperature 210–240°C, mold temperature 10–20°C, and cycle time 15–25 s; undercut side actions for aerosol can rim snap geometries require consistent ejection temperatures to prevent white stress marks. In high-speed assembly, a common production failure is outer-diameter ovalization due to uneven mold cooling, which increases jamming rates on rotary cap elevators. Finished types include overcaps for air freshener, shaving foam, spray paint, insecticide, and household trigger-sprayer shrouds.