INEOS Styrolution Luran® S ASA 767KE in Downstream Manufacturing

INEOS Styrolution Luran® S ASA 767KE is an acrylonitrile-styrene-acrylate terpolymer supplied as pellets for injection moulding and extrusion. The downstream sectors below are restricted to applications where the saturated acrylic-ester elastomer phase provides measurable weather resistance relative to ABS and where the required mechanical loads do not demand a flame-retardant polycarbonate blend. Regulatory burden in the European market is governed by REACH 1907/2006 and, for electrical/electronic enclosures, by RoHS Directive 2011/65/EU. The scenarios include compliance test standards, feed ratios, production equipment conditions, and terminal component types. The data are provided as production reference points rather than final-component guarantee; grade-specific certificates and full test reports on finished parts remain the controlling documents.

Unpainted exterior trim components are moulded from 767KE because the acrylic-ester phase tolerates continuous solar load without the chalking or gloss step-change observed in many ABS grades. In visible-surface automotive parts, the pellet feed is maintained at 100 wt% virgin material; spruce and runner regrind is reintroduced at no more than 20 wt% only when clean, unpainted, and processed through a closed-loop desiccant dryer. A carbon black masterbatch is metered at 0.8–1.5 wt% for deep-black parts, while custom exterior colours commonly use 2.0–3.0 wt% of an ASA-compatible colour concentrate. Pre-drying uses a desiccant dryer at 80 °C for 4 h with a dew point not exceeding −30 °C; field defects such as silver streaking and gate blush appear when the dew point rises above −25 °C. Melt temperature at the nozzle is held between 240 °C and 260 °C, with a barrel profile from rear to front of 220/235/245/255 °C. Hot-runner manifold and drop temperatures must not exceed 260 °C, because a 15-minute residence at or above that temperature raises yellowness index by more than 1.5 units and shifts colour on re-melted material. Mould surface temperature is maintained at 60 °C to 80 °C, and injection speed is profiled to prevent jetting on polished steel. Validation follows ISO 527-2 for tensile modulus, ISO 179-1:2023 for notched Charpy impact at 23 °C and −30 °C, and ISO 4892-2:2013 method A cycle 1 for xenon weathering. Acceptance criteria are often set at ΔE < 3.0 and gloss retention greater than 70% after accelerated exposure. Terminal parts made from 767KE include mirror housings, cowl vent grilles, roof ditch mouldings, radiator grille shutters, and wiper arm covers.

What Limits Cap-Layer Thickness Stability When 767KE Runs Over Rigid PVC in Profile Extrusion?

Coextrusion of 767KE as a weather-resistant cap layer over rigid PVC for window and façade lineals is limited less by melt viscosity than by thermal separation between the two polymers and by geometric uniformity of the feedblock. In a profiled coextrusion line, the ASA cap layer is melted in a dedicated single-screw extruder of 32 mm diameter and 30:1 L/D using a barrier screw that keeps melt temperature at 230 °C to 245 °C. The PVC substrate is processed in a counter-rotating twin-screw extruder with barrel temperatures held at 185 °C to 195 °C to avoid HCl evolution. The two melts meet in a coextrusion feedblock or multi-manifold die; the die lip is maintained at 210 °C to 220 °C as a compromise condition. Exceeding 220 °C at the combined melt stream risks incipient degradation of the PVC substrate and loss of fusion, while below 205 °C the ASA layer can exhibit melt fracture and hazing at the surface. A gear pump on the cap-layer extruder reduces pulsation, and cap thickness is controlled between 0.15 mm and 0.25 mm. The cap layer is fed as 100 wt% virgin 767KE; trimmed edge regrind is not returned to the cap layer because the thermal history of ASA edge trim alters flow behaviour and produces pitting. The trim is instead incorporated into the PVC substrate masterbatch at up to 25 wt% only when pulverized to a maximum particle size of 0.4 mm. Haul-off speed is synchronized to die swell through a vacuum calibration tank with water circulation at 15 °C to 20 °C; insufficient cooling causes ripple because the ASA layer solidifies after PVC and shrinks at a different rate. Compliance for lineals includes EN 12608-1:2020 for unplasticized PVC profiles and RAL GZ 716 for quality assurance where applicable. Cap-layer adhesion after weathering is checked by cross-cut methods under ASTM D3330/D3359. Terminal products include window lineals, door profiles, fascia boards, cladding strips, and shutter profiles in grey, brown, or black exterior surfaces that must retain gloss without painting.

Outdoor Electrical Enclosure Moulding and the UL 746C Documentation Requirement

Outdoor telecommunication and utility enclosures are injection-moulded in 767KE when the housing must pass accelerated weathering without painting and must survive site handling at low temperature. The moulding feed is 100 wt% virgin material for first-shot components; closed-loop regrind is limited to 15 wt% in non-load-bearing covers because higher fractions can reduce notched impact at −30 °C below the acceptance threshold. The material is dried to 0.02% residual moisture and processed at a melt temperature of 245 °C with internally heated hot-runner drops to avoid external heating bands that create hot spots. For a typical terminal-box enclosure of 2.5 mm nominal wall, injection pressure is 80–110 MPa, hold pressure is 50–70 MPa, and cooling time is 18–22 s; clamp force is sized to avoid flash on low-draft shut-off ribs, typically 450–600 t. Weathering validation follows ISO 4892-2:2013 with 2,000 h xenon exposure. Outdoor suitability is documented under UL 746C only when the specific colour grade is listed in the UL Yellow Card; an enclosure manufacturer cannot transfer a generic ASA f1 rating without certificate verification. Ingress protection is evaluated by IEC 60529 to IP65 or IP66 depending on the gasket seat design, and mechanical impact is tested by IEC 62262 to IK07 or IK08. The acrylic-ester phase in ASA provides better hydrolysis resistance than impact-modified ABS in condensation-prone enclosures, but the grade is not an inherently V-0 material; enclosures requiring a V-0 classification must use an alternative flame-retarded grade. Components mounted near coastal infrastructure require ISO 4628-3 visual corrosion assessment because UV alone does not account for salt spray action. Terminal products are outdoor telecom splice enclosures, low-voltage distribution boxes, antenna radome brackets, and metering-box covers.

When 767KE Enters a Sanitaryware Moulding Cell, Cleaning-Agent Resistance Rather Than Impact Defines the Reject Criteria

Sanitaryware components moulded in 767KE are exposed to repeated wiping with quaternary ammonium disinfectants, hypochlorite solutions, and low-pH limescale removers. Chemical resistance is assessed by ISO 175:2010 or ASTM D543-20 after 7-day immersion at 23 °C in 10 wt% sodium hypochlorite solution and 5 wt% acetic acid solution; visual whitening and tensile property retention are recorded. In these applications, the material is processed at 100 wt% virgin pellet with 1.0–2.5 wt% white or ceramic-tone masterbatch; regrind from gated parts is allowed up to 20 wt% only where the final surface is textured or semi-gloss, because higher regrind can create weld-line opacity variations. Injection moulding is performed with polished cavity surfaces and sequential valve gating; melt temperature is 240–255 °C, mould temperature is 60–75 °C, and post-mould holding time is 8–12 s before ejection to avoid deformation of thin ribs around the seat hinge. Dimensional stability after repeated hot-water exposure is checked by ISO 75-2, and notched impact is verified by ISO 179-1. Because ASA is not a barrier polymer, prolonged contact with ketone-containing cleaners is outside operational limits; use of MEK or acetone for cleaning is not recommended. The grade is not certified as a food-contact material under FDA 21 CFR 177, and it should not be used for potable-water contact or direct food-contact surfaces without separate regulatory confirmation. Terminal products include toilet seat shells, bidet covers, spa access skirts, and bath panel trims.

Garden Equipment Engine Cowls: Injection-Moulded Surface Class and Warpage Control

Garden equipment engine cowls and clamshell housings are moulded from unfilled 767KE to obtain a glossy UV-stable surface without painting. The formulation uses 100 wt% virgin material with 10–15 wt% clean regrind; glass fibre is not added because it would reduce surface gloss and increase tool wear. Melt temperature is 240–250 °C and mould temperature is 60–70 °C. Warpage on large cowls is controlled by balanced runner sizing and uniform cooling; ISO 291 conditioning for 48 h at 23 °C / 50% RH is applied before dimensional checks. Weathering is tested by ISO 4892-2, and low-temperature impact is verified by ISO 179-1 at −20 °C. Terminal products are lawn-tractor hoods, generator access panels, and grass-trimmer clamshells.

Extruded sheet produced from 767KE is converted into thermoformed spa panels, pool step risers, and marine interior fascia where chemical resistance and low-temperature impact are required during installation. Sheet extrusion uses a single-screw extruder with a melt temperature of 235 °C to 250 °C, a three-roll polishing stack with roll temperatures at 75 °C to 85 °C, and sheet thickness from 2.0 mm to 4.5 mm. The feed is 100 wt% virgin resin plus 5–15 wt% edge-trim regrind, with trim reintroduced only after granulation to 6 mm flake and drying to 0.02% moisture. Thermoforming uses plug-assisted vacuum forming with sheet surface temperature at 150–170 °C; below this range the sheet lacks elongation, and above it the surface can develop spider-webbed thinning at corners. Compliance for the formed part includes ISO 179-1 notched impact, ISO 4892-2 for accelerated weathering, and ISO 1133-1:2022 for melt flow rate after drying to confirm no hydrolytic degradation during reprocessing. Terminal products include above-ground pool top rails, hot-tub access panels, and marine locker liners.