Lotte Chemical Starex ABS VE-0857 is an acrylonitrile-butadiene-styrene copolymer assigned to the sheet and profile extrusion segment of the supplier’s portfolio. The grade is not classified as a high-flow injection-moulding resin; its published melt volume-flow rate of 8 cm³/10 min under ISO 1133-1:2022 at 220 °C with 10 kg is deliberately moderate to maintain melt strength during sag-controlled sheet forming. The nominal density is 1.04 g/cm³ under ISO 1183-1:2019. In extrusion plants, VE-0857 is typically processed after desiccant drying to a residual moisture ceiling of 0.05 wt%; above that ceiling, sheet surfaces show silver streaking, bubbles, and reduced notched impact strength in the formed part. The grade is specified for refrigerator inner liners, sanitary-ware sheet, luggage shells, and automotive interior panels where moderate heat resistance and deep-draw formability are required. These applications are shape-forming operations rather than thin-wall injection moulding.

Material property comparisons must be read against specimen geometry and conditioning state. Supplier technical literature reports mechanical data on ISO 527-1A tensile bars and ISO 178 flexural bars conditioned at 23 °C and 50 % RH for 48 h. North American ASTM values are not interchangeable unless the same specimen thickness, notch radius, and strain rate are used. Where a specific production configuration lacks published data, that limitation is stated in this document rather than extrapolated from unrelated ABS grades.

What Property Data Define VE-0857 as an Extrusion Grade?

These values are typical injection-moulded or compression-moulded specimen data, not guaranteed lot minima. The notched Izod value reflects the method 1A notch configuration; Charpy values under ISO 179-1:2010 may not be directly interchangeable. For sheet extrusion, the relevant property shifted away from standard tensile or flexural response toward low-shear melt strength, extensional viscosity at thermoforming temperature, and sag resistance. Those values are not captured by room-temperature flexural modulus or notched impact testing.

On production-scale single-screw extruders with L/D ratios between 24:1 and 32:1, VE-0857 requires pre-drying at 80 °C to 90 °C for 3 h to 4 h in a desiccant dryer with a dew point below −30 °C. This is not optional when ambient humidity exceeds 60 % RH. The barrel profile is normally set from 190 °C at the feed section to 220 °C at the metering section, with the die held at 210 °C to 230 °C. No melt zone should be operated above 250 °C; thermal degradation in ABS liberates styrene and acrylonitrile oligomers, shifts the colour toward yellow, and reduces notched Izod impact strength. A breaker plate with 60/90/60 mesh screen pack is common for foreign-material control; pressure drop across the pack should not exceed 15 MPa or the effective melt temperature rises by shear heating.

The extruded sheet is usually cooled on a three-roll stack with the middle roll held at 80 °C to 95 °C. The top and bottom roll temperatures are adjusted according to sheet thickness and surface finish; polished chrome rolls produce gloss, whereas matte rolls require a surface-treated Release coating. Sheet thickness below 1.5 mm demands tighter die-lip parallelism and a vacuum calibration tank. For thermoforming, the sheet surface temperature is normally between 130 °C and 160 °C. At draw ratios above 1.5:1, temperature variation across the sheet should be held to ±5 °C; wider variation creates webbing, stress whitening, or blown corner radii.

Melt Rheology and Die-Swell Control in Sheet Extrusion

VE-0857 is not optimised for spiral-flow capability in thin-wall injection moulding. Its lower melt volume-flow rate is a rheological constraint: the grade must sustain a stable sheet web at low shear rates without excessive sag. In sheet extrusion, this property is observed as higher die-swell ratio and better extensional viscosity than high-flow ABS grades. Capillary rheometry data for this specific grade are not fully disclosed in the supplier technical leaflet; published data for this specific configuration is limited. However, the difference from high-flow injection ABS is visible on a production line. VE-0857 tolerates a wider die-lip opening before edge bead instability occurs, and it resists draw resonance at take-off speeds above 12 m/min on a 1000 mm coat-hanger die. The draw-resonance onset remains dependent on die gap, roll temperature, and sheet gauge.

Processors switching from high-flow ABS to VE-0857 in sheet production typically observe an increase in head pressure at the same screw speed. If head pressure exceeds 35 MPa, the melt temperature can surpass the 240 °C ceiling even when the barrel setpoint is lower. Screw speed should be reduced, or a barrier screw with lower shear-heating design should be selected. Vent port temperatures should remain between 180 °C and 200 °C to avoid feeding melted particles into the vacuum system. Failure modes recorded on production equipment include plate-out on chrome rolls from low-molecular-weight fractions, burned speck formation after 6 h of continuous operation without purging, and gauge bands from uneven die-lip heater response.

When VE-0857 Replaces High-Flow Injection Moulding ABS or Impact-Modified Polystyrene

In substitution work, VE-0857 is selected when the process is not injection moulding but sheet extrusion, vacuum forming, or pressure forming. Replacing a high-flow injection ABS with VE-0857 in thin-wall injection moulding is not advisable for wall sections below 1.2 mm; the lower melt volume-flow rate produces short shots or requires melt temperatures above the 240 °C upper limit. The injection-moulding press clamp force requirement may also rise because the lower flow increases filling pressure. The use of VE-0857 is therefore restricted to extrusion-adjacent processes.

When compared with high-impact polystyrene, VE-0857 exhibits a higher Vicat softening temperature of 98 °C versus the 85 °C to 90 °C range typical of HIPS, and a higher flexural modulus of 2100 MPa versus 1400 MPa to 1800 MPa for many HIPS grades. It also offers better resistance to aliphatic hydrocarbons in ASTM D543-21 immersion screening at 23 °C for 24 h; published data for this specific VE-0857 configuration is limited for quantitative retention. The ABS grade is more sensitive to oxidative yellowing in unpainted outdoor exposure than many HIPS materials. HIPS can be processed without desiccant drying in many plants, whereas VE-0857 requires the drying protocol described above. This operational boundary is a significant conversion cost when an existing HIPS line lacks a desiccant dryer.

Distinguishing VE-0857 from Flame-Retardant ABS and PC/ABS Blends

VE-0857 is a non-flame-retardant ABS with a UL 94 rating of HB at 1.5 mm to 3.0 mm. It does not contain the brominated flame-retardant package used in V-0 ABS grades, which typically raises density to 1.16 g/cm³ to 1.20 g/cm³ and reduces thermal stability during residence time in the barrel. For electrical enclosures or conformal appliques requiring V-0 at 1.5 mm, VE-0857 is unsuitable; a V-series grade or PC/ABS alloy should be verified against IEC 60695-2-11 glow-wire requirements. The lower density of VE-0857 gives a mass yield advantage of approximately 10 % to 13 % per unit volume when compared with many flame-retardant ABS grades, but that is a conversion consideration rather than a mechanical property statement.

Compared with PC/ABS blends, VE-0857 has lower heat resistance and lower tensile strength, but it is less shear-sensitive and does not require the same melt-temperature precision. PC/ABS blends may have heat deflection temperatures above 100 °C at 1.8 MPa, while VE-0857 is reported at 87 °C under the same condition. In thermoforming, the ABS grade can be processed at lower sheet temperatures, which reduces energy input and sag; however, the final part will also have a lower service-temperature ceiling. Any claim of chemical resistance must be qualified by chemical class. VE-0857 is not resistant to aromatic hydrocarbons, ketones, esters, or chlorinated solvents. Stress-cracking tests under a constant strain of 0.5 % are recommended for applications involving cleaning agents or adhesives.

Application trials on deep-draw thermoforming machines should start with a sheet temperature of 145 °C and a plug-assist speed of 800 mm/s to 1000 mm/s. The plug material influences wall-thickness distribution; syntactic foam or PEEK-coated plugs reduce chilling at the contact surface. During ambient storage, VE-0857 pellets should remain sealed until use because moisture regain from 60 % RH air can exceed the 0.05 wt% moisture ceiling in less than 2 h, depending on pellet temperature and airflow. Silo storage with heated air is not a substitute for desiccant drying.

Unprotected outdoor exposure of VE-0857 is limited by UV-induced yellowing and surface erosion. Carbon black loading of 2 phr to 3 phr or a coextruded cap layer is required for external automotive or building components. Where colour stability under ISO 4892-2:2013 weathering is specified, accelerated test data must be generated on the actual pigment formulation because colorants influence the degradation kinetics of the styrene-acrylonitrile phase.

Process shutdowns longer than 15 min require purging with general-purpose ABS or acrylic and reducing barrel temperatures to 180 °C. Discoloured resin remaining in the die or screen pack should be removed before restart. These operating boundaries are derived from standard ABS extrusion practice, and lot-specific adjustments must be validated with the supplier’s certificate of analysis.