LG Chem ABS NS-1610 is an unfilled acrylonitrile-butadiene-styrene injection-moulding grade classified within the styrenic copolymer family referenced by ISO 2580-1:2002. The designation identifies a pelletised compound intended for high-gloss and electroplatable exterior parts, where the melt must fill thin-wall or medium-flow-length cavities without sacrificing the notched-impact strength required for demoulding and service. It is processed on conventional reciprocating-screw injection moulding machines with a general-purpose ABS screw geometry. The grade is differentiated from LG Chem high-impact and high-heat ABS products by a controlled balance between melt volume-flow rate, rubber-phase particle size distribution, and surface etch response in electroplating lines.

Material property declarations for NS-1610 are customarily expressed through the following test matrix: density by ISO 1183-1, melt volume-flow rate by ISO 1133-1 at 220 °C under 10 kg, tensile properties by ISO 527-2, flexural modulus by ISO 178, and notched Izod impact by ISO 180. Publicly available datasheets typically report density of 1.04 g/cm³, melt volume-flow rate in the 20–30 cm³/10 min band, tensile yield stress in the 40–45 MPa band, and notched Izod impact at 23 °C in the 25–35 kJ/m² band. Lot-specific values are supplied in the certificate of analysis and should be used for production validation because third-party datasheets may not reflect the current production campaign.

Drying and Melt-Temperature Boundaries on Injection Lines

Absorption of atmospheric moisture by ABS granules is low in absolute terms but operationally significant because trapped water hydrolyses residual nitrile groups and contributes to silver-streak defects. The resin should be dried in a desiccant hopper dryer delivering −40 °C dew point until the residual moisture content is below 0.1 wt% by ISO 15512. A dryer set point of 80 °C for 2–4 h is standard for the ABS family. At ambient relative humidity above 60%, open storage bins should be avoided; hopper loading from foil-lined bulk containers is recommended. The melt should be maintained between 210 °C and 240 °C. Settings above 250 °C accelerate polybutadiene thermal oxidation and shift the ABS yellowness index.

After drying, the material should be conveyed by a closed vacuum loader or dry-air hopper loader. Long open-air transfer paths allow moisture re-absorption within 30–60 min when ambient humidity exceeds 60%; dry-air hopper storage is preferred for production runs longer than one shift. If the moulded part shows splay or turbulence marks, the drying dew point should be checked before raising melt temperature, because excessive melt temperature lowers melt strength and increases gas evolution from degraded butadiene.

On a production line, the practical difference between NS-1610 and a lower-flow general-purpose ABS appears in nozzle pressure drop and part-weight consistency. When NS-1610 is run in the same tool, peak injection pressure at the screw tip commonly decreases, allowing the process to operate further from the machine’s hydraulic pressure limit. The screw cushion should still be maintained between 2 mm and 5 mm to provide consistent hold-pressure transmission; if the cushion is consumed, the non-return valve leaks and shot-to-shot weight variation increases. Cavity pressure transducers located after the gate are used to switch from velocity-controlled filling to pressure-controlled packing at a set value, typically 30–50 MPa for unfilled ABS, depending on wall thickness. Gate freeze pressure is recorded as a lot-specific quality marker and should be correlated with moulded-part weight.

Melt flow length in thin-wall sections is best verified with a spiral-flow tool having channel depth of 1.5 mm and channel width of 6 mm; the absolute spiral length is machine- and tool-dependent, so it should be used as a relative run-to-run check rather than a material absolute specification. In injection moulding of electroplatable parts, mould-filling analysis should keep gate shear rate below 100,000 s⁻¹ to avoid rubber-particle orientation that reduces electroplating peel strength. After switchover, packing pressure is held until the gate freezes. Premature gate freeze traps internal pressure and increases warpage; late gate freeze extends cycle time and creates gate blush. Direct edge gates with depths of 50% to 70% of the part wall thickness and land lengths of 0.5–1.0 mm are used for visible ABS parts. Linear moulding shrinkage is typically 0.4% to 0.7% when measured by ISO 294-4; flat electroplating surfaces require cavity-side and core-side mould-temperature balance within ±5 °C. Differential cooling across a rib boss produces sink marks and plateable surface distortion.

What Distinguishes NS-1610 from High-Impact and High-Heat ABS Grades?

Within LG Chem’s styrenic portfolio, high-impact ABS grades are optimized for maximum notched impact by increasing rubber volume or adjusting rubber particle size distribution. The cost is lower melt flow and longer cooling-controlled cycle time. High-heat ABS grades use additional comonomers or imide structures to lift heat deflection temperature above standard ABS, but that raises melt viscosity and can narrow the moulding window. NS-1610 occupies an intermediate position: the melt volume-flow rate is intentionally raised for short filling time in large-area or thin-wall parts, while the rubber-phase morphology is retained for electroplating etch and low-temperature ductility. The effect is not simply a viscosity change. In high-impact grades, the rubber phase is enlarged or broadened in particle size distribution to create shear yielding; that also creates a more pronounced plateau in the melt elasticity curve, which can alter gate frost and die swell. NS-1610 is tuned for flatter cavity pressure decay after switchover, which helps electroplated parts retain dimensional stability when plating racks apply tensile loads. In high-heat ABS, the heat distortion property is obtained by replacing part of the styrene with α-methylstyrene or maleimide; those units reduce chain mobility and require higher melt temperature, but they also change the UV and thermal ageing profile. Published quantitative comparisons among these grades are limited; substitution of NS-1610 for a high-impact or high-heat grade should be verified with side-by-side spiral-flow, drop-weight, and plateable-peel tests.

Electroplating lines for ABS typically etch the moulded surface with a chromic acid/sulfuric acid mixture to produce microholes that absorb the palladium-tin catalyst. NS-1610 is formulated to respond to this etch with uniform surface roughness that promotes mechanical interlock between the metal layer and polymer. Moulders should avoid weld lines in visible plated surfaces because the weld region has altered rubber orientation and may show lower local peel strength after plating; gate location should produce one flow front or place weld lines on non-appearance edges. Adhesion is measured by ASTM B533 peel testing. If the part design requires through-holes or ribs on the plating face, the depth-to-width ratio should be controlled to reduce jetting; jetting produces a surface skin with low etch uniformity. Plating rack contact on exterior surfaces should be placed on non-aesthetic edges. The high current density at exposed corners can produce burnt deposits; moulded-in radii of 0.5 mm or larger reduce current-density concentration. The etched surface should be free of release agents containing silicones; silicone transfer prevents catalyst absorption and produces skip-plating. Mould release agent use should be eliminated for plating grades; if a release aid is required, it must be chemically removed before etch.

If Regrind Fractions Exceed 20% in Closed-Loop Moulding

Regrind of NS-1610 from hot-runner sprues and runners may be re-introduced into the feed stream; however, each heat history reduces polybutadiene crosslink density by shear and oxidation, so melt volume-flow rate rises and notched Izod impact falls. Production controls should limit regrind content to 20 wt% unless the moulded part is non-critical. Above 30 wt%, a drop in Charpy or Izod impact should be quantified by ISO 179-1 or ISO 180. In electroplating applications, regrind above 15 wt% may produce inconsistent etch rates because the butadiene phase is degraded preferentially; this can shift peel adhesion tested under ASTM B533 and create skip-plating or adhesion failure. Blending regrind with virgin material should be done with gravimetric batch blenders with accuracy within ±0.5 wt%. Incoming material control should include melt flow rate as a first-line verification. If measured MFR deviates more than ±10% from the certificate of analysis, the material should be dried and re-tested before use. Density and ash checks under ISO 1183-1 and ISO 3451-1 are useful for detecting cross-contamination with filled or flame-retardant grades. Storage should be in covered, low-humidity conditions at 10–30 °C; pellets supplied in 25 kg sacks or octabins should not be exposed to direct sunlight for prolonged periods.

Solvent Wiping Is Not a Benign Surface Treatment

NS-1610 moulded surfaces accept two-component acrylic or polyurethane topcoats after removal of external release agents or fingerprint oils. Adhesion can be verified by cross-cut testing under ISO 2409 or pull-off testing under ISO 4624. Solvent wiping should be restricted to isopropanol, ethanol/water blends, or aliphatic hydrocarbon-based cleaners; ketones and aromatic hydrocarbon solvents can induce environmental stress cracking. Flame or corona pre-treatment is not usually required for ABS paint adhesion; however, plasma treatment can raise surface energy from 38 mN/m to 50 mN/m before bonding. Adhesives based on cyanoacrylate, polyurethane, or acrylic are used; cyanoacrylate can cause stress cracking in some ABS grades, so compatibility testing under ISO 22088-2 is required. Continuous service temperature for standard ABS is generally below 80 °C; NS-1610 is not selected for under-hood thermal exposure above the Vicat threshold. Parts exposed to elevated temperatures should be evaluated by heat deflection test under ISO 75-2; standard unfilled ABS values often fall in the 85–100 °C range at 1.8 MPa. The grade is not intrinsically flame retardant; if a UL 94 V-0 rating is needed, a flame-retardant ABS or PC/ABS should be selected instead of NS-1610.

Regulatory documentation accompanies each commercial shipment. Shipments of NS-1610 are accompanied by a certificate of analysis that records batch-specific melt volume-flow rate and mechanical values. The base ABS resin can be evaluated under 21 CFR 177.1020, but final food-contact articles must comply with applicable migration limits under Regulation (EU) No 10/2011. The grade is not supplied with an implicit food-contact clearance; additive package and regrind content can change migration behavior. Users should request food-contact certification from LG Chem before using NS-1610 in food-contact articles.