Dongguan Shengtai PC/ABS HG2300 is a polycarbonate/acrylonitrile-butadiene-styrene blend supplied as pelletised feedstock for injection moulding and extrusion. The grade designation HG2300 identifies a medium-flow PC/ABS alloy intended for technical components in which the dimensional stability and heat resistance of polycarbonate are combined with the lower melt viscosity and lower material cost of ABS. The compound is specified for electrical enclosures, appliance housings, automotive interior trim substrates, thin-wall electronic device housings and medical equipment enclosures where a balance of stiffness, impact resistance and flame-retardant capability is required. Published data for this specific configuration is limited; the property windows cited in this document are representative of PC/ABS grades in the same flow and impact class and remain subordinate to lot-specific certificates of analysis from Dongguan Shengtai. The blend is produced by melt compounding under controlled moisture conditions, and it is supplied with residual moisture below the threshold at which hydrolysis of the polycarbonate phase becomes significant during melt processing. Before production release, processing personnel should confirm drying, melt-temperature and mould-temperature parameters against the current technical datasheet.

How does the HG2300 specification align with ISO 1133-1:2022 and ISO 527-2?

Characterisation of HG2300 follows standardised ISO and ASTM procedures. Density is measured according to ISO 1183-1:2019 or ASTM D792-20; values for this family typically range from 1.12 g/cm³ to 1.16 g/cm³. Melt volume-flow rate is determined at 260 °C with a 5.0 kg piston load under ISO 1133-1:2022; the medium-flow designation usually corresponds to a melt volume-flow rate of 10 cm³/10 min to 20 cm³/10 min. Tensile properties are tested on Type 1A specimens using ISO 527-2/1A/50 at 50 mm/min. Tensile stress at yield is generally recorded between 50 MPa and 60 MPa, with elongation at yield between 3 % and 5 % and elongation at break above 50 %. Flexural modulus according to ISO 178 at 2 mm/min typically falls between 2,200 MPa and 2,600 MPa. Notched Izod impact strength tested under ISO 180/1A at 23 °C is commonly reported between 45 kJ/m² and 60 kJ/m², with low-temperature values at -30 °C between 30 kJ/m² and 45 kJ/m². Heat deflection temperature under ISO 75-2/B at 0.45 MPa stress is usually 110 °C to 120 °C; under ISO 75-2/A at 1.8 MPa stress, values are lower, commonly 100 °C to 110 °C. Flammability classification under UL 94 may be V-0 at 1.5 mm thickness for flame-retarded versions; non-flame-retarded versions may be HB. Because colorants and regrind can shift flammability, each lot should be tested according to UL 94 vertical burn protocols with the actual colour and regrind content.

Moisture control is the first boundary condition for HG2300. Because the polycarbonate phase undergoes hydrolysis at melt temperatures above 270 °C when residual moisture exceeds 0.02 %, the compound is dried in dehumidifying dryers at 80 °C to 100 °C for 2 h to 4 h until the drying-air dew point is maintained at -30 °C or lower. Over-drying above 110 °C for periods longer than 6 h can produce a visible yellow shift and reduce notched Izod impact by 5 % to 10 % in moulded specimens. Production-scale observations on a corotating twin-screw extruder with an L/D ratio of 40:1 indicate that screw speeds between 250 rpm and 350 rpm and barrel temperatures in zones 4 through 8 of 240 °C to 260 °C are adequate for dispersion without exceeding the degradation threshold. If the melt temperature exceeds 280 °C, polycarbonate chain scission and ABS rubber-phase oxidation produce black specks and a loss of impact toughness. Injection moulding machines with clamp forces of 800 kN to 12,000 kN are used depending on projected area and wall thickness; the shot size should be 30 % to 70 % of barrel capacity for residence-time control. The absolute maximum residence time at melt temperature should not exceed 8 min to 10 min.

Injection moulding conditions and gate freeze constraints

The melt temperature for HG2300 is maintained at 240 °C to 270 °C, measured at the nozzle with a needle pyrometer after stable cycling. Mould temperature is typically set at 60 °C to 90 °C. Mould temperatures below 50 °C reduce weld-line strength and produce visible flow lines in dark colours; mould temperatures above 100 °C extend cycle time and increase plate-out risk for certain flame-retardant packages. Injection velocity should be profiled to avoid shear heating above 1,000 s⁻¹ in the gate area; gate shear rates above 50,000 s⁻¹ may cause surface delamination and free-radical degradation of the butadiene phase. Gate geometry should provide a land length of 0.5 mm to 1.0 mm, and the gate diameter should be 40 % to 60 % of the wall thickness. Gate freeze time at 80 °C mould temperature is approximately 1 s to 2 s per millimetre of wall thickness; hold pressure should be maintained until the gate seals. Packing pressure is typically 40 MPa to 60 MPa hydraulic, with switch-over from velocity to pressure control at 95 % to 98 % of volumetric filling. Weld lines in complex electrical housings can be minimised by placing gates at the thickest section and using sequential valve gates where surface aesthetics are critical.

Tool design exerts a measurable effect on the mechanical performance of HG2300. Sharp internal corners should be radiussed at 0.5 mm to 1.0 mm to avoid notch stress concentrations. Wall-thickness transitions should be designed with a taper of 1° to 2° per side and a nominal wall of 1.0 mm to 2.5 mm for thin-wall electrical enclosures. Thicker sections above 4.0 mm may develop sink marks and voiding unless packing pressure is increased and cooling time is extended. Rib thickness should not exceed 60 % of the adjacent wall thickness. Ejection pins should be placed away from gate vestige areas where molecular orientation is highest. In production, dimensional stability is evaluated by measuring shrinkage after 24 h conditioning at 23 °C and 50 % relative humidity; typical mould shrinkage for PC/ABS is 0.4 % to 0.7 % in the flow direction and 0.5 % to 0.8 % across flow, but tool-specific measurements should be used for cavity dimensions.

When unfilled PC or standard ABS is replaced by HG2300

The substitution of HG2300 for unfilled polycarbonate or standard ABS involves a shift in property profile rather than a direct one-to-one exchange. In unfilled PC, heat deflection temperature is higher and low-temperature impact is superior, but melt viscosity is elevated and the material is more sensitive to moisture and stress cracking. HG2300 reduces injection pressure and melt temperature by 20 °C to 30 °C compared with unfilled PC, and it lowers part density from approximately 1.20 g/cm³ to 1.14 g/cm³. Against standard ABS, HG2300 increases heat deflection temperature by 15 °C to 30 °C and raises notched Izod impact at low temperatures, but it also increases melt temperature and drying requirements. The coefficient of linear thermal expansion for PC/ABS is usually between 60 µm/m·°C and 80 µm/m·°C, compared with 80 µm/m·°C to 100 µm/m·°C for ABS; this narrower expansion window reduces gap changes in multi-component assemblies. Electrical properties such as comparative tracking index may be evaluated under IEC 60112; values for PC/ABS grades of this type are often reported between 250 V and 400 V, but the exact value depends on the flame-retardant system.

Regulatory screening for HG2300 should be conducted before application release. Candidate compounds are typically screened under RoHS Recast (EU) 2015/863 Annex II restrictions for lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls and polybrominated diphenyl ethers, and under REACH Regulation (EC) No 1907/2006 for Substances of Very High Concern in the relevant concentration thresholds. For medical or food-contact applications, additional migration testing under EU 10/2011 or FDA 21 CFR is required; the base polymer system does not automatically confer compliance. The material should not be combined with acetal, PVC or certain thermoplastic elastomers in hot-runner systems or screw recovery without full purging, because incompatible residues can create acids that catalyse PC degradation. Amine-containing additives should be avoided at melt temperatures above 270 °C because they can accelerate polycarbonate hydrolysis. Regrind levels above 30 % may reduce impact strength and increase colour deviation; any regrind must be dried to the same moisture specification as virgin resin and blended in a controlled ratio. The processing window narrows when wall thickness falls below 1.2 mm, requiring elevated melt temperatures and higher injection velocities that may exceed the recommended shear limits; published data for this specific configuration is limited, and process validation should be conducted on the intended tool rather than extrapolated from laboratory specimens.