Commercial designation Guangzhou Keyuan New Material PC/ABS 9300MF refers to a polycarbonate/acrylonitrile-butadiene-styrene alloy supplied in pellet form for injection moulding and extrusion compounding. The grade is positioned within medium-flow PC/ABS systems in which the polycarbonate phase is modified with styrene-acrylonitrile copolymer and an impact-modifying butadiene-containing phase to balance heat distortion, impact resistance, and melt processability. Manufacturer-published datasheet values for 9300MF are not independently reproduced in this document. Where numerical ranges are given, they represent typical property windows reported in open polymer databases and technical datasheets for unfilled PC/ABS alloys of comparable flow class. Suffix nomenclature such as MF is not standardized across suppliers and may denote medium flow, mineral-filled, or an internal grade sequence; the supplier documentation must be consulted for the definitive specification.

In commercial injection moulding, 9300MF is typically selected when a part design requires a lower melt viscosity than low-flow PC/ABS but cannot accept the greater mechanical-property loss associated with very high-flow grades. The material is not a flame-retardant compound unless the supplier documentation contains a UL yellow card and a specific V-0 or V-1 rating; unmodified PC/ABS of this class is commonly rated HB at 1.5 mm under UL 94. The product’s practical utility depends on drying discipline, mould-temperature control, and gate location because the polycarbonate phase is sensitive to moisture-induced chain scission and the SAN phase controls moulded-in stress.

Which Property Targets Distinguish Medium-Flow PC/ABS 9300MF from Low-Flow Formulations?

For a medium-flow PC/ABS of the 9300MF designation, the melt volume-flow rate measured at 260°C and 5 kg according to ISO 1133-1:2022 typically falls between 18 cm³/10 min and 32 cm³/10 min. This window is higher than low-flow impact-modified grades, which commonly run below 12 cm³/10 min, and lower than very high-flow grades that exceed 40 cm³/10 min. Tensile yield strength at 23°C by ISO 527-2:2012 is normally 52–62 MPa, and flexural modulus by ISO 178 is 2,300–2,700 MPa. Notched Izod impact resistance by ISO 180/A at 23°C is commonly 35–55 kJ/m²; at -30°C the same property may fall to 10–20 kJ/m², which is relevant for cold-climate enclosures.

Heat deflection temperature under 1.8 MPa by ISO 75-2 is usually 105–120°C, and density measured by ISO 1183-1 at 23°C lies in the 1.12–1.16 g/cm³ range. Mould shrinkage according to ISO 294-4 is typically 0.4–0.7%, although actual shrinkage depends on glass-fibre content, wall thickness, and gate geometry. Tensile elongation at break by ISO 527-2:2012 is commonly 20–40%, and Vicat softening temperature B50 by ISO 306 is typically 120–135°C. The linear coefficient of thermal expansion by ISO 11359-2 is normally 65–80 µm/m·°C in the flow direction and 70–85 µm/m·°C transverse to flow.

Electrical properties are grade-dependent but unfilled PC/ABS of this class commonly shows volume resistivity above 10¹⁵ Ω·cm by IEC 62631-3-1, surface resistivity above 10¹⁴ Ω, and dielectric strength of 20–30 kV/mm by IEC 60243-1. Comparative tracking index by IEC 60112 for unfilled PC/ABS is commonly 175–250 V. These values should not be used for primary-circuit insulation without grade-specific verification because conductive additives, moisture uptake, or surface contamination can reduce tracking resistance.

Unless a flame-retardant package is explicitly declared, unfilled PC/ABS of this class is generally rated HB at 1.5 mm under UL 94. Applications requiring V-0 at 1.5 mm or glow-wire ignition temperature above 750°C per IEC 60695-2-12 should not assume that 9300MF will meet those requirements without a supplier yellow card.

Injection moulding of Guangzhou Keyuan New Material PC/ABS 9300MF begins with moisture control. Pellets are dried in a dehumidifying dryer at 80–100°C for 3–4 h; when ambient relative humidity exceeds 60%, drying time is extended to 4–6 h and the drying-air dew point is maintained below -30°C. Residual moisture above approximately 0.02% produces splay, silver streaks, and molecular-weight loss at the barrel. Barrel temperature is profiled from 240°C near the feed throat to 270–280°C at the nozzle, with an absolute melt-temperature ceiling of 300°C. Residence time at melt temperatures above 280°C should not exceed 5 min; longer residence or hot-spot zones can cause polycarbonate chain scission, brown streaks, and intermittent nozzle blockage. Mould temperature is controlled between 60°C and 90°C to balance surface finish, weld-line strength, and cycle time. Lower mould temperatures shorten cycle time but increase moulded-in stress and reduce flow length in thin ribs.

On production-scale injection moulding machines with clamp force capacities of 800–1,600 kN for typical enclosure parts, screw-tip injection pressure is usually 80–120 MPa, while hydraulic back pressure is held at 3–7 MPa to maintain melt-density consistency. Screw speed in recovery is 40–80 rpm, and shot size is maintained between 30% and 70% of barrel capacity to avoid long residence time. Venting of 0.02–0.05 mm near the end of fill is used to prevent burn marks. Gate size and location are more critical for 9300MF than for low-flow grades because the medium-flow rheology can create high shear rates at narrow restrictions; side-gate thickness should generally be at least 60–70% of the nominal wall thickness, and valve-gate diameters of 1.0–1.5 mm are typical for thin-wall housings.

When Thin-Wall Electronic Housings Require Balanced Flow and Impact Retention

9300MF-class materials are specified for thin-wall electronics enclosures, router housings, and portable-device bottom cases where wall thickness is below 1.5 mm and the flow-path-to-thickness ratio exceeds 150:1. The medium-flow melt volume-flow rate permits fill times of 0.5–1.5 s on hot-runner tools, while retaining notched Izod impact sufficient for unpackaged drop tests based on IEC 60068-2-27 shock-test methods. Weld lines in such enclosures are a practical failure mode: at the meeting front, polycarbonate and SAN orientation can produce a V-notch effect. Increasing mould temperature to 80–90°C and locating the gate so that weld lines form in low-stress areas are standard corrective actions.

In automotive interior brackets, glove-box components, and centre-console trim, the product is used where heat deflection under 1.8 MPa must remain above 100°C and dimensional stability after 24 h at 90°C is required. For these applications, odour and fogging behaviour must be verified according to VDA 270 or OEM-specific methods, because PC/ABS compounds can release volatile processing aids and low-molecular-weight SAN fractions. Unfilled PC/ABS without UV stabilization is not suitable for direct sunlight without painting, film lamination, or the addition of light stabilizers; yellowing can occur before 500 h of xenon-arc exposure per ISO 4892-2, although published data for this specific product is limited.

The difference from a low-flow PC/ABS is primarily rheological and mechanical. A low-flow grade may show higher notched Izod, but it requires higher melt and mould temperatures and may short-shot ribs or thin bosses. A very high-flow grade may fill thinner walls but can lose 20–30% of notched impact and reduce heat deflection temperature by 5–10°C due to lower polycarbonate content or lower molecular weight. Flame-retardant PC/ABS containing phosphate esters such as resorcinol bis(diphenyl phosphate) can achieve V-0 at 1.5 mm, but often shows greater notch sensitivity, lower tensile strength at elevated temperature, and higher mould deposit potential. Compared with PC/PBT alloys, PC/ABS 9300MF generally has lower continuous-use temperature in aggressive chemical environments but better low-temperature impact resistance and lower shrinkage anisotropy. PC/PBT can exhibit mould shrinkage of 0.8–1.2% in the flow direction, whereas PC/ABS typically remains at 0.4–0.7%, reducing warpage in large flat panels. The table below compares typical property windows across these material classes; values are general industry ranges, not manufacturer guarantees for 9300MF.

Formulation Controls and Compounding Variables in Medium-Flow PC/ABS Production

Batch-to-batch consistency in 9300MF is controlled at the compounding stage. Twin-screw extruders with L/D ratios of 40:1 to 52:1 are used to disperse the SAN phase, polycarbonate, and impact modifier. Screw speeds of 400–800 rpm and specific mechanical energy inputs of 0.20–0.32 kWh/kg are typical for medium-flow PC/ABS; lower energy input can produce coarse polycarbonate domains and lower notched impact, while excessive energy input can raise melt temperature and reduce molecular weight. Vacuum devolatilization at -0.08 MPa absolute or better removes residual styrene and moisture; inadequate vacuum or worn screw elements can generate black specks from material stagnation. Pellet MVR, pellet bulk density, and colour are monitored as release indicators. Drift of ±5% in MVR is commonly considered actionable in injection moulding operations that use automated shot-weight correction or cavity-pressure control.

Incompatibility boundaries for 9300MF-class materials include prolonged contact with ketones, aromatic hydrocarbons, and strong alkaline cleaning agents, which can induce environmental stress cracking. Stress-crack resistance is assessed by ISO 22088-2 or equivalent bent-strip tests. Amine-based mould-release additives and some phosphite stabilizers should be avoided at elevated residence times because transesterification or decomposition can occur at the polycarbonate interface. When regrind is used, the proportion is typically limited to 20–30% by weight and the material is re-dried under the same conditions as virgin pellets; higher regrind levels may reduce notched impact and increase the risk of silver streaks. Published data for the specific Guangzhou Keyuan New Material PC/ABS 9300MF configuration in these scenarios is limited; each converter should validate processing and end-use performance on production tooling.