Dongguan Haohan Plastic supplies PC/ABS JH7120T as a compounded polycarbonate/acrylonitrile-butadiene-styrene alloy in pelletised form. The grade belongs to a material class in which a continuous polycarbonate phase is modified with a dispersed ABS phase to reduce melt viscosity and obtain notched impact stability that is difficult to achieve with neat polycarbonate alone. Injection-moulded electronic enclosures, appliance housings, power-tool shells, and automotive interior brackets are typical applications for this class because the balance of heat resistance, low-temperature impact, and flow length in thin-wall tools is less restrictive than that of neat polycarbonate or mineral-filled grades. Because the supplier’s lot-specific datasheet controls exact composition, the polycarbonate-to-ABS ratio is not stated in this document; published data for this specific configuration is limited. Industrial PC/ABS moulding grades of this type typically contain 50–70 wt% polycarbonate, 20–40 wt% ABS, and 2–8 wt% impact modifier or processing stabiliser packages. These intervals are not lot-specific test results but are representative of publicly available PC/ABS compounder datasheets.

The model designation JH7120T does not by itself specify filler content, flame-retardant chemistry, or impact-modifier type; it is an internal grade code that must be decoded against the supplier’s datasheet. Substitution with another PC/ABS grade solely on the basis of similar melt flow rate is not recommended, because impact-modifier particle size and polycarbonate molecular weight distribution control low-temperature ductility. Before processing, pellet moisture is reduced on a desiccant-bed dryer with dew point ≤ −30 °C. Typical drying conditions of 80–90 °C for 3–4 h lower residual moisture below 0.02 wt% as measured by ISO 15512:2019; failure to maintain this condition produces splay, silver streaking, and hydrolytic degradation of the polycarbonate domains. The product is normally supplied in 25 kg multi-wall paper bags or bulk octabins; batch-to-batch melt flow variation should be monitored on arrival using ISO 1133-1:2022 at 260 °C and 5 kg.

What processing boundaries define JH7120T on injection moulding lines?

On hydraulic injection moulding machines of 250–350 t clamp force, the typical barrel profile for unfilled PC/ABS is rear 240–250 °C, centre 260–270 °C, front 270–280 °C, and nozzle 270–280 °C. The manufacturer’s datasheet may narrow this window; the moulder should treat it as an initial parameter set rather than a specification for JH7120T. Screw back pressure is held at 5–10 bar hydraulic to avoid high-shear heating, and screw rotation speed is limited to 50–100 rpm on a 20–25 mm general-purpose compression screw with L/D 20:1–24:1 to prevent excessive shear-induced degradation. Melt residence time should not exceed 8 min at melt temperature; longer residence shifts the ABS phase toward yellowing and reduces Charpy notched impact. A nozzle setpoint deviation of ±5 °C can be sufficient to change surface gloss in thin-wall parts, so hot-runner feedback should be calibrated before production startup.

Mould temperature is maintained at 70–90 °C using pressurised water or oil thermolators. Below 60 °C, injection moulding trials on thin-wall enclosures show delamination at knit lines, jetting, and reduced surface gloss; above 100 °C, cycle time extends without proportionally improving impact strength. Published data for this specific configuration is limited, so these boundaries should be verified with short-shot fill studies and in-mould pressure transducers. Hopper dryers with −20 °C dew point or lower are used when moulding ambient humidity exceeds 60% RH; otherwise sealed hoppers are required. A melt cushion of 3–6 mm and screw decompression of 3–5 mm are usually sufficient to prevent drool without pulling air into the melt. Field observations on twin-screw compounding lines with L/D 40:1 indicate that PC/ABS at high throughput and excessive screw fill can form polycarbonate-rich gels; screen packs of 100–250 µm are therefore placed before the die to trap char particles and disperse the ABS phase. For hot-runner systems, manifold and nozzle setpoints should be held within 270–285 °C to avoid freeze-off at the gate and thermal degradation in stagnant zones.

Mechanical property mapping according to ISO 527-2 and ASTM D638

For PC/ABS alloys of this class, tensile properties are controlled by polycarbonate molecular weight, ABS rubber particle size, and interfacial adhesion. Because the supplier’s product-specific datasheet was not independently available, the following table reports representative PC/ABS injection-moulding grade ranges collected from publicly available compounder datasheets and should not be read as guaranteed values for JH7120T. All values are for dry-as-moulded specimens at 23 °C unless stated.

The differentiation of JH7120T from other products within the supplier’s PC/ABS range is therefore assessed by lot-specific tensile, impact, and melt-flow certificates rather than by class-typical values. A shift in melt volume-flow rate from 10 cm³/10 min to 18 cm³/10 min at 260 °C/5 kg reduces fill pressure but may lower Charpy notched impact by 20–40% depending on ABS rubber content. This inverse relationship is typical for PC/ABS alloys because the lower-viscosity grade usually contains a higher ABS fraction or lower polycarbonate molecular weight. For moulding trials, the ISO 527-2 Type 1A tensile specimen and the ISO 179-1 Type A notched specimen should be taken from the same cavity and conditioning atmosphere to avoid artefactual differences from orientation or moisture.

Thermal and rheological differentiation from filled PC/ABS grades

Mineral-filled PC/ABS grades differ from unfilled PC/ABS of this class in melt rheology and failure mode. Published data for this specific configuration is limited; therefore selection of JH7120T versus filled grades should be based on the supplier’s measured flexural modulus and not on class-typical intervals. Filled grades exhibit lower transverse ductility because mineral particles act as stress concentrators; the shift from ductile tearing to brittle fracture in Charpy testing can occur at filler levels as low as 5 wt% in thin-wall sections. Glass-filled PC/ABS with 10 wt% glass fibre may raise flexural modulus to 3500–5000 MPa but can reduce Charpy notched impact at −30 °C to below 8 kJ/m², whereas unfilled PC/ABS typically retains values above 10 kJ/m².

Capillary rheometry at 260 °C shows unfilled PC/ABS melts are shear-thinning with a power-law index of 0.25–0.45 in the shear-rate range 100–5000 s⁻¹. Filled grades show higher entrance pressure loss and require larger sprue and runner diameters to prevent early freeze-off. In practice, a 6 mm tunnel gate may be sufficient for unfilled PC/ABS of this class at a wall thickness of 2.5 mm, whereas a 8 mm gate is often specified for mineral-filled variants. On a 300 t injection moulding machine producing thin-wall covers, unfilled PC/ABS typically requires lower holding pressure than glass-filled PC/ABS, which exhibits quicker gate freeze and narrower processing latitude. Filler anisotropy also influences shrinkage: platy talc tends to reduce warpage relative to glass fibre, but weld-line strength is usually lower.

In comparison with neat ABS, the PC/ABS class represented by JH7120T exhibits higher heat deflection temperature and improved notched impact at −20 °C, but it requires higher drying and melt temperatures. In comparison with neat polycarbonate, the ABS modification reduces melt viscosity and improves chemical stress-cracking resistance to some solvents, while lowering tensile modulus and optical transparency. Against high-flow PC/ABS grades for thin-wall electronics, a standard unfilled grade may show lower melt volume-flow rate but higher heat deflection temperature; the specification decision should therefore be driven by the flow length-to-wall-thickness ratio and the required heat resistance under load.

When UL 94 V-0 compliance drives specification of halogen-free PC/ABS

When an electrical enclosure or power-supply housing carries a requirement for flame retardance, the moulder cannot infer that JH7120T is equivalent to a halogen-free FR PC/ABS. The UL 94 rating is specific to a thickness and colour range listed on the supplier’s UL Yellow Card. Before tooling release, the processor should obtain the Yellow Card file number and verify the exact rating at the intended nominal wall thickness, typically 1.5 mm or 2.0 mm. If JH7120T is not listed in the supplier’s UL file, a third-party UL 94 test according to IEC 60695-11-10:2013 or ASTM D3801-20a is required, but the result cannot be used for UL certification without a listed grade.

Halogen-free FR PC/ABS grades often contain aryl phosphate flame retardants, which plasticise the melt and reduce heat deflection temperature by 10–20 °C relative to unfilled non-FR PC/ABS. They also exhibit stress-cracking sensitivity when exposed to alkaline cleaners and can show lower comparative tracking index values, typically below 250 V on the IEC 60112:2020 test. Published data for this specific configuration is limited; if JH7120T is a non-FR grade, it is not interchangeable with FR grades in designs where the plastic is a live part barrier or where glow-wire requirements of IEC 60695-2-11:2021 apply. For outdoor or UV-exposed housings, UV stabilisation and colour-lot documentation should be requested separately, because PC/ABS can yellow under continuous UV exposure. Phosphate-based flame retardants may also exhibit surface migration under high humidity; this failure mode is generally less relevant for unfilled non-FR PC/ABS, but should be evaluated when a grade is later recompounded with flame-retardant masterbatch.

A compliance review for procurement of PC/ABS JH7120T should verify the following standard certifications against the supplier’s current documentation. Table 2 lists the minimum verification set for EU and North American electrical and electronics applications.

Lot-level incoming inspection should record melt volume-flow rate, moisture content, and the supplier’s batch number for traceability. The operational boundary for this material is established by pre-drying and melt residence control; mechanical, thermal, and flame-retardant claims require the supplier’s approved datasheet and regulatory certificates. Published data for this specific configuration is limited, so tooling decisions should be made only after lot-specific certification is available.