Guangzhou Keyuan New Material PC/ABS 9300EV17 is a polycarbonate/acrylonitrile-butadiene-styrene alloy supplied in pellet form for injection moulding and extrusion. The grade designation 9300EV17 is producer-specific; it is not an ISO 1043-1:2011 material designation and does not by itself indicate filler content, impact-modifier chemistry, or flame-retardant package. Published data for this specific configuration is limited, and lot-specific certificates of analysis are required before setting production limits. Table 1 lists class-typical property ranges for unfilled medium-flow PC/ABS as a preliminary design reference, not a specification for any individual lot.

Because 9300EV17 is unfilled, the mechanical response is governed by the PC-to-ABS phase ratio, the butadiene rubber particle size distribution in the ABS phase, and the molecular mass of the polycarbonate fraction. The room-temperature Charpy values in Table 1 reflect ductile crack propagation; brittle behavior can appear below -30 °C or at sharp stress concentrators such as unradiused snap-fit roots and gate vestiges. Weld-line zones typically retain only 30% to 60% of the un-notched impact strength depending on melt-front temperature, tool surface temperature, and injection speed. Weld-line placement in hidden or low-stress areas is therefore required for load-bearing housings. Mould shrinkage in the flow direction and cross-flow direction differs by 0.1% to 0.3%, and final dimensional inspection should occur after 48 h of post-moulding stabilization because PC/ABS continues to densify after demoulding.

Moisture control is the first processing threshold. Polycarbonate carbonate linkages undergo hydrolytic chain scission when residual moisture exceeds 0.02% by weight at melt temperature. A desiccant-bed dryer with a supply-air dew point of -40 °C or lower is the minimum acceptable system; a hot-air hopper dryer cannot maintain that boundary when ambient relative humidity exceeds 60%. Drying at 80 °C to 90 °C for 4 h to 6 h from sealed containers is a starting point, but actual moisture must be verified with a Karl Fischer or equivalent analyzer. On production lines, incomplete drying appears as gate blush, silver streaks, weld-line separation, and gas bubbles in short-shot regions. This failure mode is often lot-independent and should be investigated before adjusting barrel temperatures.

At the barrel, a general-purpose three-zone screw with length-to-diameter ratio of 20:1 to 24:1 and compression ratio of 2.2:1 to 2.5:1 is sufficient for an unfilled alloy. The measured melt temperature at the nozzle should be held from 240 °C to 270 °C. The upper control limit is 280 °C; above that limit styrene-acrylonitrile yellowing and butadiene oxidation generate acrid volatiles, black specks, and reduction in impact strength. Mold temperature should be maintained between 60 °C and 80 °C with a pressurized water or oil temperature-control unit. Cavity temperatures below 50 °C produce surface flow marks, visible knit lines, and lower notched impact energy. Hot-runner manifolds are set between 235 °C and 255 °C, and valve-gate tips should not exceed 260 °C; local shear heating at gate tips can generate discoloration in colored lots even when the bulk melt remains within specification.

Rheological behavior is pseudoplastic in the injection moulding shear-rate window. Flow length/wall-thickness ratio for this class typically remains below 120:1; thin-wall sections below 1.0 mm therefore require high injection speed, elevated melt temperature, and sufficiently large gate land. Gate diameter should be 60% to 80% of the nominal wall thickness, and gate land length should be 0.5 mm to 1.0 mm to prevent jetting and surface streaks. Long flow paths can produce freeze-off before complete packing; sequential valve gating or flow leaders should be used when flow length exceeds 150 mm in wall stock below 1.5 mm.

Regrind handling introduces additional process variance. Dried virgin pellets and dried regrind should be blended gravimetrically rather than volumetrically. Regrind addition above 30% can reduce melt viscosity and notched impact strength due to polymer chain scission and rubber particle agglomeration; the exact threshold depends on regrind thermal history and particle size distribution. Reclaimed material from rejected parts with splay or bubbles should not be re-fed without re-drying because the chemical damage has already occurred. On production lines with closed-loop scrap recovery, the use of a dust-removal cyclone and metal separator is required to protect hot-runner valve gates and nozzle tips from contamination.

Which specification differences separate 9300EV17 from flame-retardant and high-heat grades?

The base 9300EV17 grade should not be considered a direct substitute for halogenated or phosphorus-based flame-retardant PC/ABS unless the supplier provides a valid UL 94 test report under IEC 60695-11-10:2013 or a recognized UL Yellow Card. Flame-retardant PC/ABS grades are often formulated to achieve V-0 at 1.5 mm or 1.0 mm; the unfilled base grade may not meet those classifications, particularly in thin-wall electronic enclosures subject to IEC 62368-1:2023. Compared with high-heat PC/ABS, the class-typical heat deflection temperature at 1.80 MPa is lower by approximately 10 °C to 20 °C; load-bearing service above 105 °C should therefore be designed with a high-heat resin. Compared with high-gloss ABS/PMMA alloys, scratch resistance and surface hardness are lower, so hardcoating or opaque coating is necessary in visible mar-prone zones. Compared with chemically resistant PC/PBT, 9300EV17 is less tolerant of aromatic solvents, fuel vapor, and concentrated alkaline detergents.

Compared with unfilled ABS, the PC-rich phase raises heat resistance and low-temperature impact strength but also raises melt viscosity and moisture sensitivity. A moulder using ABS barrel settings near 220 °C will likely encounter poor melt homogeneity, visible splay, and short-shot variability. The medium-flow behavior shown in Table 1 is suitable for wall thicknesses from 1.0 mm to 3.0 mm; gates and runners should be sized larger than those for ABS because PC/ABS exhibits a higher pressure drop per unit flow length. Compared with glass-filled PC/ABS, unfilled 9300EV17 offers lower flexural modulus and higher isotropic shrinkage. Glass-filled grades should be specified when dimensional tolerance below ±0.05 mm is required under load; unfilled material is preferred for snap-fit applications requiring higher elongation and for painting or electroplating where glass fibers can produce surface read-through.

When 9300EV17 replaces unfilled ABS in electronic enclosure and appliance housing programs

Conversion from unfilled ABS to 9300EV17 is appropriate when the application requires higher notched impact resistance, better dimensional stability under indoor heat, or improved load-bearing capability without glass fiber. Typical uses include appliance housings, electronic device frames, automotive interior trim substrates, and electrical enclosures that are not required to achieve V-0. Part design should maintain internal radii of at least 0.5 mm and nominal wall thickness from 2.0 mm to 2.5 mm to reduce sink and warpage. Rib bases should not exceed 60% of adjacent wall thickness; thicker ribs delay gate freeze and create visible sink opposite the rib. Boss outer diameter should be 2.0–2.5 times the thread diameter, and bosses should be supported by gussets to prevent cracking at screw-insertion torque.

Cavity pressure at gate freeze generally reaches 35–50 MPa for this class. A tool with 500 cm² projected area may therefore require 175–250 t clamp force; smaller machines can flash during packing. Hot-runner systems should use full-round runner cross-sections and positive valve-gate shutoffs. Cold-runner sprue bushings with rough surfaces or sharp transitions generate shear heating and black specks. Multi-cavity tools should be balance-verified with in-mold pressure sensors rather than short-shot weight alone, because PC/ABS melt compressibility and shear-sensitive viscosity can mask true filling imbalance. Automotive interior trim substrates also require low volatile organic compound and low odour behaviour. The 9300EV17 grade should be selected only with supplier data for VDA 270 odour and DIN 75201 fogging; unfilled PC/ABS may require post-moulding ventilation or emission-optimized stabilizer packages.

Chemical incompatibility with amines, aromatic solvents, ketones, and alkaline metalworking fluids is an operational boundary that must be documented in the quality plan. Under tensile stress from molded-in inserts, snap-fits, or screw bosses, PC/ABS of this class can undergo environmental stress cracking after contact with toluene, xylene, methyl ethyl ketone, or pH 10 alkaline solutions at 50 °C. Amine-based mold-release agents, certain epoxy hardeners, and strong alkaline rust-preventive oils should be excluded from all process contact. Cleaning of barrels and hot runners after PVC, acetal, or halogenated compounds requires a purging compound; residual halogen acids degrade polycarbonate during subsequent heating cycles. For ultrasonic welding, low amplitude of 30–60 µm and moderate downforce are starting points. Joint design should include shear interference of 0.2 mm to 0.4 mm. Vibration welding of this material class typically starts at amplitude 1.0 mm to 1.8 mm and pressure 2 bar to 5 bar; excessive amplitude ejects degraded melt and weakens the weld zone.

Adhesive bonding with solvent-based systems containing cyclohexanone or dimethylformamide can cause crazing; water-based polyurethane dispersions, two-part acrylics, or hot-melt polyolefins are lower-risk starting points. Surface treatment by corona or plasma at 42–50 dyn/cm wetting tension improves ink and adhesive wetting, but overtreatment embrittles the polycarbonate-rich surface layer and can reduce impact strength at bonded joints. Post-moulding machining with dull tools or high feed rates can introduce microcracks; sharp carbide tooling and compressed-air cooling should be used when deflashing or drilling is required.

Regulatory verification should not proceed without supplier documentation. EU RoHS Directive 2011/65/EU Annex II, REACH Regulation (EC) No 1907/2006 Article 33, and ISO 11469:2016 marking must be confirmed for the purchased lot. For food-contact use, compliance under 21 CFR 177.1580 for polycarbonate and 21 CFR 177.1020 for ABS must be demonstrated for the finished article; single-polymer clearances do not automatically extend to alloy migration behavior. For electrical enclosure applications, a valid UL Yellow Card and an assessment under IEC 62368-1:2023 are required before the grade can be considered a flame-retardant equivalent.

In outdoor or extended UV exposure, unfilled PC/ABS grades of this class undergo yellowing and surface embrittlement unless protected by opaque paint, film insert molding, or UV-stabilized hardcoat. Where color stability after 2000 h xenon-arc weathering under ISO 4892-2:2013 is specified, PC/ASA should be selected instead. For components exposed to automotive fuels, engine oil, or brake fluid, PC/PBT or PBT alloys are more resistant to swelling and stress-cracking; 9300EV17 is not a direct substitute in those chemical environments. In medical or laboratory equipment that undergoes steam sterilization at 121 °C or higher, repeated autoclave aging data are required because PC/ABS can lose impact strength and develop microcracks after thermal-humidity cycling. These operational boundaries are the minimum compatibility filters before a lot-specific validation program is initiated.