Bhansali Engineering Polymers (BEPL) supplies ABS ABS 7000 as an unfilled acrylonitrile-butadiene-styrene injection molding grade within the Absolac portfolio. The grade is positioned for applications requiring room-temperature and low-temperature notched impact retention, moderate stiffness, and predictable melt flow for thin-to-medium wall tooling. The polymer matrix consists of a grafted polybutadiene rubber phase dispersed in a styrene-acrylonitrile copolymer continuous phase; the butadiene content is adjusted to shift the failure mode from brittle crack propagation to shear yielding under multiaxial stress. Incoming material identification typically uses density, ash content, and melt mass-flow rate. The nominal density is 1.04 g/cm³ per ISO 1183-1; ash content is generally below 0.05 %; melt mass-flow rate is measured at 220 °C under 10 kg load per ISO 1133-1:2022 and is typically reported in the 15–25 g/10 min range. These values are lot-dependent and should be verified against the certificate of analysis.

Material Identity and Specification Boundary

The specification boundary for ABS 7000 is defined by mechanical, thermal, and electrical performance. Tensile yield stress per ISO 527-2 is usually 40–48 MPa, tensile modulus 2100–2400 MPa, and nominal strain at break 15–30 %. Flexural strength per ISO 178 is typically 60–70 MPa, with flexural modulus 2000–2300 MPa. Charpy notched impact per ISO 179-1/1eA at 23 °C is typically above 30 kJ/m², while Izod notched impact per ISO 180/A is frequently reported in the 30–45 kJ/m² range. At -30 °C, notched impact values can fall below 10 kJ/m², which must be considered for unheated exterior components. Vicat softening temperature per ISO 306/B50 is typically 94–98 °C; heat deflection temperature under 1.82 MPa is approximately 88–92 °C per ISO 75-2. The grade is not a heat-resistant ABS and should not be used for continuous service above 80 °C under load.

Electrical property values are consistent with unfilled ABS: volume resistivity approximately 10¹⁵ Ω·cm, surface resistivity 10¹⁴ Ω, and dielectric strength 25–35 kV/mm per IEC 60243-1. Unless otherwise identified as specification limits, these values are representative lot values and are not guaranteed; the certificate of analysis for a specific production lot controls.

What Distinguishes ABS 7000 from High-Flow and Heat-Resistant ABS Grades?

Compared with high-flow ABS grades whose melt mass-flow rates exceed 40 g/10 min, ABS 7000 trades spiral flow length for higher notched impact strength and improved resistance to weld-line cracking. High-flow ABS can fill wall sections down to 1.2 mm, but notched Izod values often fall below 15 kJ/m². ABS 7000 is better suited to nominal wall thicknesses of 2.0–3.5 mm where impact retention is more critical than maximum flow length. Compared with general-purpose ABS, ABS 7000 has a higher rubber phase content, a tensile modulus approximately 10–15 % lower, and significantly higher notched impact. Compared with heat-resistant ABS grades, ABS 7000 exhibits lower Vicat softening temperature by approximately 8–15 K and lower heat deflection temperature, but it processes at lower melt temperature with reduced thermal degradation risk.

Pre-drying is mandatory when ambient relative humidity exceeds 60 % or when silo storage time exceeds 48 h in uncontrolled conditions. Desiccant dryer setpoint is 80 °C for 3–4 h, with dew point below -40 °C and drying air flow not less than 0.15 m³/h per 1 kg/h throughput. Moisture content above 0.1 % leads to splay, silver streaks, and loss of notched impact due to hydrolysis at the butadiene graft interface. Processing on a reciprocating screw injection molding machine should use a general-purpose polyolefin or ABS screw with L/D of 20:1 to 25:1 and compression ratio of 2.0:1 to 2.5:1. Melt temperature measured at the nozzle is typically 220–250 °C; a barrel profile from feed to nozzle is commonly 180 °C, 210 °C, 230 °C, and 240 °C. Back pressure of 0.5–1.0 MPa and screw surface speed of 0.2–0.5 m/s are sufficient; higher shear rates increase melt temperature and yellowing. Mold temperature should be maintained at 40–70 °C. Below 40 °C, weld lines and molded-in stress increase; above 70 °C, cycle time lengthens and dimensional control becomes more difficult. Clamp force requirements are normally 4–6 kN/cm² of projected area. Residence time at 240 °C or above should not exceed 5 min; on hot-runner systems, externally heated manifolds should avoid dead spots because stagnation causes brown streaking and carbonized gels. Purging with HDPE or general-purpose polystyrene is recommended after processing thermally sensitive resins. Regrind addition up to 20 % by weight in virgin material is typically acceptable when regrind is re-dried and free of fines. At 30 % regrind, notched impact and melt flow drift should be monitored per lot; above 30 %, impact-critical parts may show unacceptable batch-to-batch variance.

When Thin-Wall Electrical Enclosures Require High Impact at Low Temperature

For thin-wall electrical enclosures with nominal wall thickness between 2.0 and 3.5 mm, ABS 7000 is employed when the part must survive drop impact at -10 °C to -20 °C without brittle fracture. The higher butadiene content raises energy absorption during crack initiation, but flow length is lower than high-flow ABS. Gate sizing should be 0.6–0.8 times the nominal wall thickness, with fan or tab gates preferred over pinpoint gates to reduce shear-induced free rubber degradation. Weld line efficiency for the grade is typically 50–70 % of the unnotched base resin strength depending on mold temperature and melt temperature; for load-bearing bosses or snap fits located at weld lines, mechanical testing of molded plaques is required. UL 94 classification for the natural grade is typically HB at 1.5 mm; ABS 7000 is not a V-0 material. Automotive interior trim, appliance housings, vacuum cleaner bodies, and office equipment covers use ABS 7000 where high impact and matte-to-medium gloss surfaces are acceptable. It is not recommended for external unpainted parts because ABS undergoes UV-induced oxidation, chalking, and embrittlement; carbon black or UV stabilizer packages are needed for outdoor exposure. Published weathering data for this specific unfilled grade is limited.

Regulatory documentation accompanying commercial shipments normally includes RoHS compliance to Directive 2011/65/EU as amended, REACH SVHC screening under Regulation EC No 1907/2006, and absence of cadmium, lead, mercury, hexavalent chromium, PBB, and PBDE at the homogeneous material level. The grade is not food-contact certified unless specifically declared for a given lot; no FDA 21 CFR 177.1020 designation should be assumed. The chemical resistance profile is typical of ABS. It withstands aqueous acids, dilute alkalis, and aliphatic hydrocarbons but is attacked by ketones, esters, aromatic hydrocarbons, and chlorinated solvents. Environmental stress cracking can occur in contact with certain plasticizers, cutting oils, and mold-release agents; compatibility testing per ISO 22088-3 is advisable for stressed parts.