Kumho Petrochemical ABS HAG-7200 is an acrylonitrile-butadiene-styrene injection-molding grade positioned for high-flow cavity filling in thin-wall and large-area components. The HAG-7200 designation identifies a high-flow ABS within the manufacturer’s portfolio; the prefix separates injection grades from general-purpose and extrusion grades, while the numerical suffix reflects the specific viscosity-impact balance. Under ISO 1133-1:2022 at 220 °C with a 10 kg piston load, high-flow ABS in this class commonly exhibits melt mass-flow rates above 20 g/10 min. The exact lot-specific melt flow rate, tensile properties, and impact values must be taken from the supplier’s certificate of analysis. Published data for this specific configuration is limited in this document; engineering reference ranges provided below represent unfilled high-flow ABS resin class values and require verification before tooling or process sign-off. The material is supplied as cylindrical pellets with a typical density near 1.04 g/cm³ under ISO 1183-1:2022 and is processed by conventional reciprocating-screw injection molding. The two-phase morphology—styrene-acrylonitrile continuous phase and dispersed polybutadiene rubber domains—controls the balance between flow, rigidity, and impact strength. In product selection, HAG-7200 should be evaluated against lower-flow ABS grades when the limiting factor is filling pressure rather than impact or chemical resistance.

What distinguishes HAG-7200 from lower-flow ABS grades during cavity filling?

In injection molding, pressure loss across the runner and cavity is governed by melt viscosity under shear. HAG-7200 belongs to the high-flow ABS class in which melt mass-flow rate under ISO 1133-1:2022 is generally above 20 g/10 min, compared with 4–10 g/10 min for many extrusion and general-purpose grades. This difference reduces injection pressure demand for equivalent flow length. In spiral-flow evaluations at 230 °C and 900 bar, high-flow ABS can reach spiral lengths above 400 mm in a 2 mm flow channel, although mold geometry and cooling rate shift this value. Lower-flow ABS grades may provide higher low-temperature impact and environmental stress crack resistance because of higher molecular weight or rubber content; they are preferred for thick sections, thermoforming sheet, or extrusion profiles. HAG-7200 is not directly interchangeable with flame-retardant ABS grades, UV-stabilized grades, or high-heat ABS grades in applications requiring UL 94 V-0 at 1.6 mm, outdoor weathering, or heat deflection above 100 °C. Shear viscosity at 230 °C and 1000 s⁻¹ for high-flow ABS class may fall between 80 Pa·s and 150 Pa·s; a controlled-stress rotational rheometer in oscillatory mode can confirm tan δ and complex viscosity, but published data for this specific configuration is limited. The higher melt flow rate is generally achieved by molecular weight control rather than plasticizer addition; therefore migration of low-molecular-weight species is not an expected processing limitation, but volatile emissions should be assessed under VDA 278 or ISO 12219 for automotive interiors if required.

Pre-drying is mandatory before molding. A closed-loop desiccant dryer with supply air dew point ≤ −30 °C is preferred for moisture-sensitive ABS. Typical drying conditions for high-flow ABS are 80–85 °C for 2–4 h when ambient relative humidity exceeds 60% or when silo/open storage time exceeds 30 min. Residual moisture must be ≤ 0.08 wt% by ISO 15512:2019 before processing; moisture above this threshold can produce splay, gas splay, and surface defects at gate freeze-off. Barrel set points depend on screw size, shot weight, and residence time. A typical reciprocating-screw barrel profile from feed to nozzle may be 200 °C, 215 °C, 225 °C, 235 °C, and 240 °C. The actual melt temperature should be measured with an insertion pyrometer; for HAG-7200 class material it should remain between 220 °C and 245 °C. At melt temperatures above 250 °C, polybutadiene degradation can progress rapidly, producing yellowing, brown streaks, and notch-impact loss. Residence time at full melt temperature should not exceed 6 min. Mold surface temperature should be controlled at 40–80 °C; a temperature variation across the cavity above 5 °C can create differential shrinkage and warpage. Back pressure settings of 0.5–1.5 MPa hydraulic aid melt conditioning without excessive shear heating. Screw speed for a 35–60 mm diameter screw is typically limited to 50–100 rpm. When calculating clamp force, cavity pressure for thin-wall ABS is assumed in the 25–45 MPa range. A projected area of 0.20 m² at 35 MPa produces a cavity separating force of 7 MN, or approximately 714 metric tons; a safety factor of 1.2 may be added. Short shots in high-flow ABS are less often caused by material flow than by venting deficiencies or gate freeze-off; vents of 0.02–0.03 mm depth on the parting line should be inspected before increasing melt temperature.

Because HAG-7200 is selected for high-speed filling, the relationship between shear rate and viscosity is operationally more important than the single-point melt index. Capillary rheometry across shear rates of 100 s⁻¹ to 10,000 s⁻¹ at 230 °C can define the shear-thinning exponent for lot acceptance. High-flow ABS typically exhibits a power-law index n of 0.25–0.40 in the relevant range; a lower n indicates greater thinning and lower pressure drop at gate shear rates. The gate shear rate for a 1.0 mm side wall gate and 1.5 mm wall thickness can exceed 10,000 s⁻¹ during fast injection. Under such conditions, melt viscosity may drop below 50 Pa·s, reducing pressure loss but increasing the risk of gate blush, jetting, or splay if the melt is not homogeneous. Nozzle and hot-runner temperatures should be profiled within ±5 °C; a hot-runner imbalance of 10 °C can shift fill rates between cavities because viscosity temperature dependence of ABS is approximately −2%/°C to −3%/°C near processing temperatures. Pressure-volume-temperature behavior of ABS should be used in simulation packages with compressibility coefficients from pvT testing rather than default values. Because ABS is amorphous, it solidifies by glass transition rather than crystallization exotherm. Gate freeze-off for a 1.0 mm gate may occur in 0.8–1.8 s depending on mold temperature; holding pressure must be maintained beyond gate freeze. For thick sections above 4 mm, sink and void formation are controlled by melt cushion and holding pressure profile, not by high flow. Shot weight should be maintained at 50–80% of barrel capacity to limit residence time. Below 20% capacity, melt residence time may degrade thermal stability; above 80%, recovery time may be insufficient for complete melting. When processing colored or masterbatch-modified HAG-7200, the carrier resin may shift melt flow by ±3 g/10 min and impact by ±10%, so a weld-line impact specimen should be evaluated before production release.

Mechanical property validation and standard test designations

Mechanical data for incoming lots should be obtained after conditioning under ISO 291:2008, class 23/50 for at least 16 h. The tensile properties are typically measured on type 1A specimens according to ISO 527-2:2012 at 50 mm/min; flexural properties on 80 mm × 10 mm × 4 mm bars according to ISO 178:2019 at 2 mm/min. Notched impact resistance should be reported with specimen geometry, notch radius, and conditioning temperature. Unnotched and notched Charpy values are not interchangeable. A manufacturer’s certificate that omits these details cannot support direct material substitution. The table below lists representative property windows for unfilled high-flow ABS resin class. Values are not a substitute for the grade-specific certificate and should be used for preliminary feasibility only.

Impact values at low temperature decline; at −30 °C, established high-flow ABS materials can show a reduction in notched impact to 8–12 kJ/m², making low-temperature ductile failure possible. The selected grade should be tested under the actual part strain rate and temperature, especially for snap-fit features or structural bosses. Molded-in stress can be evaluated by solvent immersion or polariscopic inspection; for ABS, stress cracking is accelerated by aliphatic hydrocarbons, aromatic hydrocarbons, esters, and ketones. Chemical resistance should be verified under ISO 22088-2:2006 or ISO 22088-3:2006 with an applied strain matching the service condition.

HAG-7200 is appropriate for injection-molded enclosures and structural parts in which filling pressure and flow length-to-wall thickness ratio determine manufacturability. Production-scale applications reported for high-flow ABS include vacuum cleaner housings, air conditioner front panels, washing machine control housings, monitor back covers, router enclosures, and toy load-bearing components. In these applications, the grade may replace standard-flow ABS when wall sections below 1.5 mm produce short shots or weld-line failures. The material is amorphous; therefore it does not display crystalline shrinkage anisotropy, but flow-induced orientation and differential cooling still create molded-in stress. Weld-line strength in high-flow ABS can be lower than in high-impact grades when compared using ISO 179-1 notched specimens cut across the weld line; if a weld line occurs in a highly loaded feature, the design should be changed or a higher-impact grade may be required. The unstabilized ABS should not be exposed to direct outdoor weathering because polybutadiene oxidation leads to surface chalking and impact loss after relatively short UV exposure. Painted or metallized HAG-7200 parts require adhesion promotion and may release volatile compounds during post-curing; emission testing for automotive interior applications should follow VDA 278 or ISO 12219-4. For appliance housings, the resin is generally suitable where internal temperatures remain below approximately 70 °C. Sustained exposure above this threshold should be validated by UL 746B relative thermal index or ISO 2578 thermal endurance. Electrical properties, such as comparative tracking index and volume resistivity, are not primary selection criteria for natural ABS but may be relevant in electrical enclosures; material-specific CTI data should be obtained from the supplier instead of assuming PLC values.

When HAG-7200 is substituted into tooling originally designed for standard-flow ABS

Substitution of a standard-flow ABS with HAG-7200 can lower injection pressure demand by 15–30% and shorten fill time in thin sections, but it also changes the balance between packing and shrinkage. Existing tooling may require re-balancing of gates and runners because the lower viscosity can cause preferential filling of certain cavities. Gate dimensions originally designed for higher viscosity may be too restrictive; for a wall thickness of 1.2 mm, the gate depth should be 60–80% of wall thickness, or 0.7–1.0 mm, with land length 0.5–1.0 mm. Undersized gates will freeze early and require excessive holding pressure, negating the advantage of high flow. Parting line flash risk increases if the projected area is large and the clamp force is marginal; the flash gap for ABS is generally below 0.02 mm. Hot-runner systems must maintain setpoint variation within ±5 °C across all drops. Thermal variations above 10 °C between gates create near-twin viscosity differences, shifting weld-line positions and producing uneven weight. Mold shrinkages in high-flow ABS class are similar to standard-flow ABS but should be reconfirmed; the values in the property table indicate in-flow shrinkage 0.4–0.6% and cross-flow 0.5–0.7%. For flat parts with length above 250 mm, this anisotropy can drive warpage. Cooling circuits should maintain a core-cavity temperature difference of no more than 5 °C at ejection. Ejector pins and textured surfaces may require review because lower melt viscosity can permit deeper texture replication but also more frequent part sticking if the mold is polished or draft angles are below 0.5°.

Lot acceptance for HAG-7200 should include measurement of melt volume-flow rate ratio at 10 kg and 21.6 kg under ISO 1133-1:2022 as a low-cost indicator of molecular weight distribution drift. The ratio, combined with notched impact and tensile yield, can detect lot-to-lot shifts before production. Suppliers of ABS for automotive interior components are typically certified to IATF 16949:2016; processors should require material certifications under ISO 9001:2015 for non-automotive grades. Regulatory compliance should not be assumed from generic ABS data. Current declarations for RoHS Directive 2011/65/EU Annex II restricted substances and REACH Article 33 candidate list substances must be requested for the specific grade and production campaign. Food-contact applications require explicit confirmation of formulation compliance with FDA 21 CFR 175.300 or EU Regulation 10/2011; natural high-flow ABS does not automatically meet migration limits. Medical device use requires ISO 10993-1:2018 biocompatibility evaluation, which is not part of standard ABS technical data. The use of regrind is permitted at levels up to 20 wt% if the regrind is dry, uncontaminated, and from the same lot or family. Regrind levels above 20 wt% should be validated by tensile impact and notched impact testing because repeated thermal history may shift the rubber phase crosslinking and reduce toughness. Material stored in unopened, moisture-barrier packaging can retain processability for extended periods, but opened containers should be dried before reintroduction. If a lot has been dried repeatedly or exposed to high temperature, residual moisture content and yellowness index under ASTM E313-20 should be checked. Material selection for weatherable parts should consider ASA, AES, or UV-stabilized ABS rather than natural high-flow ABS.