SABIC 731S-701S: More Than Toughness, a Choice of Precision

Under SABIC’s LEXAN™ brand, 731S-701S features a deep black, high-gloss surface while retaining the outstanding mechanical properties of polycarbonate (PC). This high-flow injection molding grade is an ideal material in high-end manufacturing sectors such as electronics and automotive, especially for parts with strict requirements for light blocking and surface aesthetics. Below is a comprehensive look at the unique value of this black PC.

I. Decoding the Grade: What Does LEXAN™ 731S-701S Mean?

• LEXAN™: SABIC’s trademark for its polycarbonate products, backed by over half a century of technological expertise.

• 731S: Indicates a standard viscosity, high-flow injection molding series. “7” generally refers to a general-purpose grade, “3” denotes medium-high flow, “1” is a modification identifier, and “S” highlights optimized mold release performance, suitable for fast filling of complex molds.

• 701S: This code represents black (opaque). The “S” suffix may indicate food contact compliance (specific COA required) or UV stabilization. This material is pure black with no light transmission, and its surface can achieve high-gloss, matte, or textured finishes, meeting light-blocking and premium appearance demands.

II. Key Properties: Performance of the Black Version

This black LEXAN™ 731S-701S retains the superior mechanical and thermal properties of the PC base while delivering a pure black, opaque appearance:

• Optical properties: Opaque; no light transmittance value. The surface can achieve high-gloss black, matte, or textured effects, fulfilling light-blocking and aesthetic requirements.

• Impact strength: Notched impact strength of 80–90 kJ/m² at 23°C, 3–5 times that of ordinary ABS, capable of withstanding severe conditions such as drops and impacts.

• Heat resistance: Heat deflection temperature (under 1.82 MPa) of 130–135°C; long-term service temperature around 120°C.

• Flowability: Melt flow index (300°C/1.2kg) of 18–22 g/10min, more than 50% higher than standard PC, ideal for thin-wall parts (e.g., below 0.5mm) and long flow path structures.

• Dimensional stability: 24h water absorption of only 0.15%, minimal deformation in humid and hot environments, ensuring precision fit.

• Other characteristics: V-2 flame retardancy (some batches may achieve V-0), good electrical insulation, resistance to oils and weak acids/alkalis.

III. Processing Advantages: Why Injection Molders Prefer This Black Material

1. High flow, low stress: Easily fills thin-wall areas with low molded-in stress, reducing the risk of cracking.

2. Easy release, reduced drag marks: Optimized mold release allows damage-free ejection of deep-cavity or threaded parts without additional mold release agents.

3. Broad drying tolerance: More forgiving of drying time deviations than conventional PC, though strict drying to moisture <0.02% is still required.

4. Effortless high-gloss black finish: The material’s inherently high blackness, combined with a glossy mold, directly yields a mirror-like black surface without painting.

IV. Typical Applications: High-End Scenarios for Black PC

• Electronics & electrical: Light-blocking charger housings, smart meter enclosures, LED display bezels, black connector insulators.

• Automotive: Instrument cluster light-blocking covers, center console trim parts, ambient light housings (to prevent light leakage).

• Medical & healthcare: Light-avoidance components such as dialyzer end caps, surgical instrument handles (if FDA certified).

• Safety & protection: Black face shield frames, side covers for protective goggles, and other non-transparent structural parts.

V. Our Services

We provide a stable supply of genuine SABIC 731S-701S black material with certificates of origin, COA, and MSDS. We also offer full technical support including material selection, mold flow analysis, trial molding, and modification.