Bada AG BADAFLEX® SEBS-Comp. TPE-S 60A 1047 is a thermoplastic elastomer compound based on hydrogenated styrenic block copolymer, supplied as free-flowing pellets for injection molding and extrusion. The TPE-S designation places the material within the styrenic block copolymer elastomer class under ISO 18064:2022; the SEBS segment identifies saturated ethylene/butylene mid-blocks between hard polystyrene end-blocks. The 60A suffix denotes a nominal indentation hardness of 60 Shore A determined in accordance with ISO 48-4:2021, with commercial tolerance generally observed at ±5 Shore A. The suffix 1047 is a grade-specific formulation or internal color designation controlled by Bada AG. Because the polystyrene domains function as reversible physical crosslinks, the compound remains thermoplastic through repeated melt cycles and does not require a vulcanization step. The saturated mid-block differentiates it from non-hydrogenated SBS, reducing susceptibility to ultraviolet, ozone, and thermo-oxidative degradation while extending the maximum practical service temperature.

Published product-specific data for BADAFLEX® TPE-S 60A 1047 is limited; the technical positioning must therefore be read against the broader unfilled SEBS compound class at 60 Shore A. The compound is characterized by low density, high elastic recovery, and relatively low processing temperatures compared with engineering thermoplastics. It is typically considered where soft-touch haptics, low-temperature flexibility, and non-halogenated formulation are required, but where continuous hydrocarbon oil contact or high-temperature creep resistance is not the primary design load. The material is not hygroscopic in the manner of polyamides, but surface condensation can occur after cold storage and must be removed before melt processing.

Is the Mid-Block Hydrogenation in SEBS-Comp. A Decisive Control Variable?

The hydrogenated ethylene/butylene mid-block governs the low-temperature behavior and the resistance to chain scission during processing. In unhydrogenated SBS, the polybutadiene mid-block contains unsaturation that is reactive toward oxygen and ozone; hydrogenation converts this to a saturated aliphatic mid-block. This structural change raises the onset of meaningful thermo-oxidative degradation to approximately 230 °C to 250 °C, depending on stabilizer package, and permits continuous upper service temperatures commonly cited in the range of 70 °C to 90 °C for unfilled SEBS compounds. The polystyrene end-block glass transition temperature remains near 95 °C to 100 °C, while the ethylene/butylene mid-block glass transition is below -40 °C. This phase separation produces a serviceable rubber plateau between the two transitions without requiring covalent crosslinking.

The 60 Shore A hardness is achieved through a balance of styrene block content, paraffinic or naphthenic process oil loading, and, in some formulations, low-density filler. Styrene block content in this hardness class commonly falls between 20 wt% and 30 wt%, while the soft phase is plasticized with a non-aromatic oil to reduce hardness and increase elongation. The exact additive package for 1047 is not publicly disclosed; consequently, swelling, extractables, and migration behavior must be confirmed with Bada AG. Hydrogenation also reduces the reactivity of the mid-block with mineral oils and fatty acids, although prolonged exposure to aromatic solvents, chlorinated solvents, or high-aniline-point oils will still plasticize or swell the material. The melt viscosity is shear-thinning, and the compound should not be exposed to melt temperatures above 250 °C for extended residence times because styrene domain disruption and oil volatilization produce viscosity shifts and surface defects.

When the grade is evaluated against standard laboratory methods, the following ranges are typical for unfilled SEBS-based TPE-S compounds in the 60 Shore A hardness class; they are not batch-certificate values for 1047.

The property envelope is strongly influenced by oil content. Higher paraffinic oil addition depresses tensile strength and tear strength while improving flow length and softness; lower oil content raises hardness and modulus but reduces elongation. For thin-wall injection molded components, tensile strength values above 8.0 MPa are generally associated with lower melt flow and may require higher injection pressures. The compression set values at 70 °C reflect the reversible physical crosslinks; under sustained compressive stress at elevated temperature, the styrene domains begin to creep, producing higher set than crosslinked TPV or thermoset rubber. This is the principal performance boundary for sealing applications.

When Demolding Temperature and Screw Recovery Time Constrain Thin-Wall Production

In injection molding, the compound is typically processed with a melt temperature between 180 °C and 220 °C, measured at the nozzle. A mold temperature of 20 °C to 50 °C is sufficient for most geometries, but thin-wall sections below 0.8 mm frequently exhibit short shots, flow lines, or jetting when the melt front falls below 185 °C. Demolding temperature is a practical bottleneck because the soft SEBS compound retains elastic deformation until cooled below approximately 45 °C; ejection too early produces gate-stringing and dimensional distortion. Cooling time is therefore extended for thick sections, and mold-temperature control across the cavity should be maintained within ±5 °C to avoid differential shrinkage.

Screw geometry for injection molding of SEBS-based TPE-S is generally specified with an L/D between 18:1 and 22:1 and a compression ratio between 2.5:1 and 3.0:1. Excessive shear from high compression ratios or high screw speed can produce frictional heat beyond 250 °C, resulting in oil volatilization, splay, and brown streaking. Back pressure in the range of 0.5 MPa to 1.5 MPa is commonly applied to homogenize the melt; higher back pressure increases plastication work but may be necessary when adding masterbatch or regrind. Sizing the shot to 60–80 % of barrel capacity is recommended for consistent residence time and viscosity control.

Before melt processing, pellets exposed to ambient humidity above 50 %RH or cold-to-warm plant transitions should be dried for 2 h to 4 h at 60 °C to 80 °C in a desiccant dryer with a dew point below -20 °C. Residual moisture above approximately 0.05 % by weight produces surface splay and can reduce tensile elongation in the molded part. The compound is not hydrolytically unstable, but trapped moisture is converted to steam at melt temperature, creating internal voids. In extrusion, a single-screw extruder with a compression ratio of 2.5:1 to 3.0:1 and a screen pack as fine as 60 mesh is generally adequate; a vacuum vent is advised when running high regrind ratios. Published processing data for this specific configuration is limited; the above parameters are representative of industrial practice for SEBS-based compounds in this hardness class.

A Comparative Boundary Against TPU, TPV, and Non-Hydrogenated SBS

The primary difference between SEBS-Comp. 60A and non-hydrogenated SBS is the saturated mid-block. SBS compounds are often lower in cost and can achieve similar hardness, but their unsaturated butadiene segments are vulnerable to yellowing, embrittlement, and surface cracking after prolonged UV exposure. SEBS compounds resist ozone attack and maintain tensile retention better under outdoor weathering; however, they generally display higher melt viscosity at equivalent hardness and require stricter temperature control to avoid oil migration.

Compared with thermoplastic polyurethane at 80 Shore A to 90 Shore A, the SEBS compound has a lower specific gravity of 0.88–0.92 g/cm³ versus roughly 1.10–1.20 g/cm³ for polyester or polyether TPU. This provides a weight advantage of approximately 20–25 % per unit volume. The SEBS compound also offers better hydrolysis resistance than polyester TPU and remains flexible at lower temperatures. However, TPU exhibits substantially higher tensile strength, tear strength, and abrasion resistance, and TPU is superior for oil, fuel, and polar-solvent contact. The appropriate replacement boundary is usually defined by abrasion and chemical exposure; if the application requires Taber abrasion resistance above 100 mg loss per 1000 cycles under ASTM D4060-19, TPU is generally favored.

Against thermoplastic vulcanizate at similar 60 Shore A hardness, the SEBS compound has lower compression set at room temperature but higher compression set at 70 °C and 100 °C. TPV compounds contain a dynamically vulcanized EPDM phase, which provides a true chemically crosslinked rubber network; this yields superior long-term sealing force retention. SEBS-Comp. 60A 1047, being fully thermoplastic, can be reprocessed more easily and often produces lower odor, lower extractables, and better colorability when the additive package is controlled. The choice between TPV and SEBS therefore turns on the thermal and mechanical severity of the seal, with TPV preferred for continuous hot-air or hot-oil sealing above 100 °C and SEBS preferred for consumer and packaging applications where reprocessing and organoleptic neutrality dominate.

In applications where low-temperature flexibility, soft-touch haptics, and non-halogenated formulation are primary requirements, the material is positioned for grip inserts, consumer goods, flexible connectors, packaging liners, and certain non-invasive medical device components. Its upper continuous service temperature is generally below 90 °C, and sustained load-bearing parts should not be exposed to aromatic solvents, chlorinated cleaning agents, or hot mineral oils. If used in food-contact or medical applications, the finished article must be evaluated against the relevant end-use regulation; candidate raw materials may be assessed under FDA 21 CFR 177.1810 for styrene block polymers, EU Regulation (EU) No 10/2011, RoHS Directive 2011/65/EU, and REACH Regulation (EC) No 1907/2006. Biocompatibility is not implied by the base polymer; testing under ISO 10993-5 or USP Class VI must be conducted on the specific compounded grade and sterilized article. Product-specific regulatory certificates for 1047 are batch- and formulation-dependent and should be confirmed with Bada AG before applications are locked.