In direct-injection footwear lines, Globalprene® SBS 3741 is processed as the base elastomer for expanded microcellular soles. The polymer is pre-blended with paraffinic process oil at 8 to 15 phr, precipitated silica at 5 to 10 phr, azodicarbonamide blowing agent at 1.2 to 2.0 phr, zinc oxide at 0.8 to 1.2 phr, and stearic acid at 0.5 to 1.0 phr. Compounding is conducted in a co-rotating twin-screw extruder with L/D ratio 36 to 44, using barrel temperatures from 120 °C to 150 °C and a screw speed of 250 to 400 rpm. Pelletized compound is dried to 0.02 % moisture before direct injection on rotary multi-station machines with clamp force between 35 tonnes and 80 tonnes. Injection cylinder temperatures are maintained at 150 °C to 170 °C, mold temperature is held at 30 °C to 50 °C, and injection pressure is controlled between 50 MPa and 70 MPa. Apparent density is specified between 0.25 g/cm³ and 0.45 g/cm³ according to ISO 845. Shore A hardness is monitored under ISO 868. Finished articles include running shoe midsoles, casual sandal soles, and expansion-molded comfort footwear. Compliance screening applies REACH Annex XVII entry 50 limits for the eight listed polycyclic aromatic hydrocarbons in rubber components with direct skin contact. Reclaim of granulated sole scrap containing residual azodicarbonamide is restricted to 5 wt% or less because higher addition levels shift cell size distribution and cause density scatter. Lot-to-lot variance in oil absorption should be checked against the supplier certificate of analysis before scale-up because porosity defects arise at the injection gate when compound viscosity drops more than 10 % from baseline.

At Which Usage Ratio Does 3741 Alter Hot-Melt PSA Shear Resistance After 7-Day Thermal Aging?

In hot-melt pressure-sensitive adhesive compounding, Globalprene® SBS 3741 is charged as the styrenic block elastomer at 100 phr with a tackifying resin system at 100 to 130 phr and naphthenic process oil at 20 to 40 phr. Hydrogenated rosin ester or C5/C9 aliphatic-aromatic resin is selected based on the storage temperature of the finished label or tape. A hindered phenolic antioxidant is added at 0.3 to 0.5 phr and a phosphite co-stabilizer at 0.2 phr to suppress gel formation in the unsaturated polybutadiene midblock. Mixing is executed in a jacketed sigma-blade kneader at 160 °C to 175 °C for 45 to 90 min under nitrogen blanket. Apparent viscosity after mixing is measured at 165 °C with a Brookfield Thermosel under ASTM D3236-14. Slot-die coating is performed at 150 °C to 165 °C with coat weights between 15 g/m² and 25 g/m². Loop tack is measured under FINAT FTM 9; 180° peel adhesion is measured under PSTC-101 Test Method A. Static shear adhesion after 7 days at 70 °C is screened under ASTM D3654-12; shear adhesion failure temperature is evaluated by ASTM D4498-07(2015). Adhesive systems for food packaging side seams are screened under FDA 21 CFR 175.105 and repeated-use rubber articles under FDA 21 CFR 177.2600. Melt hold time must not exceed 3 h at 175 °C to avoid chain scission and darkening. Finished goods include carton sealing tapes, label stock, and film-backed mounting tapes. Outdoor exposure without UV-blocking face stock reduces peel retention due to oxidation of the diene midblock.

When a Polymer-Modified Bitumen Formulation Must Demonstrate 72-Hour Storage Stability Under EN 14023

The binder recipe is based on a penetration-grade bitumen such as 70/100 or 50/70 with Globalprene® SBS 3741 added at 3.0 to 5.5 wt% of the final binder mass. An optional sulfur crosslinking agent at 0.05 to 0.15 wt% is metered after the polymer swelling stage to stabilize the SBS network without producing excessive gelation. High-shear dispersion is conducted in a rotor-stator mill at 3,500 rpm to 5,000 rpm and 180 °C to 190 °C for 60 to 120 min. The mill is stopped when the torque plateau after polymer addition is stable for 15 min. The finished PMB is stored in nitrogen-blanketed horizontal tanks with low-agitation paddles at 160 °C to 170 °C. Release tests include softening point by ASTM D36-14, penetration by ASTM D5-19, elastic recovery by ASTM D6084-18, and storage stability by EN 14023:2010 using the 72-h tube test procedure. A storage-stable PMB for dense-graded road surfacing normally maintains a softening point difference below 2.5 °C after 72 h. Terminal products include heavy-duty pavement binders, airport runway mastics, and high-stress intersection wearing courses. The styrenic domains of 3741 provide network strength, while the diene midblock absorbs maltenes and imparts elastic recovery. Filler addition before complete dispersion is held below 5 wt% of total binder unless performance-grade verification is carried out under AASHTO M320-21. Published data for this specific configuration is limited, so mixer torque logs and softening point pull samples are used as primary scale-up records.

Solvent-borne contact adhesives for furniture lamination and automotive headliner layup use Globalprene® SBS 3741 as a partial replacement for chloroprene rubber. A high-solids sprayable system contains 100 phr of total elastomer, of which 20 to 40 phr is 3741 and the balance is modified chloroprene. Tackifying resin is charged at 40 to 60 phr, magnesium oxide at 4 phr, zinc oxide at 2 phr, and hindered phenolic antioxidant at 1 phr. The solvent blend comprises acetone, cyclohexane, and methyl ethyl ketone at a total solids content of 12 to 18 wt%. Mixing proceeds in a closed vacuum dissolver at 1,000 rpm until the final viscosity is 300 to 600 mPa·s at 25 °C. The adhesive is applied by HVLP spray or roller coater at 150 g/m² to 200 g/m² wet film. Drying time before lamination is 30 to 60 min at 25 °C. Peel strength is determined by ASTM D903-98(2017) or ISO 11339:2018. Solvent management obligations for coating and adhesive installations are assessed under Directive 2010/75/EU. Hydrophobic fumed silica is added at 0.5 to 1.5 phr to reduce sag on overhead surfaces. Finished products include laminated kitchen worktops, automotive door panel composites, and acoustic foam-backed headliners. Because the butadiene midblock is unsaturated, these contact adhesives are not specified for prolonged UV exposure without a protective coating or opaque coverstock.

Torch-Applied Bitumen Coating Lines Where Mixer Torque Indicates Dispersion Completion

In modified bituminous membrane production, Globalprene® SBS 3741 is incorporated into oxidized or distillation-grade bitumen at 8 to 12 wt% of the coating compound. Limestone powder filler is added at 25 to 35 wt%, and a styrenic-compatible sulfur donor is used at 0.1 to 0.2 wt% where high-temperature flow resistance is required. A horizontal plough mixer or vertical high-shear bitumen plant is heated to 170 °C to 190 °C. Dispersion is complete when the mixer torque stabilizes after the polymer swelling phase, usually 90 to 150 min from the final polymer addition. The coating compound is applied on a polyester or glass-fibre carrier through calender rolls controlling thickness between 3 mm and 6 mm. Cold flexibility is tested under EN 1109:2014; heat resistance and flow resistance are assessed under EN 1110:2010. Final sheets are sold as torch-applied waterproofing membranes for concrete bridge decks, basements, and roofs. Conformity is declared under EN 13707:2013 for flexible sheets for waterproofing; North American projects may reference ASTM D6164-19 for SBS-modified bitumen sheet materials. The addition level is lowered to 6 wt% only when the substrate is fully embedded and no torch reheating is specified in the project specification. Lower polymer content reduces low-temperature flexibility below -10 °C as measured by EN 1109:2014.

For injection-molded soft-touch automotive and appliance parts, Globalprene® SBS 3741 is let down with polypropylene homopolymer in a co-continuous thermoplastic elastomer compound. A practical starting ratio is 100 phr 3741, 30 to 50 phr polypropylene homopolymer with melt flow rate 20 to 40 g/10 min at 230 °C/2.16 kg, 20 to 40 phr paraffinic oil, and 0.1 to 0.3 phr processing stabilizer. Compounding is performed in a co-rotating twin-screw extruder with L/D ratio 32 to 40, using starve feeding and downstream oil injection after the first 8 barrel segments. Barrel temperatures ramp from 150 °C at the feed throat to 190 °C at the die. Pelletized TPE is dried at 60 °C for 2 h when storage relative humidity exceeds 60 %. Injection molding uses clamp force from 500 kN to 1,800 kN, injection pressure between 60 MPa and 90 MPa, and mold temperatures of 20 °C to 45 °C. Hardness is controlled between Shore A 45 and 65 under ISO 868. Tensile properties are measured according to ISO 37:2017. Melt flow rate is measured by ISO 1133-1:2022. Electrical and electronic compliance is documented under IEC 62321-5:2013 for lead and cadmium and IEC 62321-8:2017 for phthalates. Finished articles include appliance feet, cable grommets, gear lever bellows, and floor mat edge strips. Prolonged outdoor exposure is limited because the unsaturated butadiene segment is susceptible to oxidation unless UV-stabilized masterbatches are added at 1.0 to 2.0 wt%.