BADAFLEX® SEBS-Comp. TPE-S 75A 1205 2K S3 is supplied as a ready-to-use SEBS-based thermoplastic elastomer compound with nominal hardness 75 Shore A under ISO 7619-1:2010. For automotive interior two-shot overmoulding onto polypropylene homopolymer or impact-copolymer substrates, the downstream addition ratio is defined as the overmoulded TPE-S mass fraction in the finished trim component. That fraction is maintained between 15 percent and 25 percent when soft-touch wall thickness is held at 1.2–2.0 mm. Below 1.2 mm, cooled edge gates with diameters of 0.8–1.5 mm exhibit premature gate freeze and flow hesitation that produce visible weld lines on grained tool surfaces. Above 2.0 mm, pack-pressure decay in tools with clamp force under 8,000 kN can create subsurface voids at the PP/TPE-S interface. The regulatory and test-method anchor set for cabin interior parts includes REACH Regulation (EC) No 1907/2006 SVHC candidate-list screening, RoHS Directive 2011/65/EU Annex II as amended by (EU) 2015/863, flammability evaluation under ISO 3795:1989 at 2.0 mm specimen thickness, fogging method reference ISO 6452:2007, and VOC/SVOC thermal desorption method VDA 278:2011. Published quantitative VOC limits for this specific grade are limited; pass/fail thresholds derive from the end-user’s OEM material specification rather than from generic compound documentation.

Melt processing is executed on two-shot injection machines with clamp force from 8,000 kN to 16,000 kN, using separate barrels for the PP substrate and the TPE-S overmould. First-shot PP melt temperature is set between 210 °C and 240 °C depending on nucleated or impact-copolymer grade. Second-shot BADAFLEX® TPE-S barrel profile is held at 190–210 °C, with nozzle temperature 205 °C and mould surface temperature 25–45 °C. Holding pressure is maintained at 30–50 MPa at the second-shot gate to prevent sink while avoiding gate freeze. Drying at 70 °C for 2 h is required when storage relative humidity exceeds 60 percent. Production-scale observations on rotary two-shot lines indicate that injection speeds above 150 mm/s across a 0.8 mm gate cause gloss banding; lowering the speed to 70–100 mm/s and raising mould temperature to 45 °C removes the defect but adds 4–6 s to the cycle. Finished terminal parts from this processing route include PP door lower insert mats, map pocket edge strips, armrest end caps, seat adjustment lever soft zones, and child-lock cover gaskets.

Does 75 Shore A Overmoulding Maintain Adhesion on PP Power Tool Housings After Damp-Heat Ageing?

Power tool grip shells are produced as two-shot assemblies in which the first shot is a filled or unfilled PP housing and the second shot is BADAFLEX® SEBS-Comp. TPE-S 75A 1205 2K S3. The overmoulded TPE-S shot mass fraction is controlled to 20–35 percent of the finished housing mass for grip wall sections between 2.0 mm and 3.5 mm. Wall sections below 2.0 mm increase cooling-rate gradients and can lower interfacial adhesion on tools where the mould is not heated; walls above 3.5 mm extend cycle time without proportional improvement in damp-heat performance. The applicable safety standard for hand-held motor-operated tools is IEC 62841-1:2014+AMD1:2021, with chemical compliance under REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU Annex II as amended by (EU) 2015/863. Damp-heat ageing may be assessed under IEC 60068-2-78:2012 at 40 °C/93 % RH, or at 85 °C/85 % RH for 168 h when demanded by the end-user specification.

Production runs use rotary two-shot machines with clamp force 1,500–4,500 kN. The PP barrel is operated at 210–240 °C; the TPE-S barrel is kept at 190–210 °C, and mould temperature is held between 30 °C and 50 °C. Injection speed for the overmould shot is set to 60–100 mm/s, with holding pressure 35–50 MPa. External mould release agents must not be used on the PP substrate or on the overmould cavity because residual release films reduce interfacial peel strength. Field data from plants without conditioned air show surface splay when the mould surface falls below the dew point, particularly below 20 °C; this defect is eliminated by raising mould temperature to 30 °C or adding dehumidified feed air to the clamp area.

Terminal finished parts include angle grinder overgrips, drill/driver rear grip shells, hammer drill vibration bands, and circular saw front handles. If delamination is detected after damp-heat cycling, the first process variables to verify are second-shot melt temperature below 190 °C, residual mould release contamination, and overmould thickness below 2.0 mm; the cause is rarely hydrolysis of the SEBS mid-block under these conditions.

Outdoor handles accumulate hydrolysis by-products at PP interfaces

At 18–30 percent overmoulded TPE-S shot mass fraction, outdoor cordless shears and hedge-trimmer handles with glass-filled PP substrates are produced with grip wall thickness 1.8–3.0 mm. The governing safety standard is IEC 62841-1:2014+AMD1:2021; environmental compliance uses REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU. Production runs on two-shot machines with 3,000–8,000 kN clamp force; first-shot PP-GF20 is injected at 220–240 °C, second-shot TPE-S at 190–210 °C, and mould surface temperature is maintained at 30–50 °C. Drying at 70 °C for 2 h is applied when packages have been opened above 60 percent relative humidity.

Tooling with cold sprue bushing diameters below 3.0 mm can cause premature gate freeze on PP-GF20 first-shot; two-shot tool designs use a valve gate or hot tip with gate diameter 1.0–1.5 mm for the overmould. In wet-storage qualification, damp-heat exposure at 40 °C/93 % RH for 168 h under IEC 60068-2-78:2012 is used to detect delamination at the PP/TPE-S interface. Adhesion loss detected after wet storage is normally traced to mould release contamination or insufficient second-shot melt temperature below 190 °C, not to hydrolysis of the SEBS mid-block. Terminal parts include rear grip shells, front handle bands, and debris guard edges. Outdoor UV exposure remains a boundary condition: unpigmented or light-colour SEBS grades may show surface chalking after 500–1,000 h xenon-arc ageing under ISO 4892-2:2013. Published data for this specific grade in light-colour, multi-year full-sun application is limited; black compounds expose less chalking but still require OEM-specific UV stabilizer packages for prolonged outdoor service.

Cable Connector Grommet Overmoulding on Glass-Filled Polypropylene

In circular connector and sensor-cable entry designs, the TPE-S functions as an injection-moulded grommet overmoulded directly onto PP-GF15 or PP-GF20 connector bodies. The overmoulded TPE-S mass fraction reaches 40–60 percent of the completed connector assembly because the grommet is thicker than the rigid body; the grommet wall thickness is maintained between 1.5 mm and 3.0 mm. The relevant electrical safety classification is UL 94 HB at 2.0 mm for a non-flame-retardant SEBS compound; if V-2 or higher is required, the material is outside its established rating envelope unless a flame-retardant variant is substituted. Chemical compliance uses REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU Annex II as amended by (EU) 2015/863. Ingress-protection targets up to IP67 are design-dependent and require compression ratio between 1.2:1 and 1.5:1, lip angles of 25–35°, and no knit line crossing the sealing bead.

Production on core-back two-shot tools requires second-shot melt temperature 190–210 °C, mould temperature 30–50 °C, and holding pressure 25–40 MPa. Vent depth at the sealing lip must not exceed 0.01–0.02 mm to prevent flash; vacuum ports at 0.02–0.05 MPa are applied to remove gas traps at sharp transitions between the rigid connector body and the soft grommet. Compression set after 72 h at 70 °C according to ISO 815-1:2019 should be checked against lot certificates; published data for this specific grade and finished-connector geometry is limited, so finished-connector testing is required. Terminal finished products include IP-rated cable entry grommets, sensor bushings, splitter sealing collars, and PP connector backshells with integrated strain relief.

Returnable logistics containers and low-force protective edge profiles use the compound as an overmoulded lip on PP or PE ribs. The TPE-S overmould shot mass fraction is held between 20 percent and 30 percent of the ribbed component, with lip thickness 1.5–2.5 mm. The overmoulded lip withstands repeated compressive cycles but is not formulated for continuous contact with mineral oil, aromatic hydrocarbons, or strong oxidising media; swelling in non-polar oils produces dimensional change and loss of sealing force. In multi-cavity tools for dunnage lid seals, hot-runner balance must maintain cavity-to-cavity melt temperature difference below 3 °C to avoid lip thickness variation above 0.1 mm. Process conditions include second-shot barrel temperature 185–205 °C, mould temperature 20–45 °C, and clamp force from 1,500 kN to 5,000 kN. The applicable chemical compliance framework is REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU. Purging between production runs is performed with PP or PE; polyacetal or PVC residues must be avoided because decomposition products can cause odour and adhesion defects in finished seals. Terminal outputs are logistics tray edge seals, protective corner bumpers, reusable dunnage lid gaskets, and edge trim on foldable large containers.

When 75 Shore A TPE-S Replaces Vulcanized EPDM in Low-Force PP Valve Seal Beads

For low-force non-potable water valves and actuator handwheel seals, the 75 Shore A compound is injected as a seal bead onto PP valve bodies or PP actuator rings. The overmoulded TPE-S bead represents 30–45 percent of the finished seal component mass, with bead thickness 1.0–2.5 mm. The substitution of vulcanized EPDM is limited to applications with compression set requirements that can be met by SEBS at service temperatures below 60 °C in wet conditions; dry-air service may extend to 80 °C for short excursions if compression force is not safety-critical. Continuous contact with chlorinated water above 2 mg/L free chlorine at temperatures exceeding 40 °C may shorten service life; published data for this specific configuration is limited. Compression set is evaluated under ISO 815-1:2019 at 70 °C/72 h, and hot-air ageing under ISO 188:2011 at 70 °C/168 h is used to detect surface hardening. Regulatory compliance follows REACH Regulation (EC) No 1907/2006 and RoHS Directive 2011/65/EU.

Process conditions specify second-shot melt temperature 190–210 °C, mould temperature 30–50 °C, and holding pressure 25–40 MPa. Production tooling uses an expanding core or two-stage slide to form the continuous seal bead without knit lines; any knit line crossing the seal lip produces a leakage path that cannot be corrected by downstream processing. Terminal products include non-potable PP valve handwheel grip sleeves, low-torque labyrinth seal beads, and actuator dust-lip rings.