| HS Code | 959699 |
| Bio Carbon Content | ≥80% |
| Vinyl Acetate Content | 18.0% |
| Melt Flow Rate 190 C 2 16 Kg | 2.0 g/10min |
| Density | 0.939 g/cm³ |
| Melting Point Dsc | 87 °C |
| Vicat Softening Temperature | 65 °C |
| Tensile Strength At Break | 11 MPa |
| Elongation At Break | 750% |
| Hardness Shore A | 93 |
| Brittleness Temperature | -70 °C |
| Flexural Modulus | 40 MPa |
| Crosslinkability | Peroxide-crosslinkable |
As an accredited Braskem America SVT2180 EVA Copolymer Resin,Bio-Circular Attributed (≥80% Bio-Carbon),Crosslinkable Foam Grade factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaged in 25 kg polyethylene bags, this bio-circular EVA copolymer resin arrives as free-flowing pellets for crosslinkable foam production. |
| Container Loading (20′ FCL) | One 20′ FCL loaded with Braskem America SVT2180 EVA Copolymer Resin, Bio-Circular Attributed (≥80% Bio-Carbon), Crosslinkable Foam Grade. |
| Shipping | Shipping: Supplied as solid EVA resin pellets in moisture-resistant packaging. Store in a dry, clean area away from ignition sources. Transport as non-hazardous material in standard freight containers or bags. Avoid excessive heat and humidity to preserve crosslinkable foam properties. Ensure proper labeling for bio-circular content when applicable. |
| Storage | Store Braskem America SVT2180 EVA Copolymer Resin in a cool, dry, well-ventilated area away from direct sunlight, heat sources, sparks, and oxidizing agents. Keep containers tightly sealed and undamaged to prevent moisture uptake and contamination. Avoid excessive heat and humidity, which can cause clumping or degradation. Follow first-in, first-out stock rotation. |
| Shelf Life | Shelf life typically two years from shipment when stored in original, unopened packaging under recommended dry, cool conditions. |
Crosslinked ethylene-vinyl acetate foam for footwear midsoles is compounded from Braskem America SVT2180 in a 75 L intermeshing internal mixer with drop temperature 105–115°C. The batch transfers to a two-roll mill maintained at 90–100°C, where dicumyl peroxide is added at 0.5–1.2 phr, azodicarbonamide at 2.0–6.0 phr, zinc oxide at 1.0–3.0 phr, and stearic acid at 0.5–1.0 phr. Because SVT2180 is bio-circular attributed at ≥80% bio-carbon under mass-balance allocation, the physical carbon-14 signal measured by ASTM D6866-24 Method B is allocation-dependent and is not a pellet-level tracer; chain-of-custody documentation under ISCC PLUS is required for bio-based claims under EN 16785-1:2015. Resin stored at relative humidity above 60% is pre-dried at 70°C for 2 h to prevent steam-induced cell collapse. The compounded preform is loaded into a 500 t compression press with oil-heated platens at 160–175°C; cavity pressure is 8–12 MPa and cure time is 8–12 min for a 10 mm midsole. The central processing conflict arises from the competing temperature-dependent rates of peroxide crosslinking and azodicarbonamide gas release. If platen temperature exceeds 178°C during the first 3 min, the melt crosslinks before full expansion, producing density gradients greater than 0.05 g/cm³ across the part when measured by ISO 845. If platen temperature remains below 158°C, azodicarbonamide decomposition is incomplete, and post-mold expansion of 2–4% occurs within 24 h, altering dimensional stability assessed by ISO 1923. Gel fraction is measured by boiling-xylene extraction for 72 h and should reach 65–85% before free foaming is terminated; lower gel fraction produces tear strength below 2.5 kN/m under ISO 34-1 method B. Hardness is measured with an Asker C durometer according to JIS K 7312; production lots are typically held to 45–55 Asker C for midsole cores. The bio-circular attributed feedstock may shift Mooney viscosity by ±5 MU relative to fossil-EVA controls when measured by ISO 289-1; SVT2180-specific lot-to-lot data is limited and should be captured on the production MES.
Representative screening matrix for general crosslinkable EVA foam appears below; SVT2180-specific validation is required because bio-circular lot viscosity and residual catalyst content can shift the balance.
| Formulation variable | DCP (phr) | ADC (phr) | Density (ISO 845) (g/cm³) | Asker C (JIS K 7312) | Tear strength (ISO 34-1 B) (kN/m) |
|---|---|---|---|---|---|
| Low crosslink, fine cell | 0.6 | 3.0 | 0.20 | 48 | 2.8 |
| Balanced midsole | 0.9 | 4.5 | 0.16 | 44 | 2.4 |
| High expansion, low density | 1.2 | 6.0 | 0.12 | 38 | 1.9 |
Amine-based antioxidants should be excluded from the midsole formulation because they consume peroxide radicals and suppress gel fraction; published data for the SVT2180/amine interaction is limited, but the peroxide consumption mechanism is documented in peroxide manufacturer technical literature.
Azodicarbonamide decomposes exothermically at 200–220°C and releases approximately 220 ml/g of gas, while dicumyl peroxide has a half-life of 1 min at 171°C and 0.1 min at 193°C. The kinetic gap between these curves defines the processing window. If ADC decomposition outpaces peroxide crosslinking, gas bubbles nucleate in a low-viscosity melt, producing coarse cells with mean diameter above 400 µm and tear strength reductions of 15–25% relative to a fine-cell control when measured by ISO 34-1 method B. The mechanism is cell wall rupture before a continuous gel network forms; gel fraction must reach 65–85% by boiling-xylene extraction for 72 h before the foam plate is fully opened. On a 44:1 L/D twin-screw extruder operated at 90–110°C barrel profile and 200–250 rpm, ADC and DCP are pre-dispersed without decomposition, but a +3°C deviation in zone 5 may produce localized scorch. Scorch is detected as brown specks and reduces Asker C hardness by 3–5 points; rheological monitoring with a Mooney viscometer at 100°C per ISO 289-1 identifies pre-crosslinked batches. If free foaming is performed on a 300 t press, the pressure release rate is typically controlled at 0.5–1.0 MPa/s; faster release causes cell wall tears in low-gel melt.
Continuous sheet foam operations using SVT2180 shift from conduction-limited expansion to surface quench-dominated expansion when calendered sheet thickness drops below 0.8 mm. The surface layer reaches 120–130°C within 20 s while the core remains at 150–160°C, producing a dense skin. Density measured by ISO 845 increases from 0.18 g/cm³ to 0.24 g/cm³ in the outer 0.2 mm, and the skin-to-core density ratio becomes a critical quality parameter. A 3-roll inverted L calender with 250 mm diameter rolls and 0.005 mm runout is specified; roll temperature is maintained at 70–85°C and roll gap at 0.6–0.75 mm for final gauge. Machine-direction tear strength may exceed cross-direction tear strength by 20–30% because of cell elongation; this anisotropy is measured by ISO 34-1 method B and must inform die-cutting orientation for gaskets and adhesive tapes. Thickness tolerance at this gauge is held to ±0.05 mm using in-line laser calipers, and any roll with peak-to-valley variation above 0.05 mm is diverted to edge trim. Published data for SVT2180-specific gauge tolerance below 0.8 mm is limited; the above values are derived from general crosslinkable EVA sheet behavior and should be validated on the target line.
Closed-cell recovery mats and athletic matting are crosslinked to a gel fraction of 70–80% to limit indentation after repeated loading. The controlling property is compression set measured by ISO 1856 method A after 22 h at 70°C; values above 8–10% indicate under-cure, processing aid migration, or excessive blowing agent residue. Production-scale compression presses with 300 t clamp and 1,200 × 1,800 mm platens are loaded with preforms at 10–12 kg/m² to achieve final density 0.10–0.14 g/cm³. Rebound resilience measured by ASTM D3574 test H typically falls between 40% and 55% for this density class. At the lower end of the density range, tear strength falls below 2.5 kN/m under ISO 34-1 method B, so fabric lamination or edge bonding is applied to prevent crack propagation during die-cutting. The bio-circular attributed resin requires ISCC PLUS mass-balance certification and bio-carbon testing by ASTM D6866-24 Method B when the finished mat carries a bio-based claim in the EU under EN 16785-1:2015; the chain-of-custody documentation must be retained for each batch because the physical bio-carbon content may differ from the attributed allocation.
Closed-cell gaskets made from SVT2180 require closed-cell content of at least 90% when tested by ASTM D1056 or ISO 4638; deficiencies below this threshold allow water absorption above 5% by volume and potential seal failure. Compression set is measured by ISO 815-1 method A at 70°C for 72 h; values below 15% at 25% deflection are typical acceptance limits for industrial gaskets. The material is compression molded at 160–170°C platen temperature and 10–12 MPa cavity pressure for 10–14 min, depending on sheet thickness. Thickness recovery after 50% compression for 24 h at 23°C is measured by ASTM D3574 test D; recovery below 90% indicates plastic flow from under-crosslinking or excessive processing aid. Die-cutting of 2–6 mm sheet stock at temperatures below 20°C can cause edge tearing because the foam is notch-sensitive; heated dies at 40–50°C reduce edge defects. The bio-circular attributed feedstock may introduce trace polar species that shift moisture absorption by 0.5–1.0% compared with fossil-EVA controls; gasket specifications should therefore include a water absorption limit per ASTM D1056 rather than assuming equivalence.
Automotive interior NVH parts made from SVT2180 crosslinked foam are validated for heat aging by ISO 188 at 90°C for 168 h; tensile strength retention below 70% and elongation retention below 60% indicate oxidative chain scission. The vinyl acetate segment releases acetic acid under elevated temperature, so fogging must be measured by ISO 6452 or SAE J1756 gravimetric method and held below 2 mg for interior applications. Processing on a 1,000 t compression press with multi-cavity molds requires deliberate degassing before crosslinking; if compressed gas is not vented, blistering appears during post-cure aging at 85–95°C. Cell size distribution is measured microscopically by ASTM D3576; a mean cell size below 200 µm and cell density above 10⁵ cells/cm³ support acoustical absorption in the 1,000–4,000 Hz band, but part-level validation must be performed by impedance tube testing per ISO 10534-2. Thermal conductivity of closed-cell EVA foam at 0.05–0.08 W/m·K is often measured by ASTM C518; however, published SVT2180-specific thermal conductivity data is limited, so automotive thermal insulation targets require measured panels rather than extrapolated values.
| Property | Test standard | Condition | Typical automotive acceptance |
|---|---|---|---|
| Heat aging tensile retention | ISO 188 | 90°C, 168 h | ≥70% |
| Fogging | ISO 6452 | 100°C, 16 h | ≤2 mg |
| Compression set | ISO 1856 | 70°C, 22 h | ≤10% |
| Mean cell size | ASTM D3576 | microscopy | ≤200 µm |
| Acoustic absorption | ISO 10534-2 | 1,000–4,000 Hz | part-specific |
SVT2180-specific acceptance values require OEM validation against full part geometry and mounting conditions.
Adhesive carrier foams are slit from 1.0–1.5 mm crosslinked sheet stock and corona-treated to 42–48 mN/m surface energy before coating with solvent-based acrylic adhesives. Surface energy is measured with dyne pens per ASTM D2578, and thickness tolerance is held to ±0.1 mm because a 600 mm slot-die coater requires uniform caliper for consistent coat weight. Peel adhesion on stainless steel is tested by ASTM D3330 method A after 20 min dwell; values below 3 N/cm indicate insufficient corona treatment or processing aid bloom on the foam surface. The bio-circular attributed resin may alter surface polarity relative to fossil EVA, so corona dosage is verified on every slit roll rather than assumed from fossil-grade settings.
Competitive Braskem America SVT2180 EVA Copolymer Resin,Bio-Circular Attributed (≥80% Bio-Carbon),Crosslinkable Foam Grade prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615380400285 or mail to sales2@liwei-chem.com.
We will respond to you as soon as possible.
Tel: +8615380400285
Email: sales2@liwei-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Braskem America SVT2180 is an ethylene-vinyl acetate copolymer resin classified as a crosslinkable foam grade, supplied with a bio-circular attributed biogenic carbon allocation of at least 80%. The material is intended for chemically crosslinked closed-cell foam processing rather than unmodified film extrusion or rigid injection molding. In practice, the resin is compounded with organic peroxide cure agents, chemical blowing agents, zinc oxide activators, and processing aids before expansion in compression molding, injection foaming, or autoclave foaming lines. The bio-circular attribution is a mass-balance chain-of-custody designation, not a claim of biodegradability or compostability. Direct analytical verification of biogenic carbon may be carried out using ASTM D6866-21 or ISO 16620-2:2019; those methods answer a different question than a mass-balance certificate such as ISCC PLUS. The grade is used in footwear midsoles, insoles, sports mats, cushion packaging, thermal insulation, gaskets, and impact-protection components. The exact melt flow rate, vinyl acetate content, and density for SVT2180 must be obtained from the producer’s certificate of analysis or technical data sheet; published data for this specific configuration are limited in this document.
For crosslinkable EVA foam grades of this class, class-level process-control values typically include a melt mass-flow rate in the range 1.5–4.0 g/10 min at 190°C/2.16 kg under ASTM D1238-20, a vinyl acetate content of 15–28 wt%, and a base-resin density of 0.935–0.950 g/cm³ under ASTM D1505-10. These ranges are not a substitute for the SVT2180 product specification. Vinyl acetate content controls crystalline melting point depression, low-temperature flexibility, and compatibility with peroxide cure systems. Higher vinyl acetate content generally improves softness and filler acceptance but lowers upper service temperature and can increase compression set if the cure network is underdeveloped. Melt mass-flow rate controls mixing torque and melt strength during gas expansion; values above the foam-grade band may cause cell rupture, while excessively low values can reduce blowing-agent dispersion and increase mold-fill pressure.
The principal difference is feedstock attribution rather than a necessary change in polymer backbone chemistry. Conventional EVA foam resins are manufactured from fossil naphtha, whereas SVT2180 carries bio-circular attribution through a mass-balance framework that assigns renewable biogenic carbon to the resin output. If the producer maintains equivalent vinyl acetate content and melt flow rate, the peroxide cure response and blowing-agent expansion behavior are expected to be comparable to a fossil reference grade. The physical and rheological behavior remains governed by the same structural variables: vinyl acetate weight fraction, melt mass-flow rate, molecular weight distribution, and long-chain branching.
Compared with high-VA hot-melt EVA grades, which often exhibit melt flow rates above 25 g/10 min, crosslinkable foam grades are normally controlled below 6 g/10 min to retain melt strength during gas expansion. Compared with low-density polyethylene foam resins, the vinyl acetate units in SVT2180 reduce crystallinity and increase chain flexibility, which supports the formation of softer closed-cell foam with higher elongation. Compared with bio-based polyurethane foams, EVA foam is thermoplastic before crosslinking and uses a different cure chemistry based on organic peroxide decomposition rather than isocyanate-polyol addition. The bio-circular version should not be confused with physically bio-based EVA that may show a direct 14C measurement corresponding to the claimed percentage. In mass-balance attribution, the renewable carbon allocation may be concentrated in a portion of the output stream while the final polymer remains structurally equivalent to fossil EVA.
On injection foaming lines, a reciprocating screw with a compression ratio of 2.5:1–3.0:1 and L/D ratio of 20:1–24:1 is commonly used for EVA foam compounds. The feed and compression zones are held below 120°C to prevent premature blowing-agent decomposition, while the nozzle temperature may be allowed to reach 160–180°C only at the point of injection. Clamp force must be sufficient to resist mold breathing during gas expansion; insufficient clamp tonnage produces flash, density gradients, and dimensional variation. Observed production-line failure modes include gas blowholes at knit lines, silver streaks from moisture or volatiles, and plate-out on mold surfaces from blowing-agent residues. The use of SVT2180 does not eliminate these failure modes because the bio-circular feedstock does not alter the underlying peroxide-cure physics. Qualification of SVT2180 as a replacement for a fossil EVA foam grade requires comparison of the certificate of analysis, rheometer cure curve, and blown foam density against the reference material under the same machine settings. Published data for this specific substitution on a named injection foam platform are limited.
In production-scale crosslinking of EVA foam, the thermal decomposition of the organic peroxide and the gas-yielding reaction of the blowing agent must be synchronized with the compound’s melt viscosity profile. Dicumyl peroxide, a common cure agent, has a half-life of approximately 10 h at 117°C, 1 h at 135°C, and 1 min at 171°C. Azodicarbonamide, the dominant chemical blowing agent for EVA sheet and molded foam, decomposes exothermically in the range of 195–215°C when activated with zinc oxide or zinc stearate, releasing roughly 220 mL/g of gas at standard temperature and pressure. These two reactions are not independent. If the viscous melt crosslinks too early, the expanding gas cannot nucleate and grow into uniform closed cells, producing cracked foam or dense skin layers. If the blowing agent decomposes before sufficient network formation, cell walls rupture and the foam collapses.
Actual processing therefore uses staged temperatures. An internal mixer with tangential rotors and a fill factor of 0.70–0.80 is typically dropped at 105–115°C to avoid blowing-agent decomposition during mixing. A two-roll mill is then operated at 70–80°C with a friction ratio of 1.15–1.25. The compounded sheet is expanded in a hydraulic compression press at 150–180°C. Mold pressure is not arbitrary because it must keep gas in solution until the cure network has sufficient melt strength to support expanding cells. Surface scorching, plate-out, and delamination occur when the cure temperature overshoots the blowing-agent induction period or when mold-release chemistry interacts with acetic acid released from EVA degradation. The order of addition on the mill or internal mixer also controls scorch: fillers, zinc oxide, and stearic acid are dispersed before dicumyl peroxide; adding peroxide above 105°C can generate scorch particles that later appear as hard specks in the foam. Published SVT2180-specific cure kinetics are limited; the producer should be consulted for recommended peroxide and blowing-agent concentrations.
Low-density EVA foam below 0.15 g/cm³ is produced by increasing chemical blowing-agent loading and reducing filler content, but the response is not linear. Azodicarbonamide is typically used at 2.0–6.0 phr in crosslinked EVA foam; dicumyl peroxide is held between 0.7 phr and 1.2 phr, and zinc oxide at 1.0–3.0 phr functions as a blowing-agent activator. Increasing azodicarbonamide above the upper limit without increasing crosslink density leads to cell coalescence, coarse cell-size distribution, and reduced tear strength. Calcium carbonate filler raises foam density and reduces rebound but improves dimensional stability and tear resistance. Moving below 0.15 g/cm³ therefore forces a trade-off between density and mechanical robustness. Crosslink density is controlled through gel content or rheometer torque; compression set after 22 h at 70°C under 50% deflection per ASTM D395-18 is a practical production control. If compression set exceeds the target, the network is often undercured. The remedy is not always additional peroxide; it may require a co-agent such as triallyl cyanurate or trimethylolpropane trimethacrylate to increase crosslink efficiency without increasing scorch. A higher vinyl acetate EVA grade shifts the rubber plateau to lower temperature and improves low-temperature flexibility, but it can also reduce heat resistance and increase compression set at the same cure level. The exact vinyl acetate content of SVT2180 must be confirmed from the producer’s certificate of analysis because it controls both the glass transition region and compatibility with the peroxide cure system.
Regulatory treatment of SVT2180 requires separating the bio-circular feedstock documentation from the finished article requirements. The bio-carbon attribution is supported by chain-of-custody certification under ISCC PLUS or a comparable mass-balance framework; analytical verification of biogenic carbon may be performed by ASTM D6866-21 or ISO 16620-2:2019. The base polymer falls within the olefin polymer family and, when unmodified and meeting extraction limits, may be assessed against FDA 21 CFR 177.1520. However, foam formulations containing peroxide decomposition residues, blowing-agent by-products, or colorants must be evaluated on the finished article. European users should assess the grade under REACH 1907/2006 and, for food contact, under EU 10/2011 with migration testing appropriate to the foam density and surface area.
| Assessment | Standard / Method | Purpose |
|---|---|---|
| Biogenic carbon allocation | ISCC PLUS mass-balance certificate | Bio-circular attribution |
| Biogenic carbon analysis | ASTM D6866-21 or ISO 16620-2:2019 | Direct 14C measurement |
| Melt mass-flow rate | ASTM D1238-20 at 190°C/2.16 kg | Grade rheology and batch consistency |
| Density | ASTM D1505-10 or ISO 1183-1:2019 | Base resin density and foam density control |
| Vinyl acetate content | ASTM D5594 or producer FTIR method | Comonomer level and flexibility control |
| Flexible cellular tensile properties | ASTM D3574-17 | Foam tensile and tear performance |
| Compression set | ASTM D395-18 | Foam recovery after compression |
| Hardness | SRIS 0101 Asker C | Foam firmness classification |
| Food-contact base polymer | FDA 21 CFR 177.1520 | Olefin food-contact status |
Storage prior to blending is governed by moisture uptake and contamination rather than extensive drying. EVA is less hygroscopic than polyamide or polyurethane, but when ambient relative humidity exceeds 60%, surface moisture or pellet condensation can create steam during expansion and cause cell-size irregularities. A conditioned drying step at 60°C for 2–4 h is applied only when incoming moisture above 0.1% by Karl Fischer titration is confirmed. The resin must not be processed above 230°C for extended periods because EVA begins to liberate acetic acid through deacetylation. This release causes corrosion on steel tooling, crosslink interference, odor in the finished foam, and surface deposits on molds. Amine-based additives are generally incompatible with peroxide-cured EVA foam because they scavenge free radicals, producing retarded cure rates and nonuniform crosslink density. Continuous service of EVA foam is generally limited to temperatures below 80°C; published data for SVT2180 in long-term high-temperature load-bearing applications are limited, so accelerated heat-aging evaluation per ASTM D3045 or a comparable practice is required before acceptance.
