HANWHA EVA 2030

Hot-melt adhesive compounding with HANWHA EVA 2030 is performed at a melt temperature of 165–185°C in a 100-litre sigma-blade mixer, followed by single-screw application through a 0.5 mm slot die. The starting formulation is adjusted to 32–38 wt% EVA 2030, 38–45 wt% C5/C9 aliphatic-aromatic tackifier, 15–22 wt% paraffin or Fischer-Tropsch wax, and 0.3–0.8 wt% hindered phenolic antioxidant, with lot-specific tackifier softening point measured by ASTM E28 and melt viscosity measured by ASTM D3236. The 20 wt% vinyl acetate incorporation, confirmed against the mill certificate under ISO 1133-1 for a melt flow rate of 30 g/10 min at 190°C/2.16 kg, reduces the ethylene crystallite melting point and broadens polar substrate wetting relative to EVA grades with lower VA content. Hot-melt viscosity at 180°C is typically maintained between 800 mPa·s and 3,000 mPa·s; values above this window are corrected by increasing wax content by 1–2 wt% rather than raising temperature, because prolonged exposure above 190°C accelerates deacetylation and acetic acid evolution. Pellets stored at relative humidity above 60% are pre-dried at 60–65°C for 4 h to keep surface moisture below 0.05 wt%. Production-scale failure is observed as gel specks on the slot die lips when the melt remains in the applicator reservoir for more than 6 h or when the heating jacket exceeds 200°C; wetted surfaces in continuous lines are therefore specified as 316L stainless steel or alloy 20. The formulation is subjected to ASTM D4498 peel testing on kraft paper and polypropylene film; peel values in the 2–6 N/25 mm range are recorded for the 20 wt% VA class, but substrate corona treatment level must be measured by ASTM D2578 and held above 38 dyn/cm or adhesion fails adhesively.

Foam Expansion Behaviour and Peroxide Cure Latency in Compression-Moulded EVA Midsoles

Compression-moulded foam compounds based on EVA 2030 are built around a 100 phr resin base, activated azodicarbonamide blowing agent, dicumyl peroxide crosslinker, zinc oxide activator, stearic acid lubricant, and calcium carbonate filler. The processing sequence uses a 5-litre internal mixer at 90–105°C for 8–12 min, followed by a two-roll mill with a nip gap of 1.5–2.0 mm to form a homogeneous preform. The critical control point is the overlap between dicumyl peroxide half-life at 170°C—approximately 1 min in technical bulletins—and the decomposition of activated azodicarbonamide at 160–180°C when ZnO is present. A ±5°C deviation from this temperature alters cell nucleation and can produce a bimodal cell size distribution or surface collapse. The preform is loaded into a 150-ton compression press with a four-cavity midsole mould heated to 165–175°C; cure pressure is 150–200 kg/cm² and the cycle is 6–10 min. Post-cure at 65°C for 24 h removes residual blowing gas and stabilizes dimensions. The finished foam is tested by ASTM D3574 for tear and flex fatigue, DIN 53512 for compression set, and ISO 868 for Shore A hardness; the target density is 0.15–0.25 g/cm³, with a surface hardness of 55–65 Asker C. Peroxide cure systems are incompatible with amine-based antioxidants and hindered amine light stabilizers at processing temperatures above 120°C; such additives consume free radicals and reduce gel fraction as measured by ASTM D2765.

The formulation gradient demonstrates the effect of filler and blowing-agent ratio on density and compression set; exact lot-specific response requires a moving-die rheometer cure curve under ISO 6502 and full-size mould trials because the cooling rate at the mould wall influences skin density and Asker C hardness by 3–5 points.

What Limits Seal Initiation Temperature When EVA 2030 Is Blended into LDPE Extrusion-Coating Skins?

Seal-initiation temperature in LDPE extrusion-coating skins is governed by the crystallite melting distribution of the sealant layer. When EVA 2030 is dry-tumbled with LDPE at 10–30 wt% and fed to a single-screw extruder with a barrier screw of L/D 24:1, melt temperature 190–220°C, and a 760 mm slot die, the VA comonomer disrupts polyethylene crystallinity and lowers the temperature at which the sealant transitions to a tacky melt. DSC measurements under ISO 11357-3 show the LDPE melting peak shifts from approximately 112°C to 98–102°C at 20 wt% EVA addition; the corresponding seal initiation temperature measured by ASTM F2029 commonly declines by 7–12°C. The seal strength measured on a 50 µm aluminium-foil-backed film by ASTM F88 at 110°C and 0.3 MPa dwell pressure is maintained above 3 N/15 mm when the EVA fraction remains below 30 wt%. Above 30 wt%, hot tack improves but the coefficient of friction increases and blocking becomes measurable after 48 h at 40°C in wound stock. Processing limits are set by deacetylation: the melt film must not remain above 240°C for more than 20 min, and the chill roll temperature is held at 15–20°C to minimize wax bloom. Published peel strength data for EVA 2030 specifically in LDPE sealant blends is limited; the above values reflect the general EVA 20 wt% class and must be confirmed with the target substrate.

Because the 30 g/10 min melt flow rate places EVA 2030 at the higher-fluidity end of the EVA range, the grade is run on injection moulding lines for flexible technical parts and closure liners when mould fill pressure is the limiting variable. A 120-ton hydraulic reciprocating-screw machine with a 40 mm screw of L/D 20:1 is set to a melt temperature of 170–195°C, a mould temperature of 20–35°C, injection pressure of 60–100 MPa, and hold pressure of 40–60 MPa. The injection speed is profiled to eliminate jetting because the melt is highly pseudoplastic; a slow first-stage filling of 10–25 mm/s followed by a fast pack transition at 95% fill reduces gate blush. Mould shrinkage is measured by ISO 294-4 and is typically 1.2–1.8% for unfilled EVA 2030, with post-mould crystallisation causing additional 0.2–0.4% change over 24 h; dimensional checks are therefore performed after conditioning at 23°C/50% RH for 48 h. Tensile properties on injection-moulded plaques per ISO 527-2 fall in the 8–15 MPa range with elongation at break of 500–700%, while Shore A hardness is 80–90 under ISO 868. The main operational boundary is melt temperature: above 200°C, acetic acid released by EVA degradation can cause mould surface pitting on unplated carbon steel; tooling is specified with chrome plating or stainless steel inserts. The grade is not suitable for melt contact with polycarbonate or polyamide engineering parts in two-component moulding because the VA comonomer reduces interphase strength and the required melt temperature difference exceeds 60°C.

When a Polyolefin Masterbatch Carrier Requires Low-Temperature Dispersion Without Sacrificing Throughput

Masterbatch producers select EVA 2030 as a carrier resin for polyolefin colour and additive concentrates when the final letdown ratio is 2–5% in low-density polyethylene or ethylene-vinyl acetate packaging films. A representative carbon black masterbatch formulation contains 40–45 wt% carbon black with iodine absorption number measured by ASTM D1510, 5–8 wt% LDPE wax, 0.3–0.5 wt% processing stabiliser, and the balance EVA 2030. Compounding is performed on a co-rotating twin-screw extruder with L/D 40:1, screw speed 300–400 rpm, barrel temperatures 150–180°C, and an underwater pelletizer producing 3 mm cylindrical pellets. The high VA content of EVA 2030 wets carbon black aggregates more effectively than neat LDPE and shortens the time to reach a filter pressure value below 0.2 MPa/g on a 14 µm screen pack according to EN 13900-5. However, the carrier’s low melting point and high MFR impose a boundary: concentrates used at letdown ratios above 8% in PP homopolymer can reduce the final modulus and heat distortion temperature; the user must validate mechanical properties under ISO 527-2 and ISO 75-2 at the target letdown. The carrier is also unsuitable for polyamide or polycarbonate masterbatch because the EVA phase degrades at the higher processing temperatures and can deposit on the breaker plate. Batch-to-batch variance in carbon black moisture below 0.5 wt% and EVA pellet surface moisture above 0.05 wt% causes screw slip in the feed zone; pre-drying at 65°C for 3 h is applied when bulk storage exceeds 60% RH.

For low-voltage cable jackets requiring halogen-free flame retardancy, EVA 2030 is evaluated in blends with linear low-density polyethylene or ethylene-propylene copolymers because the 20 wt% VA groups improve filler-particle wetting and reduce the tendency of metal hydrates to agglomerate during twin-screw compounding. A typical starting compound contains 30–40 wt% EVA 2030, 20–30 wt% LLDPE, 140–180 phr ATH/MDH with median particle size 1.5–2.5 µm, 1–3 phr vinyl silane coupling agent, 0.5–1.5 phr antioxidant, and 1–2 phr processing aid. The compound is mixed in a 75-litre internal mixer at 110–130°C to avoid peroxide pre-cure, then fed to a twin-screw extruder with barrel temperatures 120–150°C and a strand pelletizing system. The compounded pellets are extruded onto cable jackets at a melt temperature of 130–160°C; the high MFR of EVA 2030 helps maintain line speed despite filler loading. The hardened jacket must meet the vertical flame test of IEC 60332-1-2 and the halogen acid gas release limits of EN 50267-2-3. Tensile strength measured by ISO 527-2 is normally above 9 MPa, and elongation at break above 150%; the limiting oxygen index under ISO 4589-2 is maintained at 28–32%. Peroxide-curable versions of this compound are sensitive to amine-based antioxidants and sulfur-containing accelerators at temperatures above 120°C; such additives consume free radicals and reduce hot-set performance under IEC 60811-507. Published data specific to EVA 2030 in this filler class is limited; the processing window and property ranges reflect the general 20 wt% VA ethylene-vinyl acetate class and require line-specific validation.