Applications of Beijing Huamei VAX70 EVA in Industrial Manufacturing

As a manufacturer specializing in high-performance ethylene-vinyl acetate copolymer (EVA), Beijing Huamei provides VAX70 EVA for downstream partners requiring reliable material consistency across various demanding applications. The following sectors represent verified industrial use cases, with technical focus on compliance, formulation, process flow, and finished product outputs.

1. Photovoltaic Encapsulant Films

The photovoltaic industry relies on EVA for encapsulating solar cells, where clarity, crosslinking behavior, and environmental durability are essential. VAX70 is a primary polymer for film extrusion and lamination onto PV modules, directly affecting field lifetime, power retention, and cell protection. Its formulation parameters influence optical transmission, peel strength, and water vapor barrier properties, which must remain stable under outdoor exposure and temperature cycling through decades.

Industry compliance standards

• IEC 61215 (Crystalline Silicon Terrestrial Photovoltaic (PV) Modules – Design Qualification and Type Approval)
• IEC 61730 (PV Module Safety Qualification)
• UL 1703 (Flat-Plate Photovoltaic Modules and Panels)
• RoHS Directive 2011/65/EU

Typical usage ratio

• EVA content: 85–95% by weight of the encapsulant film layer, adjusted with crosslinking agents and UV absorbers based on module lamination protocols and target gel content.

Downstream process integration

• Blended with curing agents and antioxidants in twin-screw extrusion to produce pellets or directly cast films; laminated over PV cells before thermal crosslinking in module vacuum lamination ovens.

Final product types

• Mono/polycrystalline PV modules
• BIPV (Building Integrated PV) glass modules
• Flexible PV modules for lightweight or portable applications

2. Hot Melt Adhesives for Packaging

Leading packaging converters formulate EVA-based hot melt adhesives for carton sealing, label application, and case & tray assembly. Here, melt viscosity, open time, and bonding performance must align with line speed and substrate compatibility. The VAX70 grade provides critical flexibility, impact resistance, and rapid setting times required by automated packaging lines, while maintaining thermal and oxidative stability throughout storage and use.

Industry compliance standards

• FDA 21 CFR 175.105 (Adhesives – indirect food contact)
• REACH Regulation (EC) No 1907/2006
• ASTM D3236 (Standard Test Method for Apparent Viscosity of Hot Melt Adhesives)
• ISO 9001:2015 (for process and QC management)

Typical usage ratio

• EVA base polymer content: 35–55% by weight in hot melt adhesive formula, adjustable with waxes, tackifiers, and stabilizers, chosen for balancing bond strength with temperature and application substrates.

Downstream process integration

• Pelletized EVA combined with resins and additives in high-shear mixers, followed by extrusion to produce hot melt chips or blocks; end users melt and dispense adhesive on packaging lines using heated glue tanks or spray nozzles.

Final product types

• Corrugated box sealants
• Self-adhesive label layers
• Case & carton forming hot melts

3. Cable Compounds for Electrical Insulation

Wire and cable manufacturers utilize EVA for insulation and sheathing compounds, where dielectric properties, flexibility, and flame retardancy are critical. VAX70 enables precision compounding with flame retardants and plasticizers, producing insulation layers that can withstand flexing, heat, and electrical stress over prolonged service life. Stringent batch control and homogeneous dispersion of all ingredients play a key role to avoid variance in electrical resistance and breakdown performance.

Industry compliance standards

• UL 1581 / IEC 60227 (General Test for Wire & Cable Thermoplastic Insulation)
• RoHS Directive 2011/65/EU
• EN 50363-1 (Insulating Compounds – Thermoplastic and Thermosetting)
• IEC 60332-1 (Flame Retardance)

Typical usage ratio

• EVA resin: 30–65% by compound weight, balanced with flame retardants, antioxidants, and mineral fillers depending on target cable class (e.g., low smoke, low toxicity, flexibility requirements).

Downstream process integration

• Masterbatch creation via melt mixing and kneading; continuous extrusion and die-drawing over copper/aluminum wire cores, followed by cooling and reel winding under in-line quality monitors for thickness and dielectric uniformity.

Final product types

• Power cable insulation (low voltage)
• Telecommunication data cables
• Automotive & appliance wiring harnesses

4. Footwear Injection Molding Compounds

Footwear manufacturers employ EVA as the primary polymer for molded midsoles, outsoles, and sports shoe soles where shock absorption, flexibility, and resilience against repeated compression are paramount. VAX70’s controlled vinyl acetate content and melt flow rate support direct injection molding for footwear with optimized density and cushioning tailored for various footwear series. Its profile affects wear resistance, color consistency, and corporeal comfort standards in commercial-scale shoe production.

Industry compliance standards

• EN ISO 20344:2021 (Footwear Testing Methods: Mechanical/Chemical Properties)
• REACH Regulation (EC) No 1907/2006
• GB/T 15107-2013 (Chinese Standard for Shoe Sole Materials)
• Phthalate-free requirements for children’s footwear (EN 71-3)

Typical usage ratio

• EVA base: 65–95% by weight of sole compound, optionally blended with PE, crosslinking agents, foaming additives, and pigments to adjust density (150–300 kg/m³ for sneaker midsoles, 180–330 kg/m³ for casual outsoles).

Downstream process integration

• Dry blending with expansion and color additives, followed by pelletizing and direct feeding to injection or compression molding machines that form, expand, and crosslink soles under controlled temperature and pressure.

Final product types

• Athletic shoe midsoles
• Casual shoe outsoles
• Children’s footwear inserts

5. Flexible Film and Sheet Production for Industrial Packaging

Film converters use EVA-based blends for shrink film, stretch film, and non-rigid packaging applications where toughness, sealability, and puncture resistance are critical for automated packaging lines and industrial goods protection. The VAX70 grade offers superior film clarity and impact properties needed to ensure packaging integrity during transportation, storage, and handling under variable mechanical and thermal conditions.

Industry compliance standards

• FDA 21 CFR 177.1350 (Ethylene-vinyl acetate copolymer for food contact films)
• ISO 527 / ASTM D882 (Film Mechanical Testing Standards)
• EN 12311-2 (Plastic and rubber sheets for water containment – elongation requirements)
• ISO 14001:2015 (for film production environmental management)

Typical usage ratio

• EVA content: 5–35% of total blend, adjusted for target flexibility and sealing temperature, with PE or other co-polymers forming matrix structure in multilayer films.

Downstream process integration

• Melt blending and extrusion through blown or cast film lines; in multilayer coextrusion, EVA enters one or more core/sealant layers as required by final application.

Final product types

• Shrink wraps for palletizing
• Lidding films for trays
• Flexible liner sheets for industrial bags and pouches