Applications of Formosa Plastics TAISOX 7870S EVA in Industrial Manufacturing

Produced using high-purity ethylene vinyl acetate copolymerization, TAISOX 7870S EVA is engineered for rigorous processing requirements and delivers consistent performance across several highly regulated industries. Below are the principal industrial manufacturing sectors where this grade achieves proven downstream value, each marked by distinct compliance needs, specific formulating standards, and targeted production goals.

1. Photovoltaic Encapsulant Sheets for Solar Modules

Solar module manufacturers rely on TAISOX 7870S in the production of EVA-based encapsulant films, which serve as the critical adhesive and protective interlayer that binds photovoltaic cells to glass and backsheet components. This application requires stringent gel content and clarity, as well as UV and heat resistance, to secure module longevity and maintain power output over decades of field operation.

Industry compliance standards

• IEC 61215:2021 (Crystalline silicon terrestrial photovoltaic modules – Design qualification and type approval)
• UL 1703/UL 61730 (Flat-Plate Photovoltaic Modules and Panels Safety Standards)
• RoHS (Restriction of Hazardous Substances Directive, EU 2011/65/EU)
• ISO 9001:2015 Quality Management Systems

Typical usage ratio

• 70–100 wt% as the main polymer matrix for encapsulant compositions; vinyl acetate content and crosslinking levels tailored according to required encapsulation properties, typically adjusted via curing agents at 1–3 phr.

Downstream process integration

• Melt compounding and extrusion to produce EVA masterbatch pellets; followed by calendering or sheet extrusion to obtain films; lamination with photovoltaic cells under vacuum and heat to cure the encapsulant in position.

Final product types

• Photovoltaic encapsulant films (sheet and roll)
• Finished crystalline silicon and thin-film solar panels
• Building-integrated photovoltaic glass modules

2. Hot Melt Adhesives for Packaging and Bookbinding

Converting operations in the adhesives sector use TAISOX 7870S as the backbone polymer for hot melt adhesives designed for flexible packaging, carton sealing, and bookbinding applications, where controlled viscoelasticity and strong adhesion at a range of temperatures are critical to maintain high-speed production and secure bonding on diverse substrates.

Industry compliance standards

• FDA 21 CFR 175.105 (Adhesives for food packaging)
• EN 923:2015 (Adhesives – Terms and definitions)
• ISO 14001:2015 (Environmental Management Systems for adhesive manufacturing)
• REACH Regulation (EC) No 1907/2006 compliance regarding raw material safety

Typical usage ratio

• 25–50 wt% of total adhesive blend; adjusted based on required open time, tack, and substrate compatibility; plasticizers and tackifiers typically formulated at 10–30 wt% each to fine-tune performance.

Downstream process integration

• Hot blending in sigma blade or Z-blade mixers at controlled temperatures; direct charging into extrusion or drum filling units for pellet or block adhesive forms; subsequent application by melt coating, slot die extrusion, or spray systems on assembly lines.

Final product types

• Hot melt adhesive pellets and blocks
• Pressure-sensitive tapes
• Case and carton sealants
• Book spine bindery adhesives

3. Wire and Cable Insulation Compounds

Wire and cable compounders incorporate TAISOX 7870S into insulation and sheathing composites for power, telecom, and automotive cable applications, exploiting its flexibility, dielectric properties, and compatibility with flame-retardant and UV-stabilizing systems to meet both electrical and mechanical durability requirements.

Industry compliance standards

• UL 1581 (Reference Standard for Electrical Wires, Cables, and Flexible Cords)
• IEC 60502-1 (Power cables with extruded insulation)
• RoHS Directive (EU 2011/65/EU)
• CSA C22.2 No. 38 (Thermoset-Insulated Wires and Cables)

Typical usage ratio

• 40–80 wt% in cable compound formulations; modified depending on flexibility, tensile strength, and flame resistance demands; flame retardants (such as ATH) and processing aids added at 20–30 wt% in high-performance mixes.

Downstream process integration

• Dry blending and melt-kneading with compounding extruders; pelletizing for storage and logistics; final extrusion over copper, aluminum, or fiber optic conductors to form insulated cable cores, followed by jacketing and curing where required.

Final product types

• Low-voltage and medium-voltage cable insulation
• Telecommunication cable sheaths
• Flexible wires for automotive harnesses

4. Footwear Midsoles and Outsoles in Sports and Leisure Shoes

Footwear manufacturers utilize TAISOX 7870S to engineer EVA foam formulations that deliver lightweight cushioning and rebound in midsoles and outsoles for athletic, casual, and children’s shoes. This application benefits from tightly controlled cell structure and uniform expansion for reliable fit, shape, and long-term comfort even after repeated flexing and compression cycles.

Industry compliance standards

• ISO 20345:2022 (Personal protective equipment – Safety footwear)
• EN ISO 20871:2018 (Footwear – Test methods for outsoles)
• GB/T 15107-2013 (Chinese National Standard for footwear performance)
• REACH Regulation (Annex XVII restrictions on phthalates and heavy metals)

Typical usage ratio

• 50–65 wt% as the principal foam polymer; blown with azodicarbonamide or other safe blowing agents at 2–6 phr; crosslinkers and plasticizers incorporated based on required durometer and compression set.

Downstream process integration

• Melt blending with additives and blowing agents; injection or compression molding using high-temperature steel molds; expansion and setting in defined cavity volumes; trimming and surface finishing before assembly into shoe units.

Final product types

• EVA midsoles and outsoles for sports shoes
• Casual walking shoe soles
• Children’s shoe pads and sandals

5. Foam Sheets and Blocks for Packaging and Automotive Interiors

Converters of protective and cushioning packaging materials, as well as automotive OEMs, select this material for foam sheets and blocks where dimensional stability, shock absorption, and processability are required. The fine cell morphology and resilience enables repetitive impact protection in electronics, appliance packaging, and interior automotive parts.

Industry compliance standards

• ISO 12048:1994 (Packaging – Complete, filled transport packages – Compression and stacking tests)
• OEM automotive standards (e.g., GM GMW15473, Ford WSS-M99P32-A1 for interior trim)
• REACH Regulation compliance for restricted substances
• RoHS compliance for electronics packaging end-uses

Typical usage ratio

• 60–85 wt% of foam blend; blowing agent and nucleating agent quantities set to achieve target density (typically 25–80 kg/m³); additives for fire retardance and static dissipation included as required per OEM specs.

Downstream process integration

• Melt blending and extrusion foaming with controlled cooling to achieve precise thickness and cell size; slitting and die-cutting to finished sheet or custom block shapes; surface lamination or printing for automotive interior fitments.

Final product types

• Protective foam sheets for packaging
• Foam blocks for electronics and appliance transport
• Automotive interior cushioning inserts

6. Sealant and Caulking Compounds for Building and Construction

Building materials producers employ 7870S EVA to formulate flexible, solvent-free sealants and caulking compounds used for expansion joints, window glazing, and prefabricated panel assembly. The copolymer's elongation and adhesion profiles allow for reliable sealing under repeated thermal cycling or structural movement.

Industry compliance standards

• ASTM C920 (Standard Specification for Elastomeric Joint Sealants)
• EN 15651-1:2017 (Sealants for non-structural use in joints in buildings and pedestrian walkways)
• ISO 11600:2002 (Building construction – Sealants – Classification and requirements)
• REACH and RoHS compliance for building interior product safety

Typical usage ratio

• 15–30 wt% within solventless sealant bases; with fillers, plasticizers, and adhesion promoters making up balance; adjusted for required flexibility, flow, and curing profile.

Downstream process integration

• Melt blending in planetary mixers; addition of pre-dispersed pigments and rheology modifiers; degassing and filling into sausage or cartridge packaging for site application; applied and tooled at joint sites, sets via ambient curing.

Final product types

• Elastic caulks for concrete and masonry joints
• Window and door glazing sealants
• Facade panel joint compounds