EVA

EVA, or Ethylene Vinyl Acetate Copolymer, is a versatile polymer. Below is a detailed introduction to EVA:
1. Characteristics
EVA exhibits good flexibility and rubber-like elasticity, remaining flexible at temperatures as low as -50°C. It also has good transparency, surface gloss, and excellent chemical stability, aging resistance, and ozone resistance. EVA is non-toxic and offers good compatibility with fillers, coloring, and molding processes. The polarity of acetate groups increases elasticity and viscosity while reducing crystallinity and electrical properties. It is soluble in hydrocarbons and oils.
2. Factors Affecting Performance
The properties of EVA are mainly influenced by the vinyl acetate (VA) content and melt index (MI). When the melt index is fixed, a higher VA content increases EVA's elasticity, softness, compatibility, and transparency. Conversely, it becomes more rigid, with improved wear resistance and electrical insulation as the VA content decreases. For a fixed VA content, increasing the melt index lowers the softening point and improves processability and surface gloss, but reduces strength.

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