by What is Ethylene Vinyl Acetate?
Ethylene vinyl acetate (EVA) is a versatile thermoplastic polymer that is produced from the copolymerization of ethylene and vinyl acetate monomers. EVA has properties that are intermediate between polyethylene and polyvinyl acetate and its physical properties depend on the proportions of the monomers used. The physical and chemical properties of EVA can be tailored based on the application through modifying the vinyl acetate content.
Characteristics of EVA
The proportion of vinyl acetate ranges from 10–40% by weight, with the most common grades containing 15–30% vinyl acetate. Lower vinyl acetate content produces a material with higher flexibility and softness while higher vinyl acetate content results in a softer and more elastic material. EVA has excellent clarity, flexibility, impact strength, adhesion properties and good resistance to UV light, acids, and alkalis. It has low melting points between 60–120°C depending on vinyl acetate content. EVA exhibits very good weathering, ozone and chemical resistance with good aging properties.
Applications in Adhesives and Sealants
Ethylene vinyl acetate is commonly used in hot melt adhesives and pressure sensitive adhesives due to its clarity, flexibility, and adhesion properties. Hot melt adhesives based on EVA bind dissimilar substrates quickly and form strong, durable bonds once cooled. They are commonly used to bond foams, films, nonwovens, wood, and other porous substrates. EVA pressure sensitive adhesives provide tack, adhesion and cohesion at ambient temperatures. EVA sealants exhibit excellent adhesion, flexibility and bonding to various substrates like glass, wood, metals etc. making them suitable for construction and automotive applications.
Uses in Films and Packaging
EVA films are extensively used in food packaging due to their clarity, gloss, flexibility, high impact strength and sealing properties. They provide an excellent barrier to moisture and grease while permitting oxygen and carbon dioxide permeability. EVA films containing 16–18% vinyl acetate are used in applications like cling films, heavy-duty bags, shrink films, liners etc. Higher VA content films are used in medical packaging. EVA based encapsulants are utilized to protect electronic components from moisture, vibrations and mechanical stresses.
Applications in Footwear and Wire and Cable jacketing
Ethylene vinyl acetate foams are used extensively in the manufacture of shoes, slippers and other footwear due to their shock absorption, soft texture and flexibility. Wire and cable jacketing applications utilize the flexibility, impact resistance, moisture barrier and adhesion properties of EVA to protect wires from mechanical and environmental damage. EVA also finds use as a binder in inks, coatings and tapes.
Use as a Thermoplastic Hot Melt Adhesive
EVA exhibits good hot melt adhesive properties and is widely used for production of disposable diapers, sanitary napkins, adult incontinence products and surgical drapes. The softness and flexibility of EVA polymers makes them ideal for use in these applications. Hot melt EVA adhesives maintain their bonds even when exposed to body heat and perspiration. 15-25% EVA is commonly utilized in these hot melt formulations.
Role in Medical Devices and Equipment
EVA finds increasing applications in the manufacture of medical devices due to its non-toxic and biocompatible nature. Implantable devices such as breast implants, hernia repair meshes and vascular grafts utilize ethylene vinyl acetate for its flexibility, impact strength and compatibility with body tissues over long periods. EVA tubing is used for medical equipment tubing and IV (intravenous) solution administration sets. Low smoke, non-toxic EVA formulations perform well in medical and hospital equipment manufacturing.
Other Applications
Some other applications that benefit from EVA properties include toys, sports goods, oil pipes, apparels, roofing, photovoltaic encapsulants, artificial turf etc. EVA provides an economical, durable and adaptable solution in these diverse applications. Future research will focus on extending the uses of sustainable ethylene vinyl acetate compounds, developing nano-engineered grades and exploring block and graft co-polymer versions with enhanced functionality.
To summarize, EVA is a versatile engineering thermoplastic with tailored properties useful across a broad range of markets. Its non- toxicity, flexibility, toughness, adhesion and processability make it a preferred material choice in applications as diverse as adhesives, footwear, medical devices, packaging films and cables. ongoing material innovations will likely expand its use.
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1. Source: Coherent Market Insights, Public Source, Desk Research
2. We have leveraged AI tools to mine information and compile it
About Author - Vaagisha Singh
Vaagisha brings over three years of expertise as a content editor in the market research domain. Originally a creative writer, she discovered her passion for editing, combining her flair for writing with a meticulous eye for detail. Her ability to craft and refine compelling content makes her an invaluable asset in delivering polished and engaging write-ups. LinkedIn
