Ethylene copolymers are widely used in manufacturing hot-melts adhesives and sealants because of their their mechanical cohesion and adhesive properties.
We distinguish 2 families of copolymers: ethylene vinyl acetate copolymers and ethylene acrylic ester copolymers.
All polymers are highly flexible products, compatible with many other polymers and additives, and are easy to process. They offer an excellent cost-performance ratio and are closely tailored to the requirements of the industry. Ethylene copolymer based hot-melts will present a very good adhesion on various substrates (such as paper, wood, plastics, metals...) and a broad operating window.
Ethylene vinyl Acetate
Ethylene vinyl acetate (EVA) is a co-polymer of ethylene and vinyl acetate. Depending on the amount of vinyl acetate present in the polymer, it can be classified into three types.
EVA copolymer which is based on a low proportion of VA (approximately up to 4%) may be referred to as vinyl acetate modified polyethylene. It is a copolymer and is processed as a thermoplastics material – just like low density polyethylene.
EVA copolymer which is based on a medium proportion of VA (approximately 4 to 30%) is referred to as thermoplastic ethylene-vinyl acetate copolymer and is a thermoplastic elastomer material.
EVA copolymer which is based on a high proportion of VA (greater than 60%) is referred to as ethylene-vinyl acetate rubber.
Hot melt adhesives (such as hot glue sticks) and top-of-the line soccer cleats are usually made from EVA, generally with additives like wax and resin. EVA is also used as a clinginess-enhancing additive in plastic wraps.
EVA is also used in biomedical engineering applications as a drug-delivery device.
EVA foam is used as padding in equipment for various sports such as ski boots, bicycle saddles, hockey pads, boxing and mixed-martial-arts gloves and helmets, wakeboard boots, waterski boots, fishing rods and fishing-reel handles. It is typically used as a shock absorber in sports shoes.
It is also used in the photovoltaics industry as an encapsulation material for crystalline silicon solar cells in the manufacture of photovoltaic modules.