What is a Hot Melt Adhesive?
A hot melt adhesive (HMA) is a 100% solids bonding agent applied in the molten state that forms bonds when cooling.
Its formulation always includes three main raw materials:
- Polymers are the backbone and provide cohesive or internal strength. They dictate the level of performance of temperature considerations and toughness, durability, and flexibility of the bond. Polyolefin are polymer materials made from small alkene monomers. EVA (Ethylene-Ainyl Acetate) are part of the oléfinic copolymers. It is mostly utilized in hot melt adhesive formulations, as a sealing film, and for bags to package frozen foods.
- Natural or synthetic tackifying resins.
- Plasticizers (mostly waxes and paraffin). These enable the adhesive to adapt to different open times and setting times.
In particular, rheology plays an important role in determining how they will perform for a specific application. Rheology relates to how well the adhesive will flow, wet out and adhere to a certain substrate. For example, elasticity, viscosity and modulus are related to its rheology.
- Elasticity is the adhesive’s ability to store energy and use that energy to retain original shape when moved.
- Viscosity is the adhesive’s resistance to flow.
- Modulus is the adhesive’s flexibility levels after it sets.
What are the benefits of EVA & Polyolefin Hot Melt Adhesives?
These adhesives offer the following benefits:
- Improved End of Life: They are able to replace solvent-based adhesives, offering compatibility with bio-based and renewable materials, which improves recyclability levels. They also offer a long shelf life and decreased adhesive consumption compared to other technologies, which reduces waste.
- Reduced Environmental Impact: Formulated with non-hazardous materials, they comply with strict regulations, minimizing volatile organic compounds (VOCs) and overall harmful emissions.
- Enhanced workability: They are low odor and can be easily sprayed, improving working conditions.
- Streamlined operational efficiencies: These adhesives don’t require stop-start operations, are fast setting and require little maintenance, which increases efficiencies and improves lean manufacturing.
- Enhanced design possibilities: EVAs and polyolefins can bond to multiple substrates, which increases design options.
- Increased safety: As a moisture-free bonding option, they reduce bacteria and virus contamination, allowing them to be able to be food grade and compatible with pharma white rooms.
What are Bostik's innovations about EVA & Polyolefin Hot Melt Adhesives?
Bostik’s sustainable hot melt adhesives improve production operations and end-use products across markets. Additionally, they are available in a high diversity of materials and colors. Here are some of our latest innovations:
- The Case and Carton Sealing Hot Melt Adhesive for High-Temperature Applications
Kizen HEAT is a sustainable hot melt adhesive solution for advanced high-temperature packaging applications. It is a water-white product designed for hot-filling applications, high-temperature storage of cases, carton sealing, and tray erecting. It resists thermal shock and temperature variations from 0°C to 70°C, even 80°C for specific cardboards.
- Compostable Adhesive for paper bags and industrial snacks (in the US)
THERMOGRIP 43298 hot melt adhesive can be used in paper cups and food services for to-go packaging applications. This adhesive passes industrial compostable standards as detailed in ASTM 6400-12 and is certified as meeting these criteria by BPI (Biodegradable Products Institute). These tests indicate Thermogrip 43298 to be a suitable adhesive component for compostable articles.
Contact us if you want to know more about our hot melt adhesive innovations.
What are the main applications of EVA & Polyolefin Hot Melt Adhesives?
For Consumer Goods, EVA and Polyolefin Hot Melt Adhesives, including Metallocenes, are appreciated for their multi-purpose, fast setting time, hot and cold temperature resistance, food safety compliance, and compatibility with difficult substrates. Hot Melt Adhesives improve efficiency and speed-up production by forming a bond quickly without needing time to cure or dry. They are mainly used for carton closing, box closing, wrap, trays, etc.
Why choose Kizen Force adhesive instead of conventional EVA and Metallocene for Case & Carton sealing?
Kizen Force adhesive provides similar performance as metallocene near the cost of EVA and can be foamed. The comparison of Kizen Force, EVA, and metallocene performances are given in the opposite graph.
Kizen adhesives also allow you to make considerable savings on your adhesive consumption. Calculate your savings.
Pulp & Paper
Bostik EVA and Polyolefins Hot Melt Adhesives, including Metallocenes adhesives, reduce environmental impact and increase operational efficiencies, design opportunities, performances, and quality.
THERMOGRIP 43298 is a high-performing compostable hot melt adhesive used for various paper and fiberboard packaging.
Building and Construction
Hot Melt Adhesives are mainly used in glass wool for roofing and woodworking (edge bonding and soft forming) in building and construction. These adhesives are suitable for a wide variety of substrates. Their non-VOC properties make them safe for use in buildings.
For the automotive and transportation industries, we offer APAO (Amorphous Poly-Alpha-Olefins) Hot Melt Adhesives. They are appreciated for their foamable compatibility, high heat resistance, UV resistance, and optimized viscosity for fast line speed, making them ideal for many applications in automotive.