Everything You Need to Know About Hot Melt Adhesives

Ogude hot melt adhesives deliver fast, robust bonding for a wide variety of substrates. These adhesives melt under high temperature and solidify upon cooling, suiting diverse materials and applications. Solvent-free, safe to handle and long-lasting, our hot melts are fully compatible with our complete range of hot melt glue guns. They reliably meet all your bonding requirements and deliver consistent bonding performance.

What Are Hot Melt Adhesives Made Of?

Hot melt adhesives contain no solvents and zero water. They set rapidly by dissipating heat. They enable reliable bonding between two non-porous materials.

• Polymers provide the adhesive with cohesive strength and moderate flexibility.
• Tackifying resins impart instant hot tack.
• Waxes reduce adhesive viscosity for smoother application.
• Antioxidants preserve adhesive performance under high-temperature conditions.

How Do Hot Melt Adhesives Work?

Hot melt adhesive is applied in a molten liquid state. Open time refers to the interval between adhesive application and joining the second substrate. Once the second material comes into contact, the adhesive cools and solidifies quickly. Adequate compression of substrates at this stage is critical for a sound bond.

Factors Affecting Bond Strength

Since hot melts cure via heat loss, application temperature is paramount. The adhesive must remain sufficiently molten to properly wet out substrates and reach the required temperature for assembly before cooling commences. If applied at insufficient temperature (not fully molten), a cold bond may form, prone to premature failure later.

Conversely, excessively high application temperature extends the molten state. The adhesive may stay soft even after compression ends. Any stress applied to the bondline will trigger immediate failure or degrade bond strength, leading to bonding failure over time.

Application Guidelines

1. Bonding substrates must be clean, dry and free of dust, dirt, oil and grease.
2. Hot melt adhesives shall be used at the recommended temperature range.
3. Substrate and ambient temperatures directly impact bonding results:
   • Excessively high temperature prolongs adhesive setting time.
   • Too low temperature causes the adhesive to solidify before substrates are joined.
4. Adhesive dosage greatly determines bond quality:
   • Insufficient glue cools too rapidly, preventing complete bond formation.
   • Excessive adhesive hinders cooling before compression is released, resulting in joint separation.