Hot-melt adhesives are widely used in crafting, packaging, manufacturing and repairs because of their speed, ease of use and versatility. Understanding the melting and application temperature of hot glue is key to choosing the right adhesive for a given job—and to achieving reliable, high-quality bonds. This article covers typical melting points and application ranges, explores factors that influence these values, and gives guidance on selecting glue for different materials.

Typical Melting and Application Temperatures

The melting point or “softening” temperature of hot-melt adhesives varies significantly depending on the polymer base, formulation and intended application. For example:

*Application temperature = the temperature at which the adhesive is melted and applied via gun or machine. It is higher than the solid softening point because it must reach fluidity and proper viscosity for bonding.

Therefore, when someone asks “what temperature does hot glue melt?”, the answer depends on the formulation, but for many standard types the range is roughly 120 °C to 200 °C (250-390 °F) for application, and softening or melting may begin at lower temperatures.

What Determines the Melting/Softening Temperature?

Several factors influence the melting or softening temperature of hot-melt adhesives:

• Polymer base: Common base materials include EVA (ethylene-vinyl acetate), PO (polyolefin), PA (polyamide), APAO (amorphous polyalphaolefin). Each has its own melt/softening temperature and physical properties.

• Tackifiers, plasticisers and waxes: These additives modify the melt viscosity, set time, adhesion behavior and temperature resistance.

• Crystallinity and molecular weight: More crystalline or higher-molecular-weight polymers typically raise the softening/melting temperature and improve heat resistance but may require higher application temperature.

• Intended service temperature and substrate: Adhesives may be formulated to remain solid under certain service (operating) temperatures; if the operating temperature of the bonded assembly is high, a higher-melting adhesive may be required. Additionally, the substrate may be heat-sensitive, forcing the use of a lower application-temperature adhesive.

Practical Implications for Use

When selecting and using hot melt adhesives, keep these practical considerations in mind:

• Substrate sensitivity: If bonding to foam, fabric, or thin plastic, a low-temperature hot melt (applied at ~120-130 °C) may be needed to avoid damaging the substrate.

• Bond strength vs. temperature: Generally, higher application-temperature adhesives allow stronger bonds and better high-temperature performance. However, if applied too hot, they may damage substrate or cause char/overheating.

• Heat resistance of final bond: A hot glue that begins softening at, say, 80 °C may fail under continuous high-temperature service conditions. So the softening point must exceed the expected service temperature.

• Processing equipment and safety: Application equipment (glue guns, bulk melters) must reach and maintain the required temperature for the adhesive. Operators should be aware that hot melts can burn skin and damage materials.

Temperature Ranges - Quick Reference

Here is a quick reference table summarizing common application temperature ranges:

Choosing a Supplier and Product

If you require dependable hot melt adhesives for industrial or manufacturing use, it is advisable to partner with a reputable and technically capable supplier. For example, HUACHUN, a manufacturer of hot-melt adhesives since 1998, offers an extensive range of hot melt glue sticks, blocks and pellets, including types for low temperature, high temperature, and specific substrate bonding. On their website they highlight strong productivity and high quality raw materials.

When engaging with a supplier like HUACHUN, consider specifying:

• The substrate(s) you are bonding (e.g., wood, cardboard, plastic, metal)

• Service temperature requirements (maximum continuous and peak)

• Application temperature constraints (to avoid substrate damage)

• Desired bond strength and set time

• Format of adhesive (sticks, pellets, blocks) and compatibility with your equipment

Summary

In summary, although the melting or softening temperature of “hot glue” depends significantly on its formulation, most common hot melt adhesives are applied in the temperature range of roughly 120 °C to 200 °C (250-390 °F). Low-temperature variants may melt and be applied at lower temperatures (~100-130 °C) to protect heat-sensitive substrates, while high-temperature types may require application at 180 °C or higher for enhanced bond strength and heat resistance. Matching the adhesive’s application and service-temperature performance to the substrate, process and environment is essential for a reliable bond. Choosing a quality supplier such as HUACHUN ensures access to the proper formulations as well as expert material-matching support.