What should be paid attention to during hot melt glue production?

Hot melt glue production involves steps such as heating, melting, shearing and dispersing, and sealing and packaging. To ensure consistent quality and production safety, JCT has listed the following key points that must be focused on.

Ⅰ. Safety Precautions

1. High-temperature operation risks

The melting temperature of hot melt glue is generally between 120-180℃.

Operators must wear protective gloves, safety glasses, and protective clothing.

Avoid direct skin contact with the molten adhesive to prevent burns.

2. Equipment sealing and pressure control

Sealed reactors or sigma mixers must have their seals, pressure gauges and safety valves checked regularly.

Never operate under excessive pressure to prevent leaks or explosions.

3. Ventilation and exhaust gas emissions

Trace amounts of fumes may be generated during production.

An exhaust system and filtration device are required.

Maintain good air circulation in the workshop.

Ⅱ. Raw Material Considerations

1. Raw material purity and moisture content

EVA, SIS, SEBS, and tackifying resins must have low moisture content.

Excessive moisture content will cause foaming, increased gel point, and unstable viscosity.

2. Storage conditions

Raw materials should be stored away from light, in a dry place, and in sealed containers.

Tackifying resins are hygroscopic; use the first opened portion first.

Liquid additives such as antioxidants require precise measurement.

Ⅲ. Production Process Precautions

1. The order of material addition should not be changed arbitrarily

The usual order is: base material → tackifying resin → wax → additives.

Incorrect order will lead to uneven dispersion, abnormal gel point, and viscosity fluctuations.

2. The temperature profile must be strictly controlled

Excessive heating rate → easy charring and smoke generation.

Excessive temperature → thermal oxidation and darkening of color.

Excessive temperature → affects viscosity and solubility.

Ⅳ. Equipment Usage Precautions

1. The inner wall of the reactor needs to be cleaned regularly

To avoid charring of colloid residue.

To prevent cross-contamination between different formulations.

2. Stable heating system

The heat transfer oil temperature should be uniform, with no open flame heating.

The temperature control system must be sensitive to avoid temperature drift.

3. Select the correct discharge method

Sheeting

Lower discharge pump conveying

Die granulation

Different discharge methods require different equipment layouts.

Ⅴ. Quality Control Precautions

1. Key testing items

• Viscosity
• Softening point
• Initial tack/holding power
• Color
• Sealing performance
• Stability (heating aging test)

2. Enhanced online monitoring

• Equipment flow meter
• Temperature rocording
• Stirring power changes (to determine if dissolution is uniform)

Ⅵ. Common Problems and Prevention

JCT is professional hot melt glue production line turnkey project provider. We will help you start hot melt glue production in one-stop! feel free to chat with us for more information: +86-18138373963 (Whatsapp, Wechat) or jctmixing@outlook.com.