PUR hot melt adhesive (Polyurethane Reactive) is a new type of one-component, solvent-free hot-melt structural adhesive. It is cured by moisture in the air and has excellent bonding strength and impact resistance after complete curing. It also has With excellent bonding strength, temperature resistance, chemical corrosion resistance and aging resistance, it has become the best adhesive for bonding in electronic industries such as mobile phones in recent years.

Factors and solutions that affect the production process during the gluing process of the product:

1. Influence of chemical composition of PUR hot melt adhesive

The amount of certain chemical components of PUR hot melt adhesive directly affects the viscosity of PUR. From the perspective of product performance, we must choose a suitable glue.

2. The influence of different bonding materials

PUR hot melt adhesive has good bonding ability to different base materials, such as rubber, plastic, glass, metal, leather, wood, fabric, etc. For different bonding materials, choose the appropriate glue model.

3. The amount of glue applied

The amount of PUR adhesive layer applied will affect the curing time. If the adhesive layer is thin, the curing time will be short. When the amount of glue applied is large, the moisture content of the cured glue will be relatively insufficient, and the curing time will be longer, which will ultimately affect the bonding strength of the structural parts.

4. Dispensing opening time

The specific time for the PUR hot melt adhesive applied on the sample to be exposed to the air should be based on the parameters of the adhesive. Generally, within one minute or less, the composite bonding effect is optimal. Complete the bonding within the effective opening time to prevent the glue line from drying out due to too long opening time, resulting in poor wetting effect of the glue line and thus affecting the strength of the bond.

5. Pressing

The structural parts after assembly with PUR hot melt adhesive must be pressed together, the time should be no less than 15 seconds, and the pressure should be no less than 3 kg. The purpose is to make the glue form a good glue thickness and glue wetting effect between the two bonding surfaces.

6. Ambient temperature and humidity

PUR hot melt adhesive is cured by moisture in the air. If the ambient humidity is high, the curing time will be short. On the contrary, if the time is long and the ambient temperature is high, it is conducive to the participation of moisture in the reaction, and the curing time will be shortened accordingly.

7. Adhesive surface treatment

Removing oil, dust, paint, release agents, oxide layers and other substances that affect bonding on the surface of the bonded parts will help enhance the bonding effect of PUR hot melt adhesive.

1. PUR hot melt adhesive for fabric bonding

It can greatly reduce the labor intensity of clothing through bonding and stitching, and the high-imitation clothing made is good, well-fitting and strong. Hot melt adhesives used for fabric bonding mainly include polyamides, polyphenols and polyurethanes.

2. PUR hot melt adhesive for lining processing

The adhesive lining is made by the surface of the fabric on the surface of the fabric. In use, the adhesive backing fabric is cut into the desired shape and size, and the side on which PUR hot melt glue is applied is thermally bonded to the back of the other fabric material. It is arranged on the high imitation clothing layer and serves as the skeleton of high imitation clothing, simplifying the handling and time of high imitation clothing, making high imitation clothing lightweight, beautiful, comfortable, retaining shape, washable, and durable. Interlining processing generally requires hot melt adhesives to be colorless, odorless, soft, fast, dry and moisture-resistant, and the adhesive does not affect the fabric and is light-resistant.

3. PUR hot melt adhesive for carpet bonding

Carpets used for PUR hot melt adhesives are mainly copolymers of ethylene and other olefinic monomers, such as ethylene-vinyl acetate copolymer, ethylene acrylate copolymer, etc. In most cases, ethylene-vinyl acetate copolymer (EVA) is used.