Hot melt adhesive is a plastic polymer adhesive. Within a certain temperature range, its physical state will change with temperature. EVA hot melt adhesive is an environmentally friendly chemical product. When in use, sometimes the hot melt adhesive may be pulled out after melting. It affects the work efficiency and the beauty of the product. So, what is the reason for the wire drawing after the hot melt adhesive is melted? This is mainly caused by the following factors.
1. Cohesive strength of hot melt adhesive
The cohesive force and drawing effect of hot melt adhesive are basically: the cohesive force is large, and the drawing phenomenon is obvious; on the contrary, the cohesive strength is low, and the drawing phenomenon will not occur.
2. Curing time of hot melt adhesive
The curing time of the hot melt adhesive is very important for the occurrence of wire drawing. Generally speaking, the hot melt adhesive with short curing time has a low drawing rate, because the filament formed after the hot melt adhesive is cured cannot continue to be stretched, and it is prone to breakage, and sometimes it is not even drawn out.
3. Rheology of molten hot melt adhesive
The rheology of the molten hot melt adhesive has a decisive influence on the drawing, which is related to the design of the hot melt adhesive formula, the selection of materials in the formula, and the composition.
4. The influence of machine temperature
If the temperature is too low, the thinness of the glue itself will increase, and there will be a wire drawing phenomenon.
The above are several reasons for the drawing phenomenon of EVA hot melt adhesive. If the above phenomenon occurs during operation, it must be dealt with in time.
