When choosing hot melt adhesive film products for compounding, we usually need to consider the temperature parameter. At this time, we will encounter two types of hot melt adhesive film products: high-temperature hot melt adhesive film and low-temperature hot melt adhesive film. So which one is better, high-temperature hot melt adhesive film and low-temperature hot melt adhesive film? What are their characteristics?
Features of hot melt adhesive film
It needs to be heated and melted to have viscosity, and it will have adhesive strength after cooling and hardening. The high-temperature hot-melt sticky film, as its name implies, needs to be heated at a high temperature. On the contrary, the low-temperature hot-melt adhesive film can be heated and melted under low-temperature conditions.
Because the hot melt adhesive film will melt when it reaches a specific temperature, after melting, even if a good bond has been formed in the early stage, it will lose the bond strength again. Therefore, the melting temperature of the hot melt adhesive film is close to its temperature resistance temperature. If this temperature is exceeded, the hot melt adhesive film will lose its adhesion.
Therefore, under normal circumstances, the temperature resistance of our high-temperature hot melt adhesive film is also relatively high; on the contrary, the high-temperature resistance of the low-temperature hot melt adhesive film is also rather poor. For example, one of our TPU hot melt adhesive films is used at a temperature of 150°C, and its temperature resistance is usually around 60°C; and another EVA hot melt adhesive film, its use temperature is 100°C, and its temperature resistance is usually 40°C. ℃ or so.
It is worth mentioning that the melting temperature is different from the actual use temperature of the hot melt adhesive film, as you can see from the above example. The actual use temperature of hot melt adhesive film is usually several tens of degrees higher than the melting temperature. The specific height also depends on other characteristics, such as the melt index of the hot melt adhesive film itself, in order to make the hot melt adhesive film melt in a shorter time.
Through the above description, we seem to feel that the high-temperature hot melt adhesive film has better performance advantages and can be compounded on more demanding occasions. But in fact, this is not the case. In our material bonding applications, not all occasions need to put forward high-temperature resistance requirements for hot melt adhesive films, and often low-temperature hot melt adhesive films can meet the performance requirements. In addition, the use of low-temperature hot-melt adhesive film can greatly reduce energy consumption. On the basis of meeting the performance requirements, try to be energy-saving and environmentally friendly. This is what we pursue.
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