Among the many hot melt adhesive film parameters, the melt index may not be familiar to the public. What is the significance of the parameters of the hot melt adhesive film? What guidance does it have for the use of hot melt adhesive films?
Melt index, also known as melt index (MI, melt index), is also called melt mass-flow rate (Melt mass-flow rate, referred to as MFR, melt mass flow rate). It is measured by a standardized melt-finger meter. During measurement, under a certain temperature and a certain pressure, the resin melt passes through a standard capillary, generally recording the number of grams of melt flowing out within 10 minutes; the unit is g/10min.
From the definition and measurement method of melt finger, it can be seen that the significance of melt finger is to evaluate the fluidity of hot melt adhesive film after melting. The higher the melt index of the hot-melt adhesive film, the better the fluidity of the hot-melt adhesive film after it is melted into the glue.
So after understanding the meaning of melt finger, how does it affect the use process of hot melt adhesive film? We know that the hot melt adhesive film with good fluidity after melting is more similar to a liquid, the glue liquid is easier to spread, and the permeability will be stronger. When we use a hot melt adhesive film with a high melt index, we need to use a smaller hot-pressing pressure and a shorter hot pressing time. On the contrary, when using a hot melt adhesive film with a low melt index, due to its poor fluidity, the glue is not easy to spread out, so we have to use a larger hot-pressing pressure and a long hot pressing time.
In addition to the melting range, the melting index of the hot melt adhesive film is another important parameter in the parameters of the hot melt adhesive film, which has a strong guiding significance for the use process of the hot melt adhesive film. Now everyone should know the importance of this parameter of melting the finger, right? If you have more questions about hot melt adhesive film, you can consult us.