Design of a rapid characterization method to predict the sealing behaviour of LLDPE packaging films

The aim of the research was to develop a test method that allowed to determine the sealing window of materials at an early stage of the development process. It was found that heating and cooling rates encountered during production and sealing of the materials were high. However, in existing methods to predict the seal strength, these high rates were often not considered. Therefore, a new method has been proposed using flash DSC measurements. The sealing window was predicted for two different LLDPE films, based on the studied melt behaviour of the materials. Melting and subsequent recrystallization within the material indicated chain mobility, which was related to the sealing window. It was found that the melting temperature of the materials were dependent on the heating rate and that the melting point determined the end of the sealing window.