Physical/chemical analyses

DSC is a technique for determining the composition of foils or raw materials. Using this technique, we examine what happens when polymer is heated and is cooled down again (thermal transition). During the application of this technique, heat flows to and from the sample are measured in which the test sample and a reference go through a precisely set temperature curve. Using this technique, we can determine the melt, crystallisation or glass transition, for example.

This technique is used to determine the IR spectrum of raw materials or foils from which the global composition can be determined. Infrared spectroscopy is based on the vibration frequencies of the chemical bonds. The IR spectrum is recorded by shining a fine beam of infrared light through a sample. The presence of the various molecules in the sample and their variety of bonds provide the absorption of the infrared light at characteristic frequencies.

This versatile technique is used to determine foil composition, distribution of layer thickness, inclusions, impurities, etc. Raman spectroscopy is a spectroscopic technique used to study the vibrations and rotations in molecules. Raman spectroscopy is based on the inelastic dispersion – i.e., Raman dispersion – of monochromatic light. Raman spectroscopy uses a laser as light source in visible light, ultraviolet light or nearby infrared light.

The Melt Flow Index is a measure of the flow of plastics. This property is especially relevant for extruding plastic. The basic principle is based on the fact that a thermoplastic sample (often granulates) is liquefied by heating it and subsequently, the liquid thermoplastic sample is pressed through an extruder die head.

The OTR determines the oxygen permeability of a foil: it measures how much oxygen goes through a foil in a certain period and under certain conditions.

The WVTR determines the water vapour permeability of a foil: it measures how much water vapour goes through a foil in a certain period and under certain conditions.