Diffusion and Permeability

Blister packaging systems are often used as a primary barrier to the ingress of moisture into moisture sensitive products such as those used in the pharmaceutical industry. These blister packaging systems often show substantial differences in barrier properties to the unformed polymer film due to localised defects/stresses in the polymer material as a result of the forming process. Their diffusion and permeability performance can be studied in great detail using the DVS method.

Application Note 12: Absolute Measurement of Moisture Diffusion into Blister Packaging Systems | Request a copy

The measurement of diffusion and permeation of vapours and liquids through real packaging devices is important for the development of both pharmaceutical and food packaging solutions. Typical requirements of these packaging systems are that the ingress and/or loss of moisture over long storage periods must be kept to a minimum in order to prolong the shelf life of the product.

Application Note 07: Measurement of Diffusion of Liquids and Vapors Through Real Polymer Tube Packaging Devices
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The microelectronics industry of the 21st century is under relentlessly increasing pressure to produce devices that are smaller, more powerful, more reliable and cheaper to manufacture. One key feature of many devices is the packaging system used to protect the device from physical damage and from environmental degradation of performance. Whereas hermetically sealed packages are the preferred solution for high-cost, high reliability applications such as avionics and defense, a more cost effective solution is required for consumer and industrial applications. The most common packaging solution used today is to encapsulate the device and the interconnection system in a thermosettable polymer resin. These can be studied at high temperatures and humidities using the DVS.

Application Note 31: Measurement of Moisture Ingress in Microelectronics Device Packaging | Request a copy

Moisture diffusion in thin polymer films is of interest to a variety of different industrial sectors including packaging materials and membrane technologies. The method used to calculate the diffusion constants for the thin films utilises diffusion equations first employed by Crank and Park. A thin film sample is suspended in the DVS and the sorption kinetics for a series of steps in humidity are recorded in the usual manner.

Application Note 30: Calculation of Diffusion Constants in Thin Polymer Films using DVS | Request a copy

Vapour permeability in porous materials is of interest to a variety of different industrial sectors including packaging materials, membrane technologies, tissue engineering scaffolds etc. This application note describes the measurement of moisture vapour transmission rates (MVTR) through porous materials (i.e. silicone membranes/human skin and electrospun polymer fibre mats), using a Payne type diffusion cell and DVS instrument.

Application Note 52: Vapor Permeability of Porous Materials using Payne Diffusion Cell | Request a copy

The moisture flux through various skin simulants and trypsinized human skin can be measured under different conditions, allowing the differences among them to be assessed. The effect of skin creams, for example, can be investigated by evaluating their ability to act as occlusives by observing their impact on Trans Epidermal Water Loss (TEWL) or moisture flux.

Application Note 56: Measuring TEWL or Moisture Flux Across Artificial Skin | Request a copy