diffusion of butane in polypropylene  


Posted by Suneetha Burla on February 02, 2005 at 16:56:18:

I need some information regarding the following topics:

1. Diffusion of liquids and gases through thermoplastic polymers. The temperature at which diffusion occurs would be below the polymer glasstransition temperature. In other words, the polymer is glassy. The polymer may be amorphous or semicrystalline. Candidate polymers of interest are polypropylene and polyacrylonitrile. Candidate diffusing molecules are butane gas and hexane as a liquid. Also, water and alcohol. Diffusion could be Fickian (case I) or non-Fickian (case II).

2. What are the most common experimental and analytical techniques used to determine diffusion and chemical resistance (including mechanical degradtion) behaviour? How does one analyze the data? How does one compute solubility, diffusivity and permeability?

3. What theories can be used to correlate and predict diffusion through polymers? Can we do any accelerated experiments?

4. What happens to the polymer (i.e. what physical and chemical
structural chages occur and why) when glassy polymers or rubber gaskets come in contact with hydrocarbon gases and liquids? What happens when they come in contact with water or alcohol containing either fragrences or insecticides?

5. Diffusion of a liquid through a polymer film when the liquid
contains two dissolved liquid solutes.


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