Study of Multicomponent Diffusion in Polymers Using FTIR-ATR Spectroscopy
Abstract
The specific aim of this project was to study the diffusion of complex mixtures, some of which are capable of self-association and solvation, in polymers. The focus was primarily on rubbery polymers, but a glassy polymer was also studied. Diffusion coefficients were measured with FTIR-ATR spectroscopy, a powerful technique that can monitor individual components in a mixture and can also detect association or solvation interactions through changes in the infrared spectrum. Transport equations that incorporate these interactions were developed and tested. The following systems were studied: (1) the diffusion of pure methyl ethyl ketone (MEK) and MEK/toluene mixtures at various vapor phase activities in polyisobutylene (PIB), (2) the diffusion of acrylonitrile from the liquid phase in conformational isomers of a polyurethane, (3) the diffusion of methanol in glassy polycarbonate, and (4) the diffusion of methanol and ethanol in polybutadiene as a function of temperature. In addition to the experimental measurements, mathematical models were developed to determine the effect of association and solvation on the transport of small molecules in polymeric sorbents and barrier materials.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2000
- Accession Number
- ADA384781
Entities
People
- Timothy A. Barbari
Organizations
- Johns Hopkins University