Emission of occluded volatiles during deformation of polycarbonate due to strain-enhanced diffusion
| Autor: | J. T. Dickinson, R. P. Dion, L. C. Jensen, S. C. Langford |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Polymers and Plastics
Chemistry Mineralogy Condensed Matter Physics Mass spectrometry Fick's laws of diffusion Volume (thermodynamics) visual_art Quadrupole Materials Chemistry visual_art.visual_art_medium Gaseous diffusion Physical and Theoretical Chemistry Deformation (engineering) Diffusion (business) Composite material Polycarbonate |
| Zdroj: | Journal of Polymer Science Part B: Polymer Physics. 32:993-999 |
| ISSN: | 1099-0488 0887-6266 |
| DOI: | 10.1002/polb.1994.090320604 |
| Popis: | Measurements of the emission of purposely entrained volatiles (Ar and D2O) during the loading and unloading of a bisphenol-A polycarbonate in vacuum are made by quadrupole mass spectrometry. Transient loading events are accompanied by dramatic increases in emission, reflecting a similar rise in the diffusion constant of the measured species. We attribute this change to an increase in size of molecular voids in the polymer network, which accompany the increase in sample volume under load. The results are interpreted in terms of the Dolittle relation in which the diffusion constant depends exponentially upon v*/vf0, the ratio between an activation volume for diffusion and the average size of the relevant voids in the polymer network. Our data suggests that v*/vf0 is unusually low in the D2O-polycarbonate system, which we attribute to a relatively large value of vf0; this would be consistent with the relatively long distance between flexible links in the polycarbonate structure. © 1994 John Wiley & Sons, Inc. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text