Effect of External Stress on the Transport of Fluids in Thermoplastic Resin Systems.
Final rept. 1 Mar 93-28 Feb 94,
MICHIGAN MOLECULAR INST INC MIDLAND
Pagination or Media Count:
The transport properties of liquid penetrants into the thermoplastic resin, poly aryl ether ether ketone were investigated. The primary objective of this work was to study the effect of external applied stress on the diffusion and solubilityswelling of fluids with PEEK. The solubility and rate of penetration, i.e., diffusion, into the resin system are greatly increased by the application of stress we call this phenomenon SEDS stress enhanced diffusion and solubilityswelling. All eight fluids studied, benzene, toluene, methylene chloride, chloroform, carbon disulfide, methanol, acetone, and even water exhibit SEDS. The effect is particularly striking for crystalline PEEK where the solubility is markedly increased and the time to reach saturation, i.e., the induction period is reduced when the applied stress exceeds a critical value. For example, at 22C the solubility of toluene into 29 crystalline PEEK increases from 9 wt to almost 40 wt upon the application of a tensile stress of 35 MPa. Furthermore, the time for 0.25 mm thick crystalline PEEK film to reach its saturation value was reduced from 1000s of hours to less than 10 hours.
- *STRESS ANALYSIS
- *TRANSPORT PROPERTIES
- *THERMOPLASTIC RESINS
- *FLUID FLOW
- *AEROSPACE CRAFT
- CARBON DISULFIDE
- ARYL ETHERS
- LIFE EXPECTANCY(SERVICE LIFE)
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