| Abstract: | The sorption of methylene chloride in neat PEEK was investigated as a function of temperature, sample thickness, surface treatment, and thermal history. The solubility of H2CCl2 in neat PEEK is 23 wt.% and is independent of thickness. Both surface treatment and thermal annealing strongly affect the rate of penetration; the as-Received material sorbs H2CCl2 more rapidly than abraded or annealed samples; however, the bulk solubility is independent of surface treatment. The sorption and desorption processes are considerably different, and the diffusion process is not simple Fickian Case I. The penetrant advances as a sharp front, suggesting a two-step, relaxation-controlled diffusion mechanism. |
