Microwave irradiation effect on diffusion of organic molecules in polymer

Microwave irradiation effects on diffusion of some small organic molecules in polyethylene, polyvinylchloride, and silicone rubber were investigated using general weight-gain method. To eliminate the development of hot spots and inhomogeneous temperature distribution that occur often during microwave heating, sorption/diffusion solutions were well mixed with a magnetic stirrer at atmospheric pressure. The deviations of the diffusion rates between microwave and conventional diffusions were shown to be below 2.1%. This result reveals that previously reported nonthermal effects of microwave to promote diffusion do not exist in the examined diffusant/polymer systems.