INTERDIFFUSION OF FREE AND GRAFTED POLY(METHYLMETHACRYLATE) WITH POLYVINYLCHLORIDE, STUDIED BY INFRARED-SPECTROSCOPY

As a guide for adhesion development between two miscible polymers, int erdiffusion of these polymers was studied using external reflection an d attenuated total reflection infrared spectroscopy. Using gold substr ates coated with a double layer of PMMA and PVC, and s-polarized infra red light, PMMA features in the external reflection spectra increase u pon annealing at 150-degrees-C as a result of PMMA diffusion away from the gold substrate into regions with a higher electric field intensit y. Interdiffusion can also be followed with an external reflection set -up using glass substrates and p-polarized infrared light. Interdiffus ion of PVC and PMMA, free or grafted on a glass slide, was observed. I ncreasing the molecular weight of the PMMA slows down the interdiffusi on rate, which might be a consequence of a reduction in the thermodyna mic driving force for diffusion or the molecular weight of PMMA. Exter nal reflection spectroscopy as well as attenuated total reflection exp eriments show that interdiffusion of PVC and PMMA grafted on a silicon slide was much slower than that of free PMMA of similar molecular wei ght.