Dynamics of Acrylate and Methacrylate Polymers on Surfaces

摘要

Acrylate and methacrylate polymers are used in a variety of applications, both as pure polymers and as components of composite materials. It is hoped that information about the molecular motion of the polymers in the solid support/polymer interfacial region will aid in the development of new composite materials and in the understanding of their properties. Some results of CP-MAS NMR studies of poly(isopropyl acrylate) (PIPA) and poly(methylmethacrylate) (PMMA) will be discussed. We have studied the adsorption of poly(isopropylacrylate) (PIPA) on surfaces of Cab-O-Sil silica (type M5) and find monolayer coverage to be c.a. 250 mg PIPA/g silica. We have examined the cross-polarization/dipolar decoupling/magic angle spinning (CP/DD/MAS) of this material in bulk and as a function of coverage on the surface. It is found that more highly resolved spectra are found on the surface than in bulk. This appears to be due to the relatively fast motion of the polymers which effectively negates the dipolar decoupling in the bulk sample. Reprints. (AW)