Characterization of the Interface in Polymer-silica Composites Containing and Acrylic Silane Coupling Agent
Microscopic dynamics of the interfacial layer and macroscopic mechanical properties of [3-(acryloxy)propyl]trimethoxysilane (APMS) at a polymer−silica interface were studied using NMR and three-point bending tests. Wide-line deuterium NMR studies of deuterium-enriched [3-(acryloxy)propyl]trimethoxysilane-d (APMS-d), showed that when chemically bonded to silica, the acrylic group of APMS moved rapidly at the interface with air, more slowly when coated with a poly(methyl methacrylate) (PMMA) overlayer, and slowest when copolymerized with methyl methacrylate. A two-component line shape was found for the coated composite and these were assigned to relative immobile and mobile surface groups. From three-point bend tests, the PMMA/glass-fiber composite, made from glass laminates treated with APMS, had almost two times the flexural strength of a composite made from glass laminates not treated with APMS. Electron micrographs of the fracture surfaces revealed that the untreated fibers were smooth, while those from the APMS-treated glass were rougher, indicating the presence of polymer at the interface.
H. Jo and F. D. Blum, "Characterization of the Interface in Polymer-silica Composites Containing and Acrylic Silane Coupling Agent," Chemistry of Materials, American Chemical Society (ACS), Jan 1999.
The definitive version is available at http://dx.doi.org/10.1021/cm9902570
National Science Foundation (U.S.)
Article - Journal
© 1999 American Chemical Society (ACS), All rights reserved.