Materials Science and Technology of Polymers
Marcin Debowski, University of Twente, Faculty of Chemical Technology
Morphology of Filled Elastomers via Atomic Force Microscopy (AFM). Fine.particle precipitated silica has been used as an active, reinforcing filler for many years, however, its wide application in one of the most obvious and promising areas . the tires production, has been limited for a long time due to a number of disadvantageous properties including the strong filler.filler and weak rubber.filler interactions. These problems could be circumvented by using specifically designed organosilanes as coupling agents. The silica filler treated with such reagents can be significantly better dispersed in the rubber matrix. The dispersion of various fillers in rubber has been determined predominantly by optical and electron microscopy. More recently atomic force microscopy (AFM) was also applied to the visualization of rubber morphologies and to studies of silica and carbon black micro.and nanodispersions. Outstanding flexibility and usefulness of this modern technique was utilized many times to solve or elucidate a wide range of phenomenon related to rubber multicomponent systems. The most obvious and already mentioned application is the determination of filler particles distribution. Using AFM phase.imaging one can clearly distinguish between the filler particles and the surrounding rubber matrix. This provided insight can be very helpful and supportive for explanation of many macroscopic, namely mechanical relations. For numerous rubber systems a distinctive morphology has been recorded. In this lecture the representative examples of differences in silica distribution for various unvulcanised rubber compositions will be shown. Different elastomers and different types of silica, both modified with silane coupling agents and these based on raw, unmodified silica filler were used. Various morphological features characteristic for multicomponent elastomeric systems will be also presented.