Effect of Particulate Fillers on the Rheology of Polymer Melts
Abstract
This work focuses in the basic understanding of reinforcement and the relationship between the morphology of the material and its rheological behavior. Mixtures of polydimethylsiloxanes and different fumed silicas were tested under oscillatory shear. The silica structure was kept constant by using a single initial product. Only the surface chemistry was changed. All samples showed a strong strain dependence, and the frequency dependence changed dramatically with silica concentration. Agglomeration increases with silica concentration, amount of silanols on the silica surface and polymer molecular weight. All these observations as well as the relaxation of the different materials are explained with a model in which agglomeration takes place through intermediate chains that link the aggregates to one another. However, low molecular weight suspension showed a different behavior. This behavior was related to the absence of entanglements and low probability of bridging chains. Keywords: Polydimethylsiloxane, Silica filler, Rheology, Fluid mechanics, Polymer melts, Elastomers and rubbers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 25, 1990
- Accession Number
- ADA223601
Entities
People
- Christopher W. Macosko
- Elsi Mora
- Mirta. I. Aranguren
Organizations
- University of Minnesota