MECHANICAL-BEHAVIOR AT LOW STRAIN OF MICROGEL CONTAINING ELASTOMERS

Synthetic routes for the preparation of microgels with defined particl e size, crosslinking density and surface chemistry are described. The mechanical effects caused by incorporating such systems in crosslinked rubber (NR and SBR) are described. The mechanical effects are qualita tively related to the state of clustering which is governed by the par ticle size and the interfacial tension (delta-parameter difference). T he reinforcing effects on Young's modulus and the dynamic shear modulu s are explained against a comprehensive theoretical background which a ssumes kinetically controlled cluster-cluster aggregation (CCA) of col loidal filler particles dispersed in entangled polymers. This leads to a control of rubber material properties by chemical means.