Elastic Modulus and Swelling of Butyl Vulcanizates

On the mechanism of strain energy storage in silica reinforced silicone elastomers

“…It has been commonly observed (1.2) that the addition of finely-divided silica markedly enhances the mechanical behavior of silicone vulcanizates; these improvements are known as reinforcement. Earlier works (3,4) have shown that modulus reinforcement was closely associated with an increased enthalpic energy component of the retractive force for both silica and carbon filled rubbers. This communication w i l l show that a similar correlation also exists for the tensile reinforcement of silicone rubber.…”

Rheology of Filled Siloxane Polymers

“…Zapp and Guth (17) showed that swelling of butyl polymer containing fillers served to break bonds to the less active mineral fillers while those to carbon black were not broken. In effect, reinforcing fillers (or active ones) are those capable of forming bonds to polymer molecules which are not broken by low shearing stresses or by swelling in solvents of maximum swelling power for the polymer concerned.…”

Aging Stability of Neoprene Latex. Relation Between Crosslinking and Hydrolysis of Allylic Chlorine

“…The addition of a clay filler causes a large over-all rise in the tensile strength without a corresponding rise in the number of crosslinks measured by swelling. Such a result would be produced through the destruction of bonding forces between polymer and clay by the spreading action of the absorbed solvent (33).…”