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Viscosity of elastomeric impression materials.

T W Herfort·W W Gerberich·C W Macosko·R J Goodkind
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Abstract

(1) Some elastomeric impression materials (Omniflex and Impregum) exhibited extreme shear thinning properties. This property was considered useful and these materials can be considered all-purpose. (2) The use of impression materials in syringing applications should not be precluded simply because the substances are thick or heavy during spatulation. A tenfold reduction in viscosity with increasing shear rate was found for three of the materials tested. (3) Viscosity characteristics of the impression rubbers were linked to filler content. (4) The viscosity rise during cross-linking was monitored for various impression products. It was found that each manufacturer's specifications of the length of time for syringing were relatively accurate.

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Chemical PhenomenaChemistry, PhysicalDental Impression MaterialsRheologySilicone ElastomersViscosityJournal Article

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T W Herfort, W W Gerberich, C W Macosko, R J Goodkind. 1977. Viscosity of elastomeric impression materials.. https://doi.org/10.1016/0022-3913(77)90093-2

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