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Abstract

When the temperature of an elastomer exceeds a critical value, there can be scission and recrosslinking of molecular chains and the formation of new molecular networks. These events are time and temperature dependent. When this happens in a deforming elastomer, there can be permanent set and modified mechanical properties. A constitutive theory has recently been proposed that accounts for these continuous changes in microstructure. Several analytical results are presented in this paper for materials that are described by this theory. First, several motions and associated temperature distributions are presented that are possible in every material described by the constitutive theory, independent of material properties. Second, when the temperature of an elastomer increases beyond the critical value and then decreases below it, scission and re-crosslinking stops and the resulting material exhibits modified elastic response. The constitutive equation for the modified elastic response is developed from the underlying constitutive theory, and the associated material anisotropy is discussed. Lastly, special results are obtained when the original and newly formed networks can be described as neo-Hookean.

Keywords

elastomers scission and healing controllable motion induced anisotrophy permanent set

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Some Comments on the Mechanical Response of Elastomers Undergoing Scission and Healing at Elevated Temperatures

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