Strength of Elastomers. A Perspective
Strength of Elastomers. A Perspective
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弹性体的强度。
DOI：
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
T. L. Smith
中科院分区：
文献类型：
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作者：
T. L. Smith
弹性体的强度和延展性取决于其总体粘弹性，如应力-应变曲线的时间和温度依赖性所反映的，也取决于那些离散的过程，包括裂纹的形成和生长，最终导致高速裂纹扩展。离散过程决定了试样的寿命;粘弹性特性影响应力对变形的依赖性。这些效应之间的相互作用导致强度和延展性强烈依赖于测试条件。仅由高度移动的链组成的弹性体网络实际上非常弱，并且在低伸长率下断裂。这种特性与理想的移动的链网络的预期特性完全不同。如果这样的网络被拉伸，应力集中和分子水平上的不平衡力，这可能是由短链，缠结和网络缺陷引起的，将被应力偏置的节段扩散迅速破坏。
Abstract The strength and extensibility of an elastomer depend on its overall viscoelastic properties, as reflected in the time and temperature dependence of stress-strain curves, and also on those discrete processes, including crack formation and growth, that culminate in high-speed crack propagation. The discrete processes determine the lifetime of a specimen; the viscoelastic characteristics affect the dependence of stress on deformation. The interplay between these effects causes strength and extensibility to depend strongly on test conditions. An elastomeric network composed solely of highly mobile chains is very weak indeed and fractures at a low elongation. This characteristic differs diametrically from that expected of an idealized network of mobile chains. If such a network were stretched, stress concentrations and unbalanced forces at the molecular level, which can result from short chains, entanglements, and network imperfections, would be vitiated rapidly by stress-biased segmental diffusion, ...