Macroscopic yield in cavitated polymer blends
Macroscopic yield in cavitated polymer blends
复制标题
空化聚合物共混物的宏观产率
DOI：
10.1016/s0020-7683(00)00227-4
复制
发表时间：
2001
影响因子：
3.6
通讯作者：
V. Giessen
中科院分区：
文献类型：
--
作者：
K.G.W. Pijnenburg;V. Giessen
其中橡胶颗粒已空化的聚合物共混物可被视为多孔材料。Gurson模型可以很好地描述许多多孔介质的屈服行为。然而，聚合物的特征在于屈服前的大弹性应变。这些影响在原始Gurson公式中被忽略，如将显示的，这导致对空隙共混物的屈服应力的高估。聚合物塑性在窄剪切带中的局部化也导致偏离标准理论。本文提出了一个空洞的聚合物的二维细胞计算，并证明了整体的屈服特性不能很好地表示的Gurson势。这种潜力的修改，提出了考虑弹性效应和剪切带，并给出了更好的协议与细胞的结果。新的潜力推广到一个完整的三维连续模型的空隙聚合物共混物。
Polymer blends in which the rubber particles have cavitated may be regarded as porous materials. The yield behaviour of many porous media can be well described with the Gurson model. Polymers, however, are characterized by large elastic strains prior to yield. These effects are neglected in the original Gurson formulation, which, as will be shown, leads to an overestimation of the yield stress for the voided blend. The localization of polymer plasticity in narrow shear bands also results in deviations from the standard theory. This paper presents two-dimensional cell calculations of a voided polymer and demonstrates that the overall yield characteristics are not represented well by the Gurson potential. A modification of this potential is proposed that accounts for elasticity effects and shear banding and gives better agreement with the cell results. The new potential is generalized to a full three-dimensional continuum model for voided polymer blends.