论文标题
拉伸聚合物玻璃的应力和介电敏感性中的同时记忆效应
Simultaneous memory effects in the stress and in the dielectric susceptibility of a stretched polymer glass
论文作者
论文摘要
我们报告了实验证据，表明以恒定应变速率$ \dotλ$拉伸的聚合物在此之后呈现复杂的内存效果，以$ \dotλ$设置为零，以特定的应变$λ_W$在持续时间内$ t_w $，范围从$ 100 $ s到$ 2.2 \ $ 2.2 \ times10^5 $ s。当应变速率恢复时，应力和介电常数均在非单调的情况下放松到未扰动的状态。放松取决于可观察到的$λ_W$和$ t_w $。放松主曲线是通过将放松时间缩放为$ t/\ ln（t_w）$来获得的。介电演化还捕获了放松时间的分布，因此结果对聚合物在压力下的放松模型施加了强烈的限制，它们对于更好地理解其他疾病材料的记忆效应很有用。
We report experimental evidence that a polymer stretched at constant strain rate $\dotλ$ presents complex memory effects after that $\dotλ$ is set to zero at a specific strain $λ_w$ for a duration $t_w$, ranging from $100$s to $ 2.2\times10^5$s. When the strain rate is resumed, both the stress and the dielectric constant relax to the unperturbed state non monotonically. The relaxations depend on the observable, on $λ_w$ and on $t_w$. Relaxation master curves are obtained by scaling the relaxation time as $t/\ln (t_w)$. The dielectric evolution also captures the distribution of the relaxation times, so the results impose strong constraints on the relaxation models of polymers under stress and they can be useful for a better understanding of memory effects in other disorder materials.
