Inelastic behavior of polymers under multiaxial compression

聚合物在多轴压缩下的非弹性行为本程序的目标是研究聚合物材料在压力在1 Gpa范围内的多轴压缩下的非弹性响应。以聚碳酸酯、聚甲基丙烯酸甲酯和聚乙烯为例进行了研究。这些聚合物在弹性、非弹性和粘弹性响应中表现出显著的压力敏感性。这些在技术上也是非常重要的聚合物，非常用于商业用途。该方案提出的主要创新是一种新的约束压缩实验方案，其中所有的应变和应力分量都得到了仔细的测量。由此产生的变形在宏观上是均匀的，在几何上是稳定的。初步实验表明，该配置达到了预期的效果。在这种构型下，建议研究上述三种聚合物的初始弹性系数、多轴载荷下的屈服行为和非弹性行为以及线性粘弹性行为的压力依赖性。应该指出的是，拟议的实验是“干净的”实验，因为在解释实验结果时没有嵌入任何关于材料行为的假设。因此，这些结果可以用来检验许多关于聚合物行为的机制理论和现象学理论。

Inelastic behavior of polymers under multiaxial compression 0072195The objective of this program is to investigate the inelastic response of polymeric materials under multiaxial compression, with pressures in the range of 1 GPa. Polycarbonate, polymethylmethacrylate and polyethylene are take to be examples to be examined. These polymers exhibit significant pressure sensitivity in their elastic, inelastic and viscoelastic response. These are also technically very important polymers, very much in commercial use. The main innovation presented in this proposal is a new experimental scheme of confined compression, where all the strain and stress components are carefully measured. The resulting deformation is macroscopically homogeneous and geometrically stable. Preliminary experiments have shown that the configuration works as expected. With this configuration, it is proposed to examine the pressure dependence of the initial modulus, yielding and inelastic behavior under multiaxial loading, and linear viscoelastic behavior of the three polymers listed above. It should be noted that the proposed experiments are "clean" experiments in the sense that no assumptions regarding the material behavior are embedded in interpreting the experimental results. Thus, the results can be used to provide checks on the many mechanistic as well as phenomenological theories of polymer behavior.