A Multi-Scale Approach for Understanding the Role of the Interphase in Polymer Matrix Composites

研究的重点是多尺度（分子-纳米-微米）研究界面相及其与聚合物基复合材料（PMC）性能的关系。该研究的第一个目标是在聚合物固化周期中实时监测相间区的化学成分。第二个目标是测量作为硅烷偶联剂表面处理函数的界面的尺寸和机械性能。第三个目标是测量模型PMC系统的微观力学性能。几个任务涉及到满足研究目标。第一个任务将涉及使用新型傅里叶变换红外光纤传感器系统对模型聚合物进行原位反应监测，该系统允许直接监测相间化学。实验将在未改性的玻璃纤维上使用聚合物/固化剂混合物，并在高温下随时间进行多汞化。接下来，将对玻璃纤维进行硅偶联剂表面处理，并与固化剂/聚合物反应性同时测定有机功能反应性。研究的第二个任务是表面处理和聚合物固化后的纳米力学性能表征。原子力显微镜和纳米压痕将用于表征相间区域。这些结果将与第一个任务的现场红外数据相关联，特别是有机功能反应性和聚合物固化对所得界面性质的作用。第三项任务将涉及通过使用微键测试方法测量模型PMC的微观力学行为。在这部分研究中获得的结果将与上面提到的前两个任务相关。

The focus of the research is a multi-scale(molecular-nanometer-micrometer) investigation of the interphase and itsrelationship to polymer matrix composite (PMC) performance. The firstobjective of the research is to monitor the chemistry of the interphaseregion in situ, and in real-time during the polymer curing cycle. Thesecond objective is to measure the size and the mechanical properties of theinterphases that result as a function of silane coupling agent surfacetreatments. The third objective is the measurement of the micromechanicalperformance of a model PMC system. Several tasks are involved to meet the research objectives. Thefirst task will involve in situ reaction monitoring of a model polymer usinga novel Fourier transform infrared fiber optic sensor system which allowsdirect monitoring of interphase chemistry. Experiments will be performedusing polymer/curing agent mixtures on unmodified glass fibers, and polymercuring followed as a function of time at elevated temperature. Next, silanecoupling agent surface treatments will be performed on the glass fibers andthe organofunctional reactivity determined simultaneously with curingagent/polymer reactivity. The second task in the proposed research will be the nano-mechanicalproperty characterization after surface treatment and polymer curing.Atomic force microscopy and nanoindentation will be used to characterize theinterphase region. These results will be correlated with the in situinfrared data from the first task, in particular, the role oforganofunctional reactivity and polymer curing on the resultant interphaseproperties. The third task will involve measurement of the micromechanicalbehavior of the model PMC through the use of the microbond test method.Results obtained during this portion of the research will be correlated withthe first two tasks mentioned above.