Establishing Structural Changes of Aging PV Module Backsheets

During a photovoltaic (PV) module backsheet's aging process, DuraMAT focuses on establishing possible polymer structural changes that intervene in its morphology and chemical composition.

Several key parameters determine the properties of a polymer: chemical composition, molecular weight distribution, topology, isomerism, and morphology. Each of these parameters influences the polymer mechanical properties. Morphology defines the overall form of the polymer structure, including crystallinity, branching, molecular weight, crosslinking, and other physical properties. 

We focus mostly on understanding the crystallinity of the backsheet polymers. In particular, we're researching the changes in the amorphous and crystalline properties in comparison between pristine and aged samples. Ultimately, we seek to understand what changes, structurally and chemically, intervene in the module backsheet, so that the material properties drastically decay to rupture.

We measure four types of backsheet materials in pristine and aged conditions. It also provides soft matter, small and wide-angle X-ray scattering (SAXS/WAXS), which is capable of measuring and visualizing the morphological configuration and changes in polymers.