Polyethylene (PE) is a ubiquitous material in our daily life appearing as milk bottles, toys and diapers. A lesser-known but increasingly important use of PE is as underground gas and water pipes, because of its ease of installation and lack of corrosion. Blends of PE with two different molecular architectures are the prevailing materials for water mains with a projected service life up to 100 years. Due to a lack of chemical contrast, the microscopic structure of these blends has been studied primarily by indirect bulk-averaging methods, such as calorimetry and neutron scattering. For the first time ever, we demonstrate that a newly developed broadband coherent anti-Stokes Raman Scattering (CARS) microscopy can resolve the spatial distribution of species with different molecular architectures as well as orientation of their semi-crystalline structures. This work demonstrates the unique capability of CARS microscopy to address challenges existing in PE blends for water mains such as thermal joining and long-term service life prediction.
Citation: ACS Macro Letters
Pub Type: Journals
polyethylene, spherulite, CARS, Raman, imaging