Raman spectroscopic characterization of laminated glass and transparent sheet plastics to amplify a history of early aviation 'glass'

摘要

A novel, non-invasive study of goggles, flight helmets, airplane windows, and canopies in Smithsonian collections is the first known large-scale technical survey of historic aviation plastics and leverages the world's largest air and space collection as evidence of the materials and technologies used to create transparent plastic objects in the early-20th century. Transparent windows in these artifacts were analyzed with Fourier transform and portable dispersive Raman spectrometers to identify polymers and plasticizers present. The study demonstrates the potential of Raman spectroscopy to objectively and non-destructively measure historic plastic compositions, including formulations that have become obsolete. Data was interpreted in combination with archival research of historical documents to identify window materials including glass, laminated safety glass, and sheets of plasticized cellulose nitrate, plasticized cellulose acetate, and poly(methyl methacrylate). Results are contextualized into a coherent history of the role transparent plastics played in enclosing airplane cockpits. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.