“Manufacturers had begun developing synthetic fibers as early as the 1930s, but much of the production shifted to military purposes during the war. Wartime research accelerated the development of synthetic fibers, which were used for making parachutes, tents, and ropes, and improved the fibers’ quality while driving down costs. When peacetime resumed, manufacturers found that bridal gowns were a uniquely good fit for the burgeoning supply of the materials: the fabrics were far less expensive and easier to deal with than satin and silk, making the dresses more widely available.”
Victoria Finkle details in “Why Do Brides Wear White?” article.