Actually, rayon is made from the cellulose derived from wood and is a "natural" fiber, and was developed in the late 1800's and put to commercial use in the early 1900's. Read below:
Rayon is produced from naturally occurring polymers and therefore it is not a synthetic fiber, but a manufactured regenerated cellulosic fiber.
Georges Audemars developed the first "artificial silk" about 1855, but his method was impractical for commercial use. Hilaire de Charbonnet, Comte de Chardonnay, patented "Chardonnay silk" in 1884, but it was so flammable it had no safe use. Finally, in 1894, Charles Frederick Cross, Edward John Bevan, and Clayton Beadle patented the first safe and practical artificial silk, which they named "viscose." Avtex Fibers Incorporated began selling their formulation in 1910 in the United States. The name "rayon" was adopted in 1924, with "viscose" being used for the viscous organic liquid used to make both rayon and cellophane. In Europe, though, the fabric itself became known as "viscose," which has been ruled an acceptable alternative term for rayon by the Federal Trade Commission.
Rayon was only produced as a filament fiber until the 1930s when it was discovered that broken waste rayon could be used in staple fiber. The physical properties of rayon were unchanged until the development of high-tenacity rayon in the 1940s. Further research and development led to the creation of high-wet-modulus rayon (HWM rayon) in the 1950s
So while it is possible that rayon was used by Imperial Germany, I am trying to find evidence that it actually was used.
There is a seller that is marketing these so-called "late war" bayonet troddeln (knots) that have rayon in the tassels. This seller claims that they are original. I am trying to prove that they are indeed fakes, and alert the Imperial German collecting community to their existence.
Any help would be greatly appreciated!