What is an example of a natural plastic?

Amber is considered a natural plastic because it is a fossilized resin that originates from trees and possesses characteristics similar to synthetic plastics. Over millions of years, the organic material in tree resin hardens, leading to a substance that can be shaped and polished. Unlike synthetic plastics like polyethylene, polyvinyl chloride (PVC), and cellulose acetate—which are created through chemical processes or polymerization of synthetic materials—amber's natural formation processes give it unique properties and a historical significance as a natural polymer.

While cellulose acetate is derived from natural cellulose, it undergoes significant modification and processing in its manufacture, categorizing it more closely with synthetic plastics. The other materials listed are fully synthetic and produced from petroleum-based resources, separating them from the classification of natural plastics. Amber, therefore, serves as the quintessential example of a natural plastic, demonstrating the distinction between materials sourced from nature and those manufactured through chemical industry processes.