Polymer chemistry is a sub-discipline of chemistry that focuses on the synthesis, structure, and properties of polymers—large molecules, or macromolecules, composed of repeating structural units known as monomers. This field investigates how the chemical composition and architecture of these long chains, including their molecular weight and arrangement, dictate the physical and chemical characteristics of a material, such as its strength, elasticity, and thermal stability. As a highly applied and interdisciplinary science, it provides the foundation for creating a vast array of synthetic materials, including plastics, rubbers, and fibers, while also being essential for understanding natural macromolecules like proteins and DNA.