is a chemistry subdiscipline that deals with the structures, chemical synthesis and properties of polymers, primarily synthetic polymers
such as plastics and elastomers. Polymer chemistry is related to the broader field of polymer science, which also encompasses polymer physics and polymer engineering
. The chemist Hermann Staudinger first proposed that polymers consisted of long chains of atoms held together by covalent bonds, which he called macromolecules. His work expanded the chemical understanding of polymers and was followed by an expansion of the field of polymer chemistry
during which such polymeric materials as neoprene, nylon and polyester were invented. Polymers
are high molecular mass compounds formed by polymerization
of monomers. The simple reactive molecule from which the repeating structural units of a polymer are derived is called a monomer. A polymer is chemically described by its degree of polymerisation, molar mass distribution, tacticity, copolymer distribution, the degree of branching, by its end-groups, crosslinks, crystallinity and thermal properties such as its glass transition temperature and melting temperature. Polymers in solution have special characteristics with respect to solubility, viscosity and gelation.