ABSTRACT
A defining characteristic of polymer molecules is their high molecular weight. In general, infrared spectra do not respond to changes in the molecular weight of a sample. This chapter discusses the spectra of plastics that are commonly collected by municipalities and recycled in quantities of millions of pounds per year. Polyethylene is an economically important polymer. Billions of pounds of it are made per year. Polypropylene is another common polymer found in everything from food bowls to disposable diapers. Polystyrene is another economically important polymer and, is one of the six commonly recycled packaging plastics. By definition, polyesters contain an ester group as part of the polymer backbone. Polyamides comprise a diverse but important family of polymeric materials. The members of the acrylate family of polymers are made from acrylic acid and its derivatives. Polymethyl methacrylate is an important member of the acrylate family.
