Synthetic Polymers: Polyesters, Polyethers, Polysulfones, and Other Polymers

Abstract

Commercial use of polyester resins dates from the early twentieth century, when alkyd resins were first used in surface coatings. The polyesters are found today as fibers, films, laminating resins, molding resins, and engineering plastics. Many high‐molecular‐weight polyethers are used as engineering plastics, as are the polysulfides and the polysulfones. The available basic properties are provided. Many of the high‐molecular‐weight polyethers are used as engineering plastics, as are the polysulfides and the polysulfones. Important properties of these compounds and production data for the general categories are provided. Processing techniques vary widely and are also discussed. Industrial hygiene concerns with these polymers depend on the type of resin in use and processing techniques. As an example, the use of styrene in polyester resins that are fabricated into glass‐reinforced plastics can provide the greatest intensity of exposure to styrene in workplace situations. Toxic vapors can also be released by solvent systems at elevated temperatures and during fabrication of engineering resins. Sulfur‐containing engineering resins typically have a high resistance to thermal deterioration but may yield toxic hydrogen sulfide or sulfur dioxide if heated to decomposition temperatures. No specific standards are available that pertain to ordinary industrial use of the finished polymeric products. However, there are occupational exposure limits for the monomers and additives used to synthesize or process these polymers. In addition, there are occupational exposure limits for dust and particles that may be applicable.