Published December 2002
Acetal resins, also known as polyacetals or polyoxymethylenes (POM) with characteristic building blocks -CH2O- (oxymethylene oxide), is a family of crystalline engineering plastics, known for their natural lubricity, dimensional stability, stiffness, fatigue endurance, creep and corrosion resistance, combined with regrind stability and ease of molding. They consist mainly of homopolymers and copolymers.
Homopolymers are produced by polymerizing formaldehyde and are produced by companies such as DuPont in the United States and Western Europe, and by Asahi Kasei in Japan. Copolymers, on the other hand, are produced by copolymerizing trioxane with a small amount of a co-monomer by companies such as Ticona (owned by Hoechst Celanese) and Ultraform (owned by BASF) in the United States and Western Europe; and by Asahi Kasei, Mitsubishi Gas Chemical and Polyplastics (Daicel and Hoechst Celanese joint venture) in Japan.
Growth of acetal resins has been driven by strong consumption in United States, Western Europe and Asia, as well as new grades in new uses in automobiles, electronics, medical devices, and sanitary sectors. Since the issue of PEP Report "Acetal Resins" (June 1971), main technology development efforts of the producers have been concentrated particularly on heat stabilization and tailor-made specialty grades/blends.
This report presents a comprehensive assessment of the status of the acetal resins industry, particularly homopolymers and copolymers. It provides a review of current patents and recent business/technology developments, and evaluates two major commercial processes. This report also presents updates of the techno-economics in the production of homopolymers from formaldehyde and copolymers from trioxane. Results of our economic analysis indicate that the homopolymerization process is somewhat more expensive in total fixed capital than the copolymerization process for producing acetal resins of comparable properties. Although the raw material costs for the homopolymer is lower, the higher cost of utilities and capital related fixed costs nonetheless result in product value that is about 15% higher than the copolymer.
Overall, this report encompasses the latest technology developments and process economics, and it provides a basis for insight into acetal resin's technology trends.