About 1952, research chemists at DuPont synthesized a version of POM, and in 1956 the company filed for patent protection of the homopolymer. DuPont credits scientist R. N. MacDonald as the inventor of high-molecular-weight POM. Patents by MacDonald and coworkers describe the preparation of high-molecular-weight hemiacetal-terminated (~O−CH2OH) POM, but these lack sufficient thermal stability to be commercially viable. The inventor of a heat-stable (and therefore useful) POM homopolymer was Stephen Dal Nogare, who discovered that reacting the hemiacetal ends with acetic anhydride converts the readily depolymerizable hemiacetal into a thermally stable, melt-processable plastic.
Acetal Copolymer vs Delrin® acetal homopolymer
DuPont offers materials with unique properties that withstand extreme temperatures and other demanding environments. DuPont offers high quality, productivity and sustainable solutions for the printing and package printing industry. The Dupont Delrin is a Homopolymer Acetal, or POM-H material. The common Acetal material is a Copolymer Acetal resin, or it is called POM-C.
Brand Names: Delrin®, Tecaform, Ultraform, Celcon
Polyoxymethylene (POM), also known as acetal, Polyacetal and polyformaldehyde, is an engineering thermoplastic used in precision parts requiring high stiffness, low friction, and excellent dimensional stability. As with many other synthetic polymers, it is produced by different chemical firms with slightly different formulas and sold variously by such names as: Delrin, Celcon, Ramtal, Duracon, Kepital and Hostaform.
Delrin® – The high-performance acetal resin that global customers trust
In 1960, DuPont completed construction of a plant to produce its own version of acetal resin, named Delrin, at Parkersburg, West Virginia. Also in 1960, Celanese completed its own research. Shortly thereafter, in a limited partnership with the Frankfurt firm Hoechst AG, a factory was built in Kelsterbach, Hessen; from there, Celcon was produced starting in 1962, with Hostaform joining it a year later. Both remain in production under the name Celanese and are sold as parts of a product group now called Hostaform/Celcon POM.
Differences Between Acetal Products
The Co-Polymer Acetal is produced by a wide variety of large plastic manufacturers, BASF is probably one of the largest and most well known. Some main resin names are: BASF Ultraform H4320, Kepital F10-02, or Hostaform M25. While Delrin is a wonderful material, in larger cross sections or larger diameters, the Dupont Delrin brand Homo-Polymer can exhibit center line porosity. This can sometimes be seen with the naked eye, and is a darker white in a normally milky white natural colored material. This center line porosity can cause problems in some applications. This porosity can cause leakage of fluid if under pressure, or ‘soft centers’ of Dupont™ Delrin® Rod and Dupont Delrin Sheet. Delrin and Acetal Copolymer are electrical materials but are also excellent choices for use in food beverage applications. The categories plastics are used in are vast and varied, and product services with Acetal materials and rod acetal sizes seem to fit many application requirements. Dupont Delrin Acetal Rod materials machine extremely well when compared to other plastics polymers or polymer resins. Most machine shops prefer the Delrin brand materials over most other engineering thermoplastics as this may improve performance over many metal parts.dupont™ delrin®
Delrin® offers major benefits over acetal copolymer
The key properties that Delrin have are: higher tensile strength, increased Izod impact, higher deflection temperatures and it is slightly harder. These cost effective plastic materials are found to be resins engineering companies prefer. The coefficient of thermal expansion is a bit higher, and needs to be considered when designing a new part. Delrin brand material also comes in several resin variations, including: Delrin 150 and Delrin 507, contact us for details. Video of: Machining Delrin (Acetal) vs UHMW – Lathing Many of our clients prefer the Delrin brand rod and sheet for small machined parts. This is due to the increase in a few key properties, and of course brand recognition. Both resins meet the standard ASTM-D-6778, and the cancelled specs, L-P-395 and ASTM-D-4181. Dupont Delrin® Sheets and Delrin Rods have many of the same physical characteristics of industrial metals such as brass, aluminum, zinc, and stainless steel materials. Delrin is a homopolymer acetal (POM). Some of Dupont Delrin’s comparable properties include stiffness, dimensional stability, impact resistance, and structural strength. Delrin® 150 is standard general purpose, unfilled acetal. This grade has the best impact toughness of all unfilled Delrin products. Delrin® 150 SA was discontinued in 2003 & replaced by Delrin 150. Delrin Rods are Produced in Standard 10 Foot Lengths, in a wide range of diameters.