Acetal Copolymer vs Delrin® Homopolymer Properties
Comparing Acetal Copolymer to Dupont Delrin
Acetal Copolymer vs Dupont Delrin® Homopolymer: Properties and Benefits of Each
Industrial Plastic Supply, Inc. has been supplying a vast inventory of plastics to a wide customer base since 1975. Today, we put the spotlight on two products that are incredibly similar, but have key differences that result in each performing optimally in certain applications: the Acetal Copolymer and the Delrin® Homopolymer.
Both of these acetal plastic materials are incredibly similar, with similar beneficial properties. They are both compliant with FDA, ITAR, and RoHS standards. Both are very stiff plastics with excellent dimensional stability in average environments. They are self-lubricating, easy to cut with standard tools, and abrasion and wear resistant. The major differences between them however are a result of their differing structures.
What Is Polyoxymethylene
Polyoxymethylene (also known as POM for short) is an important and commonly used engineering plastic material. There are two distinct types of POM; the first is Homopolymer Acetal plastic and is commonly called TJC LP Delrin® (formerly Dupont Delrin®). The other is Copolymer Acetal and is referred to by the trade names Celcon®, Sustarin® C, Tecaform®, Ultraform®, Kepital® acetal plastic and many others. Both versions of POM are very popular thermoplastic materials. They both are commonly used for parts that need to be stiff, dimensionally stable and have low surface friction.
TJC LP Delrin® (formerly Dupont Delrin®) Homopolymer
The homopolymer possesses much more regularity in its structure, with a repeated, crystalline pattern throughout the plastic. As a result of its strong, crystalline makeup, the TJC LP Delrin® Homopolymer has superior physical properties, such as better fatigue and creep resistance, and bearing properties. Also, it has better short-term heat resistance compared to the acetal copolymer, with a much higher melting point.
However, this homopolymer does experience minor and inherent center-line porosity. This is basically a band area of tiny porous holes along the center of a rod or sheet. Depending on the severity of the porosity, these holes could weaken a finished part or cause other problems with its performance.
Acetal Copolymer
We’ve found that our customers tend to gravitate towards the acetal copolymer when they require a wider processing window, lower costs, and better long-term resistance to heat and alkaline environments. The acetal copolymer is not as crystalline in its structure, which causes it to not only have a generally lower melting point, but when incorporated with other materials, also increases the tolerance for high melting temperatures.
The less crystalline structure of the copolymer means that this plastic isn’t quite as strong. However, its mixed molecular structure has several benefits. The acetal copolymer has improved resistance to oxidation, improved chemical resistance, and much better long-term resistance to heat. That difference in chemical resistance is much more pronounced with exposure to hot water, especially chlorinated water. The acetal copolymer (polyacetal delrin) survives much longer than the homopolymer in these conditions.
Final Thoughts
Both the Acetal Copolymer and the TJC LP Delrin® Homopolymer have their benefits. Depending on your application and requirements, you can choose the best acetal plastic for your needs. In need of a local plastic distributors or plastic suppliers of plastics and plastic materials, or plastic distributors near me (plastic companies near me)? Check out the best ‘plastic supplier near me’, and 50 years experience at Industrial Plastic Supply today!