Product/Service

Acetals

Source: DSM Engineering Plastic Products
For General Purpose Parts in Wet Environments
For General Purpose Parts in Wet Environments

Product Profile:

  • Low moisture absorption
  • High strength stiffness
  • Easy to machine
  • centerline porosity in Acetron GP
  • Many formulation options: Copolymer, Homopolymer, Teflon filled, and Internally lubricated/enhanced wear grade

Acetal provides high strength and stiffness coupled with enhanced dimensional stability and ease of machining. As a semi-crystalline material, acetal is also characterized by a low coefficient of friction and good wear properties-especially in wet environments.

Because acetal absorbs minimal amounts of moisture, its physical properties remain constant in a variety of environments. Low moisture absorption gives excellent dimensional stability for close-tolerance machined parts. In high moisture or submerged applications, acetal bearings outperform nylon 4 to 1. Acetal is ideally suited for close tolerance mechanical parts and electrical insulators which require strength and stiffness. It also offers resistance to a wide range of chemicals including many solvents.

DSM offers both homopolymer and copolymer grades of acetal including three enhanced bearing grade materials. Acetron GP acetal is porosity-free and offered as our standard general purpose grade. For slightly higher mechanical properties, we offer a broad size range of the homopolymer acetal (Delrin) products. For improved frictional properties PTFE-enhanced Delrin AF products are available.

Acetron GP Acetal
Acetron DGP is DSM's general purpose copolymer acetal and is the only porosity-free acetal product available today. Investments in process technology by DSM now provide the performance and machinability of acetal without center core porosity. Our in-line photometric quality procedure assumes every plate and rod is porosity-free as measured by DSM's dye penetrant test making it the preferred acetal for food contact and medical applications. Acetron GP natural is FDA, USDA, NSF, Canada AG and 3A-Dairy compliant.

Derlin Acetal
Derlin, a homopolymer acetal, is also manufactured and stocked in rod and plate. It offers slightly higher mechanical properties than Acetron GP Acetal, but may contain a low-density center, especially in larger cross-sections. Copolymer acetal also offers better chemical resistance than homopolymer acetal.

Delrin is ideal for small diameter, thin-walled bushings that benefit from the additional strength and rigidity of homopolymer acetal.

Delrin AF Blend
Delrin AF Blend is a unique thermoplastic material for use in moving parts in which low friction and long wear life are important. It is a combination of PTFE fibers uniformly dispersed in Delrin acetal resin. This combination offers better wear characteristics than unfilled Delrin.

Delrin AF Blend, supplied as a 2:1 blend of Delrin AF100 and Delrin 150 resins, has excellent sliding/friction properties. Bearings made of Delrin AF Blend can operate at higher speeds while exhibiting reduced wear. These bearings are also essentially free of slip-stick behavior because the static and dynamic coefficient of friction are closer than with most plastics.

Delrin AF Blend contains 90% of the strength that is inherent in unmodified Delrin acetal. Some properties are changed due to the addition of the softer PTFE fiber. The natural color of Delrin AF Blend is dark brown.

Delrin* AF 100
Unblended Delrin AF, offers a slightly higher limiting PV and lower coefficient of friction due to additional PTFE content. This added PTFE typically decreases the wear capability and impact strength. Delrin AF 100 is available on a custom basis.

DSM Engineering Plastic Products, 2120 Fairmont Ave., PO Box 14235, Reading, PA 19612-4235. Tel: 610-320-6600; Fax: 610-320-6868.