Boedeker Plastics, Inc. Logo -- boedeker plastics supply shiner
     texas tx usa boedeker plastics material supply shiner texas usa plastics
     distributor plastics sales plastics supply plastics machine shop

Acetal (PolyOxy-Methylene) Specifications

904 West 6th Street, Shiner, Texas 77984 USA
Phone: 1-361-594-2941     Fax: 1-361-594-2349     E-Mail:


BPI Home Page | Applications | Materials Guide | Contact Us!

blue line

click to resize photo Acetal is the common name for a family of thermoplastics with the chemical name "PolyOxy-Methylene". Acetal is available in a general purpose copolymer grade, a homopolymer version (Delrin ®), and several filled Delrin ® grades. Acetal provides high strength and stiffness, enhanced dimensional stability, and is easy to machine. As a semi-crystalline material, acetal is characterized by a low coefficient of friction and good wear properties.

( see also Pomalux Static-Control Acetal and Semitron ESd 225 Static-Dissipative Acetal )

• High strength, stiffness, dimensional stability • Very low moisture absorption • Good wear and abrasion resistance • Wide range chemical resistance (including many solvents)

The copolymer grade offers excellent performance at a slightly lower cost than Delrin ® homopolymer. Some acetal copolymer may exhibit center line porosity, but porosity-free material is available. Certain grades are FDA, USDA, NSF, Canada AG and 3-A Dairy compliant. Low stress levels and high strength assure flatness and dimensional stability up to a maximum continuous service temperature of 180°F (80°C). Acetal copolymers are available in a wide variety of colors (see above photo), including  BLACK ,  GREY ,  WHITE ,  BLUE ,  GREEN ,  YELLOW ,  ORANGE ,  RUST ,  RED  &  BROWN .

DELRIN ® (unfilled)
Delrin ® acetal homopolymer offers slightly higher mechanical properties than acetal copolymer, but may contain a low density center (also known as "center line porosity") especially in large cross-sections. The homopolymer also gives slightly less chemical resistance than copolymer acetal. For example, Delrin ® is ideal for small diameter, thin-walled bushings that benefit from the additional strength and rigidity of homopolymer acetal. Delrin ® is available in  BLACK  &  NATURAL  colors.

NOTE: Brand name Delrin sheet, rod and tube may be manufactured from any one of several DuPont resins, depending upon the size, cross-sectional thickness, and production equipment being used to produce the molded shapes.

In 2002, DuPont Company discontinued production of Delrin ® II 550SA resin ... this has been replaced by Delrin ® 511P. For more details use these links to view our .PDF files:
Letter of ExplanationDelrin 511P resin datasheetDelrin II 550SA resin datasheet

In 2004, DuPont Company discontinued production of Delrin ® II 150SA and Delrin ® II 150E (Natural) resins ... these grades have been replaced by Delrin ® 150. For more details use these links to view our .PDF files:
Letter of ExplanationDelrin 150 resin datasheetDelrin II 150SA resin datasheet

DELRIN ® AF (PTFE-filled)
This material is manufactured from Delrin ® homopolymer resin which has been uniformly filled with a dispersion of PTFE fibers. Delrin ® AF is a unique thermoplastic material for use in moving parts in which low friction and long wear life are important. It retains 90% of the mechanical strength of unfilled acetal homopolymer, while offering very low friction and almost no "slip-stick" behavior. Delrin ® AF is  BROWN  in color.
In 2006, DuPont Company changed the composition of Delrin ® AF resins ... the PTFE fiber manufacturing process has been modified to substantially reduce PFOA emissions in cooperation with EPA guidelines. The old and new materials have identical properties, except that the new polymer is a much darker brown color. For comparison, the old material was similar to a Milk Chocolate Brown and the new material looks more like a Dark Chocolate Brown. For more details use these links to view our .PDF files:
Ensinger Letter of ExplanationDuPont Letter of Explanation

blue line


ASTM or UL test Property Acetal
Delrin ®
Delrin ® AF
D792 Density (lb/in³)
D570 Water Absorption, 24 hrs (%) 0.2 0.2 0.2
D638 Tensile Strength (psi) 9,500 11,000 8,000
D638 Tensile Modulus (psi) 400,000 450,000 435,000
D638 Tensile Elongation at Break (%) 30 30 15
D790 Flexural Strength (psi) 12,000 13,000 12,000
D790 Flexural Modulus (psi) 400,000 450,000 435,000
D695 Compressive Strength (psi) 15,000 16,000 16,000
D695 Compressive Modulus (psi) 400,000 450,000 350,000
D785 Hardness, Rockwell M88 / R120 M89 / R122 M85 / R115
D256 IZOD Impact Notched (ft-lb/in) 1.0 1.0 0.7
D696 Coefficient of Linear Thermal Expansion
(x 10-5 in./in./°F)
5.40 4.70 5.00
D648 Heat Deflection Temp (°F / °C)
at 264 psi

220 / 104

250 / 121

244 / 118
D3418 Melting Point Temp (°F / °C) 335 / 168 347 / 175 347 / 175
- Max Operating Temp (°F / °C) 180 / 82 180 / 82 180 / 82
C177 Thermal Conductivity
(x 10-4 cal/cm-sec-°C)



UL94 Flammability Rating HB HB HB
D149 Dielectric Strength (V/mil) short time, 1/8" thick 420 450 400
D150 Dielectric Constant at 1 MHz 3.8 3.7 3.1
D150 Dissipation Factor at 1 MHz 0.005 0.005 0.010
D257 Volume Resistivity (ohm-cm) at 50% RH 1015 1015 3.0 x 1016

NOTE: The information contained herein are typical values intended for reference and comparison purposes only. They should NOT be used as a basis for design specifications or quality control. Contact us for manufacturers' complete material property datasheets.
All values at 73°F (23°C) unless otherwise noted.
DELRIN is a registered trademark of DuPont

blue line

Boedeker Plastics, Inc.
904 West 6th Street, Shiner, Texas 77984 USA
USA TOLLFREE : 1-800-444-3485
Phone: 1-361-594-2941     Fax: 1-361-594-2349     E-Mail:

©     Copyright Boedeker Plastics, Inc.