Looking for High-Performance Plastic Components?
Acetal homopolymer is an engineering thermoplastic polymer that provides good strength and stiffness. DuPont Delrin® is a popular acetal homopolymer brand name and the most commonly used acetal homopolymer. It is easily machined with conventional metal working equipment into custom components having very close tolerances. Both sheet and rod are available in many thicknesses and diameters. Rod stock comes ground to diameter to accommodate through spindle turning. Standard colors are black and (opaque) milk white, while custom colors are available as custom runs. Also, homopolymer acetals have a low-density centerline/core porosity, especially in thicker sheet sections.
Acetal homopolymer absorbs minimal amounts of moisture, is slightly stronger, but has less chemical resistance than copolymer acetals. Therefore it is often used in applications in industrial equipment, such as conveyor and machinery components.
Although it has many benefits as an unfilled material, Acetal homopolymer can also be filled with solid lubricants and or glass fibers to enhance its structural, bearing and wear properties. Materials such as glass, PTFE, Graphite and oil are all available in standard sizes.
Delrin® is a registered trademark of DuPont.
| Specification | Test | Value | Units |
| Specific Gravity, 73°F | D792 | 1.41 | - |
| Tensile Strength @ Yield, 73°F | D638 | 11,000 | psi |
| Tensile Modulus of Elasticity, 73°F | D638 | 450,000 | psi |
| Tensile Elongation (at break), 73°F | D638 | 30 | % |
| Flexural Strength, 73°F | D790 | 13,000 | psi |
| Flexural Modulus of Elasticity | D790 | 450,000 | psi |
| Shear Strength, 73°F | D732 | 9,000 | psi |
| Compressive Strength - Ultimate | 1,000 | psi | |
| Compressive Strength at 2% Deformation | D695 | 1,000 | psi |
| Compressive Strength at 10% Deformation | D695 | 16,000 | psi |
| Deformation Under Load | 2 | % | |
| Compressive Modulus of Elasticity, 73°F | D695 | 450,000 | |
| Compressive Strength ⊥ to Laminate (Modulus) | 1,000 | psi | |
| Compressive Strength ⊥ to Laminate (Yield) | 1,000 | psi | |
| Compressive Strength ⊥ to Laminate (Ultimate) | 1,000 | psi | |
| Hardness, Durometer (Shore "D" scale) | D2240 | D89 | |
| Hardness, Rockwell (Scale as noted) | D785 | M89 (R122) | Rockwell M |
| Izod Impact, Notched @ 73°F | D256 Type A | 1.0 | ft.lbs/in. of notch |
| Coefficient of Friction (Dry vs Steel) Static | PTM 55007 | 0.30 | |
| Coefficient of Friction (Dry vs Steel) Dynamic | PTM 55007 | 0.25 | |
| Maximum Static Bearing Load (P) | PTM 55007 | 1,000 | psi |
| Maximum Unlubricated No Load Bearing Velocity (V) | PTM 55007 | 15 | ft/minute |
| Maximum Limiting PV (Unlubricated) | PTM 55007 | 2,700 | psi x ft/min. |
| Wear Factor "K" x 10-10 | PTM 55010 | 200 | Cubic in.-min/ft.lbs.hr |
| Sand Wheel Wear/Abrasion Test | 60 | UHMW=100 | |
| Minimum Mating Surface Hardness | 20 | Rockwell (Brinnell) | |
| Coefficient of Linear Thermal Expansion | E-831 (TMA) | 4.7 | in/in/°F x 10-5 |
| Coefficient of Thermal Expansion // to Laminates | E-831 (TMA) | 4.7 | in/in/°F x 10-5 |
| Coefficient of Thermal Expansion I to Laminates | E-831 (TMA) | 4.7 | in/in/°F x 10-5 |
| Softening Point | 250 | °F | |
| Heat Deflection Temperature 264 psi | D648 | 250 | °F |
| Embrittlement Temperature | °F Min. | ||
| Continuous Service Temperature in Air | 180 | °F Max. | |
| Short Term Service Temperature | 212 | °F Max. | |
| Tg-Glass Transition (Amorphous) | D3418 | °F | |
| Melting Point (Crystalline) Peak | D3418 | 347 | °F |
| Thermal Conductivity | F433 | 2.5 | BTU-in/(hr/ft2°F) |
| Dielectric Strength Short Term | D149 | 450 | Volts/mil |
| Surface Resistivity | D257 | >1013 | ohm/cm |
| Volume Resistivity | D257 | ohm/cm | |
| Dielectric Constant, 106 Hz | D150 | 3.7 | |
| Dissipation Factor, 106 Hz | D150 | 0.005 | |
| Flammability @ 3.1mm(1/8 in.) UL94 | UL94 | HB | |
| Arc Resistance | seconds | ||
| Water Absorption, Immersion 24 Hours | D570 (2) | 0.2 | % |
| Water Absorption, Immersion Saturation | D570 (2) | 0.9 | % |
| Machinability Rating | 1 | 1=easy, 10=difficult | |
| Rod Diameter Availability (Off the Shelf) | .125 | 60 | inches |
| Sheet Thickness Availability (Off the Shelf) | .030 | 3.0 | inches |