Acetal Homopolymer (Delrin®) (Celcon®) (Acetron®)

Acetal (Homopolymer) is an engineering thermoplastic polymer that provides good strength and stiffness. Commonly known as Delrin® or Acetron®, it is slightly stronger than its copolymer counterpart and 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 Teflon®, Graphite and oil are all available in standard sizes.

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/
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
Characteristics / Attributes Rigid / Stiff / Strong / Excellent Machinability