UF
ASTM D705
UF is a urea-formaldehyde amino thermoset supplied as a cellulose- or wood-flour-filled molding powder under the ASTM D705 family, with mineral-filled, melamine-modified (MUF), high-impact, adhesive (E1/E0) and foam variants on file.
Reference datasheet — UF is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the CELL condition
UF grades and fills
UF is supplied in 7 conditions, soft to hard. CELL is the default FabDigit quotes; the values on this page are for it.
Compare all 7 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
UF foam | Choose the in-situ foamed ultra-low-density product (0.012 g/cm³, 0.035 W/m·K) for filling wall cavities; strength, moisture resistance and shrinkage behaviour are all poor. | 0.02 | 1.5 | ||
Liquid UF adhesive resin | Use the liquid adhesive resin at roughly 55–65% solids for particleboard and plywood bonding where GB/T 39600 E1 formaldehyde emission limits are sufficient. | 40 | 0.5 | 100 HRM | |
Mineral-filled | Use the mineral-filled grade for electrical parts needing higher heat resistance to 90 °C, lower water absorption and steadier dielectric behaviour; machinability drops to a score of 30. | 48 | 118 HRM | ||
Wood-flour / cellulose-pulp filled | Choose the wood-flour or paper-pulp filled grade to cut cost on dark, non-cosmetic parts such as junction boxes and bases, accepting 52 MPa strength and 70 °C service. | 52 | 110 HRM | ||
Impact-modified / cellulose-fabric reinforced | Pick the long cellulose-fibre or rag-fabric reinforced impact grade for electrical parts exposed to mechanical shock; toughness rises markedly while service stays at 75 °C. | 60 | 1 | 105 HRM | |
CELLDefault Cellulose-filled | Pick the α-cellulose filled molding powder (ASTM D705 Type I) for bright-coloured, glossy switch plates, lampholders and bottle caps; service temperature is limited to 75 °C. | 65 | 0.8 | 115 HRM | |
Melamine-modified UF | Choose the melamine-modified formulation for boiling-water resistance, 95 °C service and higher surface hardness in tableware and water-resistant adhesives, at intermediate cost. | 70 | 120 HRM |
Supply forms, finishes and certifications
Ways UF is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
ADH-E0 | Liquid UF adhesive resin | Certification |
What is UF?
UF is a urea-formaldehyde amino thermoset supplied as a cellulose- or wood-flour-filled molding powder under the ASTM D705 family, with mineral-filled, melamine-modified (MUF), high-impact, adhesive (E1/E0) and foam variants on file. It is chosen for low cost, a hard glossy molded surface and good dielectric properties in compression- and transfer-molded wiring devices, and as a wood-panel adhesive resin. Density is 1.5 g/cm³ and tensile strength 65 MPa, but the compound is brittle, absorbs moisture, is limited to 75 °C service and yellows with age; melamine-formaldehyde or phenolic (PF) is the usual step up. UF has a density of 1.5 g/cm³ (0.0542 lb/in³), heavier than 88% of polymer grades. Its glass-transition temperature is 130°C (266 °F). UF has a tensile strength of 65 MPa (9.43 ksi), stronger than 73% of polymer grades. Elongation at break is 0.8% and the elastic modulus is 9 GPa (1.31 Msi).
What is UF used for?
- Electrical switches and sockets
- Wood adhesives
- Small appliance housings
Advantages
- Stiff — 9 GPa (1.31 Msi), better than 93% of polymer grades
- Conducts heat well — 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades
- Low embodied carbon — 3.2 kg CO₂/kg, better than 81% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- Limited ductility — 0.8%, worse than 98% of polymer grades
- Difficult to weld — 0/100, worse than 98% of polymer grades
- Limited formability — 5/100, worse than 95% of polymer grades
- Needs corrosion protection — 55/100, worse than 94% of polymer grades
- Heavy — 1.5 g/cm³ (0.0542 lb/in³), worse than 88% of polymer grades
UF properties
Typical room-temperature values for UF-CELL; bars are the position among polymer grades.
Physical5
UF has a density of 1.5 g/cm³ (0.0542 lb/in³), heavier than 88% of polymer grades. Its glass-transition temperature is 130°C (266 °F).
Mechanical12
UF has a tensile strength of 65 MPa (9.43 ksi), stronger than 73% of polymer grades. Elongation at break is 0.8% and the elastic modulus is 9 GPa (1.31 Msi).
Thermal10
UF is rated for continuous service to 75°C (167 °F). It conducts heat at 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades. Thermal expansion is 30 µm/m·K (16.7 µin/in·°F).
Electrical7
UF is an electrical insulator with a dielectric strength of 14 kV/mm (355.6 V/mil) and a resistivity of 1×10¹⁰ Ω·m.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 94% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of UF takes about 80 MJ of energy and emits 3.2 kg of CO₂ — less than 85% of polymer grades. Typical recycled content is 0%.
Manufacturability6
UF's machinability is fair (40/100, worse than 82% of polymer grades); weldability not recommended (0/100); formability not recommended (5/100).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. UF is highlighted; hover a dot for its name, or open the interactive family chart.
Working with UF
Is UF easy to machine?
Drills, turns and taps, but the material is brittle and the fillers abrade tooling — use carbide with sharp positive-rake edges, high speed and light feed, and back up the part to avoid edge chipping. Run dust extraction; no coolant is needed.
Can UF be welded?
Not weldable; the network is cross-linked. Join with epoxy or cyanoacrylate adhesive, molded-in inserts or self-tapping screws.
Can UF be formed, bent or molded?
Compression and transfer molding are the standard routes: mold 140–170 °C, 15–35 MPa, cure 20–60 s/mm. Preheat the charge and vent the tool to release the condensation water from the polycondensation reaction; store molding powder cool and sealed, since overage powder pre-cures and loses flow.
UF chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| ureacondenses with formaldehyde to form urea-formaldehyde matrix | 25 – 40 | 32 |
| formaldehydeF/U molar ratio 1.0-1.6; lower ratio lowers formaldehyde emission | 20 – 32 | 26 |
| alpha-cellulose filler (α )main filler in general-purpose molding powder | 25 – 40 | 33 |
| latent acid catalyst ( / ) | 0.3 – 1.5 | 0.8 |
| lubricant ( / ) | 0.3 – 1.5 | 0.8 |
| pigments / opacifier | 0.5 – 5 | 2 |
| moisture & volatiles | 1 – 4 | 2.5 |
What surface finishes work on UF?
Parts release with a high-gloss molded skin, so finishing is normally limited to deflashing and polishing. The surface cannot be plated or anodized; screen and pad printing adhere well, and long outdoor exposure causes yellowing.
Equivalent designations
Standards and trade names that resolve to UF in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- D705
How much does UF cost?
UF is a standard-cost polymer ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
UF — frequently asked
What is UF used for?
UF is typically used for electrical switches and sockets, wood adhesives and small appliance housings. In short: lowest-cost amino thermoset; hard glossy molded finish; 75 °C service ceiling.
What is the tensile strength of UF?
UF has a typical tensile strength of 65 MPa (9.43 ksi) — stronger than 73% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is UF easy to machine?
Not especially — machinability is rated fair (40/100, worse than 82% of polymer grades). Drills, turns and taps, but the material is brittle and the fillers abrade tooling — use carbide with sharp positive-rake edges, high speed and light feed, and back up the part to avoid edge chipping. Run dust extraction; no coolant is needed.
Can UF be welded?
Not readily — weldability is rated not recommended (0/100). Not weldable; the network is cross-linked. Join with epoxy or cyanoacrylate adhesive, molded-in inserts or self-tapping screws.
What surface finishes work on UF?
Parts release with a high-gloss molded skin, so finishing is normally limited to deflashing and polishing. The surface cannot be plated or anodized; screen and pad printing adhere well, and long outdoor exposure causes yellowing.
Can UF be formed, bent or molded?
Compression and transfer molding are the standard routes: mold 140–170 °C, 15–35 MPa, cure 20–60 s/mm. Preheat the charge and vent the tool to release the condensation water from the polycondensation reaction; store molding powder cool and sealed, since overage powder pre-cures and loses flow.
What is the maximum service temperature of UF?
UF is rated for continuous use to about 75°C (167 °F), and briefly to 100°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does UF cost?
UF is a standard-cost polymer ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM D705 — Standard Specification for Urea Formaldehyde Molding Compounds — ASTM International (2018)
- Engineered Materials Handbook, Vol. 2: Engineering Plastics (Amino Resins) — ASM International (1988)
- Modern Plastics Handbook — Thermosets — McGraw-Hill (2000)
- Amino (UF/MF) molding compound technical data — Hexion / Dynea / (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.