PX521 · reinforced grade
PX521-MF
Properties of the MF condition, compared with the other PX521 grades.
Choose for cast worktops, sinks and sanitary ware where thickness, stiffness, thermal stability and repairable matte surfaces matter more than clarity.
What is PX521-MF?
PX521-MF is PX521 in the MF grade — choose for cast worktops, sinks and sanitary ware where thickness, stiffness, thermal stability and repairable matte surfaces matter more than clarity. PX521-MF has a tensile strength of 40 MPa (5.8 ksi), weaker than 56% of polymer grades. Elongation at break is 0.7% and the elastic modulus is 8.5 GPa (1.23 Msi). PX521-MF has a density of 1.7 g/cm³ (0.0614 lb/in³), heavier than 94% of polymer grades. Its glass-transition temperature is 110°C (230 °F). UV Resistant is the default condition FabDigit quotes; MF is available on request or by drawing note.
Advantages
- Conducts heat well — 0.6 W/m·K (0.347 BTU/hr·ft·°F), better than 99% of polymer grades
- Stiff — 8.5 GPa (1.23 Msi), better than 90% of polymer grades
- Polishes to a fine finish — 80/100, better than 89% of polymer grades
- Good UV / weathering resistance — 85/100, better than 88% of polymer grades
Limitations
- Limited ductility — 0.7%, worse than 99% of polymer grades
- Heavy — 1.7 g/cm³ (0.0614 lb/in³), worse than 94% of polymer grades
- Low fracture toughness — 1.1 MPa·√m (1 ksi·√in), worse than 80% of polymer grades
- Needs corrosion protection — 70/100, worse than 80% of polymer grades
PX521-MF properties
Typical room-temperature values for PX521-MF — 18 properties are specific to this condition; the rest are grade-level values shared by every PX521 grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical6
PX521-MF has a density of 1.7 g/cm³ (0.0614 lb/in³), heavier than 94% of polymer grades. Its glass-transition temperature is 110°C (230 °F).
Mechanical15
PX521-MF has a tensile strength of 40 MPa (5.8 ksi), weaker than 56% of polymer grades. Elongation at break is 0.7% and the elastic modulus is 8.5 GPa (1.23 Msi).
Thermal11
PX521-MF is rated for continuous service to 95°C (203 °F). It conducts heat at 0.6 W/m·K (0.347 BTU/hr·ft·°F), better than 99% of polymer grades. Thermal expansion is 38 µm/m·K (21.1 µin/in·°F).
Electrical7
PX521-MF is an electrical insulator with a dielectric strength of 30 kV/mm (762 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (70/100), worse than 80% of polymer grades. UV resistance is excellent.
Sustainability4
Producing a kilogram of PX521-MF takes about 100 MJ of energy and emits 6.5 kg of CO₂ — less than 61% of polymer grades. Typical recycled content is 5%.
Manufacturability4
PX521-MF's machinability is very good (70/100, better than 73% of polymer grades); weldability poor (30/100); formability good (60/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other PX521 grades and fills
PX521 is also supplied in 6 other conditions. The full side-by-side table is on the PX521 overview.
- UV ResistantDefaultDefault choice for outdoor signage, glazing, lenses and displays needing long-term non-yellowing clarity.72 MPa tensile
- OPTPick for lenses, light guides and precision optics where haze and internal stress must be minimal.74 MPa tensile
- EMBPick for thick-section embedments (specimens, trophies, decorative inclusions) where cure exotherm and shrink cracking must be controlled.62 MPa tensile
- IMUse where edge chipping, drilling near edges or vandal/impact loads would crack standard cast acrylic.52 MPa tensile
- MFChoose for cast worktops, sinks and sanitary ware where thickness, stiffness, thermal stability and repairable matte surfaces matter more than clarity.40 MPa tensile
- FRSpecify for transport interiors, building panels and enclosures needing low flame spread/smoke from an acrylic casting.34 MPa tensile
Working with PX521-MF
Is PX521 easy to machine?
Machines cleanly with sharp carbide, high speed/low feed, 0° to slightly positive rake and air or mist cooling; anneal 2–4 h at 75–80 °C before and after heavy cuts to avoid crazing, and avoid coolant with alcohols.
Can PX521 be welded?
Not thermally welded in practice — join with MMA/solvent cement (acrylic dichloromethane or two-part methacrylate adhesive) for optically clear, near-parent-strength bonds; UV-cure acrylic adhesives for clear glazing joints.
Can PX521 be formed, bent or molded?
Cast between silicone/glass tooling at 40–70 °C with post-cure to 90–110 °C; thick sections need slow ramped cure to control exotherm and shrink voids, and finished plate thermoforms at 150–170 °C.
What surface finishes work on PX521?
Sand progressively then flame-, diamond- or buff-polish to optical clarity; accepts hard-coat/anti-scratch and anti-reflective coatings, screen printing and acrylic-compatible paints — mask edges from solvent-based cleaners.
PX521 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 |
|---|---|---|
| crosslinker (glycol dimethacrylate type)raises solvent and heat resistance of the casting | 0 – 2 | 0.5 |
| peroxide initiator (e.g. dibenzoyl/peroxcure package; sometimes with amine/redox accelerator | 0.05 – 0.6 | 0.25 |
| UV absorber / HALS stabilizerbenzotriazole-type; source of the UV-Resistant designation | 0.1 – 1 | 0.4 |
| release / flow / defoaming additives | 0 – 0.5 | 0.15 |
| alumina trihydrate (ATH) filleronly in MF / FR solid-surface variants (typ. 55–62 wt %) | 0 – 65 | 0 |
| methyl methacrylate (MMA) monomer + PMMAbulk-polymerized in mould; residual monomer typically <1 % after full cure | ≥ 92 (balance) | — |
PX521-MF — frequently asked
What is PX521-MF used for?
PX521-MF is typically used for vacuum casting prototypes, clear industrial prototypes, lenses, light pipes and lighting covers, display and instrument windows, outdoor signage and glazing panels and flow-visualisation and fluid-path models. In short: UV-stable outdoor resin.
What is the tensile strength of PX521-MF?
PX521-MF has a typical tensile strength of 40 MPa (5.8 ksi) — weaker than 56% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is PX521-MF easy to machine?
Yes — machinability is rated very good (70/100, better than 73% of polymer grades). Machines cleanly with sharp carbide, high speed/low feed, 0° to slightly positive rake and air or mist cooling; anneal 2–4 h at 75–80 °C before and after heavy cuts to avoid crazing, and avoid coolant with alcohols.
Can PX521-MF be welded?
Not readily — weldability is rated poor (30/100). Not thermally welded in practice — join with MMA/solvent cement (acrylic dichloromethane or two-part methacrylate adhesive) for optically clear, near-parent-strength bonds; UV-cure acrylic adhesives for clear glazing joints.
What surface finishes work on PX521-MF?
Sand progressively then flame-, diamond- or buff-polish to optical clarity; accepts hard-coat/anti-scratch and anti-reflective coatings, screen printing and acrylic-compatible paints — mask edges from solvent-based cleaners.
Can PX521-MF be formed, bent or molded?
Cast between silicone/glass tooling at 40–70 °C with post-cure to 90–110 °C; thick sections need slow ramped cure to control exotherm and shrink voids, and finished plate thermoforms at 150–170 °C.
What is the maximum service temperature of PX521-MF?
PX521-MF is rated for continuous use to about 95°C (203 °F), and briefly to 95°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in PX521-MF?
Yes — PX521-MF is available for injection molding and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Engineered Materials Handbook Vol. 2: Engineering Plastics (PMMA section) — ASM International (1988)
- CAMPUS plastics database — PMMA cast/moulding grades typical values — CWFG / CAMPUS consortium (2024)
- ISO 7823-1 Cast poly(methyl methacrylate) sheets — requirements and test methods — ISO (2003)
- ASTM D4802 Poly(methyl methacrylate) Acrylic Plastic Sheet — ASTM International (2021)
- Cast acrylic sheet & casting-resin technical data (clear, impact-modified, mineral-filled solid surface) — Acrylic sheet/resin producers (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.