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PMMA-Optical OF

Grade

OF = optical fibre / light-pipe core grade

Pick for POF cores and long light pipes where attenuation per metre, not mechanics, is the limiting property.

Standard cost $$

Values for the OF condition

Other PMMA-Optical grades and fills

PMMA-Optical is listed in 7 conditions; see the grade overview at PMMA-Optical.

Compare all 7 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
Impact-modified optical grade
Pick when parts must survive handling/drop loads and a small loss of clarity and stiffness is acceptable.—503065 HRM
Flame-retardant transparent grade
Pick for lighting diffusers and display housings that must meet a UL94 V rating; expect some haze and lower clarity.6062388 Shore D
Light-guide plate grade
Pick for thin backlight light-guide plates where long optical path length and thin-wall filling dominate.66683.588 Shore D
UV-transmitting optical grade
Pick for UV curing windows, tanning/analytical optics and sensors needing transmission down to ~300 nm (no UV absorber added).68704.589 Shore D
OFThis page
Optical fibre / light-pipe core grade
Pick for POF cores and long light pipes where attenuation per metre, not mechanics, is the limiting property.7274490 Shore D
Heat-resistant optical grade
Pick for LED/lamp optics or lenses cured near 110–130 °C where standard PMMA distorts.73753.590 Shore D
As cast
Pick for large optical windows, laser-cut/engraved parts and thick blanks needing best surface flatness and machinability.7476592 Shore D

What is PMMA-Optical OF?

PMMA-Optical OF is PMMA-Optical in the OF grade — pick for POF cores and long light pipes where attenuation per metre, not mechanics, is the limiting property. PMMA-Optical OF has a yield strength of 72 MPa (10.4 ksi) and a tensile strength of 74 MPa (10.7 ksi) — stronger than 82% of polymer grades. Elongation at break is 4% and the elastic modulus is 3.3 GPa (0.479 Msi). PMMA-Optical OF has a density of 1.19 g/cm³ (0.043 lb/in³), heavier than 53% of polymer grades. Its glass-transition temperature is 105°C (221 °F).

Advantages

  • Polishes to a fine finish — 96/100, better than 99% of polymer grades
  • Good UV / weathering resistance — 88/100, better than 90% of polymer grades
  • High strength — 72 MPa (10.4 ksi), better than 82% of polymer grades
  • Stiff — 3.3 GPa (0.479 Msi), better than 80% of polymer grades

Limitations

  • Low fracture toughness — 1.1 MPa·√m (1 ksi·√in), worse than 82% of polymer grades
  • Limited ductility — 4%, worse than 78% of polymer grades

PMMA-Optical OF properties

Typical room-temperature values for PMMA-Optical OF; 27 are specific to this condition. Other listed values are PMMA-Optical reference data and may not represent this condition. Bars are the position among polymer grades.

Physical6

PMMA-Optical OF has a density of 1.19 g/cm³ (0.043 lb/in³), heavier than 53% of polymer grades. Its glass-transition temperature is 105°C (221 °F).

Density1.19 g/cm³0.04 lb/in³
Glass Transition (Tg)105°C221 °F
Water Absorption (24 h)0.25%
Water Absorption (Saturation)2%
Refractive Index1.492
Light Transmission93%

Mechanical16

PMMA-Optical OF has a yield strength of 72 MPa (10.4 ksi) and a tensile strength of 74 MPa (10.7 ksi) — stronger than 82% of polymer grades. Elongation at break is 4% and the elastic modulus is 3.3 GPa (0.479 Msi).

Elastic (Young's) Modulus3.3 GPa0.48 Msi
Shear Modulus1.2 GPa0.17 Msi
Bulk Modulus5 GPa0.73 Msi
Poisson's Ratio0.37
Tensile Strength (Ultimate)74 MPa10.7 ksi
Yield Strength (0.2% offset)72 MPa10.4 ksi
Elongation at Break4%
Compressive Strength110 MPa16 ksi
Compressive Modulus3 GPa0.44 Msi
Flexural Strength110 MPa16 ksi
Flexural Modulus3.3 GPa0.48 Msi
Shear Strength60 MPa8.7 ksi
Fracture Toughness (K_IC)1.1 MPa·√m1 ksi·√in
Izod Impact, Notched17 J/m0.32 ft·lbf/in
Hardness, Shore D90 Shore D
Hardness, Rockwell M96 HRM

Thermal11

PMMA-Optical OF is rated for continuous service to 75°C (167 °F). It conducts heat at 0.19 W/m·K (0.11 BTU/hr·ft·°F), worse than 68% of polymer grades. Thermal expansion is 70 µm/m·K (38.9 µin/in·°F).

Thermal Conductivity0.19 W/m·K0.11 BTU/hr·ft·°F
Specific Heat Capacity1,470 J/kg·K0.35 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)70 µm/m·K38.9 µin/in·°F
Max Service Temperature (continuous)75°C167 °F
Min Service Temperature-40°C-40 °F
Heat Deflection Temp. @ 0.45 MPa98°C208 °F
Heat Deflection Temp. @ 1.8 MPa92°C198 °F
Vicat Softening Point (B50)108°C226 °F
Flammability (UL 94)HB (3.0 mm); burns readily, no halogen-free V-rating without FR additives
Limiting Oxygen Index18%
Max Service Temperature (short-term)95°C203 °F

Electrical7

PMMA-Optical OF is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹³ Ω·m.

Electrical Resistivity1×10¹³ Ω·m3.94×10²⁰ µΩ·in
Dielectric Strength25 kV/mm635 V/mil
Dielectric Constant (1 MHz)2.8
Dissipation Factor (1 MHz)0.02
Volume Resistivity1×10¹⁵ Ω·cm
Surface Resistivity1×10¹⁶ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is very good (72/100), worse than 70% of polymer grades. UV resistance is excellent.

Corrosion ResistanceVery good72/100
UV / Weathering ResistanceExcellent88/100
Chemical Resistance SummaryGood against water, dilute acids/alkalis, aliphatic hydrocarbons, mineral oils and detergents; attacked or dissolved by ketones (acetone, MEK), esters, chlorinated solvents, aromatics, and prone to environmental stress cracking with alcohols/IPA and adhesive vapours under load.

Sustainability4

Producing a kilogram of PMMA-Optical OF takes about 105 MJ of energy and emits 6.2 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 0%.

Embodied Energy (primary production)105 MJ/kg45,142 BTU/lb
Embodied Carbon (primary production)6.2 kg CO₂/kg
Embodied Water280 L/kg33.6 gal/lb
Typical Recycled Content0%

Manufacturability8

PMMA-Optical OF's machinability is good (68/100, better than 71% of polymer grades); weldability fair (40/100); formability poor (25/100).

MachinabilityGood68/100
WeldabilityFair40/100
Formability (cold)Poor25/100
PolishabilityExcellent96/100
Mold Shrinkage0.5%
Melt Flow Rate2.5 g/10 min
Processing Melt Temperature (typ.)245°C473 °F
Mold Temperature (typ.)75°C167 °F

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with PMMA-Optical OF

Is PMMA-Optical easy to machine?

Machines and diamond-turns to optical finish with sharp positive-rake tools, high speed and low feed; use coolant/air blast and avoid dwell to prevent crazing, and anneal (~80 °C) before and after cutting to relieve stress.

Can PMMA-Optical be welded?

No fusion welding — join by solvent (dichloromethane/MMA cement), UV-cure acrylic adhesive, ultrasonic or laser welding; avoid solvent vapour on stressed parts to prevent crazing.

Can PMMA-Optical be formed, bent or molded?

Dry 4–6 h at 80–90 °C to <0.05 % moisture, inject at 225–265 °C melt with 60–95 °C mould, slow fill and high holding pressure for low birefringence; thermoform sheet at 150–180 °C.

What surface finishes work on PMMA-Optical?

Flame or diamond polishing gives near-optical edges; hard-coat (siloxane/UV-cure) for scratch and chemical resistance, vacuum AR/metallic coatings adhere well after plasma treatment.

PMMA-Optical 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.

ElementSpec limit (wt %)Nominal
methyl acrylate / ethyl acrylate comonomadded for thermal stability and flow in injection grades0 – 63
chain transfer agent / residual monomer mercaptan CTA, mould release, antioxidant; UV absorber only in UV-cut grades0 – 10.3
methyl methacrylate (MMA)polymerized MMA backbone; optical grades use high-purity, low-metal monomer≥ 92 (balance)—

PMMA-Optical OF — frequently asked

What is PMMA-Optical OF used for?

PMMA-Optical OF is typically used for light guide plates (LGP), optical lenses, plastic optical fiber and camera/display components. In short: lowest-birefringence PMMA; diamond-turnable optical grade; costliest acrylic grade.

What is the yield strength of PMMA-Optical OF?

PMMA-Optical OF has a typical yield strength of 72 MPa (10.4 ksi) and a tensile strength of 74 MPa (10.7 ksi) — stronger than 82% of polymer grades. Strength varies by condition: see the 7 listed tempers.

Is PMMA-Optical OF easy to machine?

Reasonably — machinability is rated good (68/100, better than 71% of polymer grades). Machines and diamond-turns to optical finish with sharp positive-rake tools, high speed and low feed; use coolant/air blast and avoid dwell to prevent crazing, and anneal (~80 °C) before and after cutting to relieve stress.

Can PMMA-Optical OF be welded?

With care — weldability is rated fair (40/100). No fusion welding — join by solvent (dichloromethane/MMA cement), UV-cure acrylic adhesive, ultrasonic or laser welding; avoid solvent vapour on stressed parts to prevent crazing.

What surface finishes work on PMMA-Optical OF?

Flame or diamond polishing gives near-optical edges; hard-coat (siloxane/UV-cure) for scratch and chemical resistance, vacuum AR/metallic coatings adhere well after plasma treatment.

Can PMMA-Optical OF be formed, bent or molded?

Dry 4–6 h at 80–90 °C to <0.05 % moisture, inject at 225–265 °C melt with 60–95 °C mould, slow fill and high holding pressure for low birefringence; thermoform sheet at 150–180 °C.

What is the maximum service temperature of PMMA-Optical OF?

PMMA-Optical OF is rated for continuous use to about 75°C (167 °F), and briefly to 95°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. ISO 8257-1/-2 Plastics — Poly(methyl methacrylate) moulding and extrusion materials — ISO (2021)
  2. JIS K 6717 Poly(methyl methacrylate) moulding materials — JSA (2019)
  3. Engineered Materials Handbook Vol.2: Engineering Plastics — ASM International (1988)
  4. Acrypet optical / light-guide grade data sheets — Mitsubishi Chemical (2023)
  5. Plexiglas / Altuglas acrylic resin and sheet data — Röhm / Trinseo (2023)
  6. CAMPUS plastics database — PMMA property profiles — CWFG (2024)

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.