PMMA-HI
ASTM D788 · JIS K6717 · GB GB/T 7134 Type 2 · ISO 8257-2 PMMA-HI
PMMA-HI is a rubber-toughened acrylic — elastomeric impact modifiers dispersed in a PMMA matrix — covered by ASTM D788, JIS K6717 and GB/T 7134 Type 2.
Reference datasheet — PMMA-HI 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.
PMMA-HI grades and fills
PMMA-HI is supplied in 4 conditions, soft to hard.
Compare all 4 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Flame-retardant impact grade | For electrical enclosures, luminaire diffusers and rail/transport parts needing a flammability rating. | 43 | 45 | 15 | 86 Shore D |
High-flow impact grade | Choose for thin-wall light guides and long flow paths where fill pressure matters more than maximum toughness. | 45 | 47 | 22 | 85 Shore D |
Pigmented / opaque impact grade | Coloured or white-opaque compounds for cosmetic housings, sanitary and appliance parts where gloss and scratch resistance beat ABS. | 46 | 48 | 26 | 86 Shore D |
Heat-resistant impact grade | Use where parts see 90–110 °C service (headlamp inner lenses, near-LED optics) and standard HI would distort. | 51 | 53 | 22 | 88 Shore D |
Supply forms, finishes and certifications
Ways PMMA-HI is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
EXT | Extrusion / sheet grade | Supply form |
MED | Medical / food-contact certified impact grade | Certification |
UV | UV-stabilised / weatherable impact grade | Grade option |
NATDefault | Unfilled / natural transparent impact-modified injection grade | Standard supply |
What is PMMA-HI?
PMMA-HI is a rubber-toughened acrylic — elastomeric impact modifiers dispersed in a PMMA matrix — covered by ASTM D788, JIS K6717 and GB/T 7134 Type 2. At 50 MPa tensile strength and about 30 % elongation it tolerates handling and impact far better than general-purpose acrylic, and is stocked as sheet, extruded profile and moulding pellets in HF, EXT, UV, HH, FR, MED and OPQ variants. The trade-offs are lower clarity, surface hardness and stiffness than GP PMMA, and no fusion welding. Polycarbonate is the nearest alternative when impact energy is higher. PMMA-HI has a density of 1.16 g/cm³ (0.0419 lb/in³), lighter than 55% of polymer grades. Its glass-transition temperature is 102°C (216 °F). PMMA-HI has a yield strength of 48 MPa (6.96 ksi) and a tensile strength of 50 MPa (7.25 ksi) — weaker than 53% of polymer grades. Elongation at break is 30% and the elastic modulus is 2.2 GPa (0.319 Msi).
What is PMMA-HI used for?
- Skylights
- Aircraft canopies
- Machine guards
- Impact-resistant glazing
Advantages
- Polishes to a fine finish — 85/100, better than 92% of polymer grades
- Good UV / weathering resistance — 82/100, better than 87% of polymer grades
- Easy to machine — 78/100, better than 81% of polymer grades
- Forms and bends easily — 82/100, better than 77% of polymer grades
Limitations
- Limited service temperature — 72°C (162 °F), worse than 75% of polymer grades
PMMA-HI properties
Typical room-temperature values; bars are the position among polymer grades.
Physical6
PMMA-HI has a density of 1.16 g/cm³ (0.0419 lb/in³), lighter than 55% of polymer grades. Its glass-transition temperature is 102°C (216 °F).
Mechanical17
PMMA-HI has a yield strength of 48 MPa (6.96 ksi) and a tensile strength of 50 MPa (7.25 ksi) — weaker than 53% of polymer grades. Elongation at break is 30% and the elastic modulus is 2.2 GPa (0.319 Msi).
Thermal11
PMMA-HI is rated for continuous service to 72°C (162 °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 75 µm/m·K (41.7 µin/in·°F).
Electrical7
PMMA-HI is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (75/100), worse than 66% of polymer grades. UV resistance is very good.
Sustainability4
Producing a kilogram of PMMA-HI takes about 103 MJ of energy and emits 5.6 kg of CO₂ — less than 54% of polymer grades. Typical recycled content is 2%.
Manufacturability8
PMMA-HI's machinability is very good (78/100, better than 81% of polymer grades); weldability good (62/100); formability very good (82/100).
Common Calculations5
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. PMMA-HI is highlighted; hover a dot for its name, or open the interactive family chart.
Working with PMMA-HI
Is PMMA-HI easy to machine?
Machines cleanly with sharp positive-rake carbide, high speed and low feed; less crazing/chipping than GP acrylic but still use coolant/air blast and avoid dwelling to prevent local softening.
Can PMMA-HI be welded?
No true fusion welding in practice — join by solvent cement (MMA/dichloromethane blends), acrylic structural adhesive, ultrasonic or hot-plate welding; anneal before solvent bonding to avoid stress crazing.
Can PMMA-HI be formed, bent or molded?
Dry 4 h at 80–90 °C before moulding; melt 210–260 °C, mould 50–90 °C, moderate injection speed and generous gates; thermoform sheet at 150–175 °C with shrinkage allowance ~0.4–0.7 %.
PMMA-HI 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 |
|---|---|---|
| methyl methacrylate (MMA) unitsPMMA matrix | 70 – 92 | 82 |
| acrylate comonomer (methyl/ethyl acrylatthermal stability / flow modifier | 1 – 6 | 3 |
| core-shell acrylic elastomer (butyl acryimpact modifier; MBS/butadiene types used in some non-weatherable grades | 8 – 25 | 15 |
| UV absorber / stabiliser / lubricant add | 0.1 – 1.5 | 0.5 |
What surface finishes work on PMMA-HI?
Flame or diamond polishing restores gloss (haze slightly higher than GP PMMA); can be hard-coated for abrasion/UV, vacuum metallised or pad/screen printed with acrylic-compatible inks; anneal 80 °C to relieve stress before coating.
Equivalent designations
Standards and trade names that resolve to PMMA-HI in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- D788
- ISO
- 8257-2 PMMA-HI
- GB (China)
- GB/T 7134 Type 2
- JIS
- K6717
How much does PMMA-HI cost?
PMMA-HI 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.
PMMA-HI — frequently asked
What is PMMA-HI used for?
PMMA-HI is typically used for skylights, aircraft canopies, machine guards and impact-resistant glazing. In short: highest-impact acrylic grade; about 30 % elongation; less crazing when machined.
What is the yield strength of PMMA-HI?
PMMA-HI has a typical yield strength of 48 MPa (6.96 ksi) and a tensile strength of 50 MPa (7.25 ksi) — weaker than 53% of polymer grades. Strength varies by condition: see the 4 listed tempers.
Is PMMA-HI easy to machine?
Yes — machinability is rated very good (78/100, better than 81% of polymer grades). Machines cleanly with sharp positive-rake carbide, high speed and low feed; less crazing/chipping than GP acrylic but still use coolant/air blast and avoid dwelling to prevent local softening.
Can PMMA-HI be welded?
Yes — weldability is rated good (62/100). No true fusion welding in practice — join by solvent cement (MMA/dichloromethane blends), acrylic structural adhesive, ultrasonic or hot-plate welding; anneal before solvent bonding to avoid stress crazing.
What surface finishes work on PMMA-HI?
Flame or diamond polishing restores gloss (haze slightly higher than GP PMMA); can be hard-coated for abrasion/UV, vacuum metallised or pad/screen printed with acrylic-compatible inks; anneal 80 °C to relieve stress before coating.
Can PMMA-HI be formed, bent or molded?
Dry 4 h at 80–90 °C before moulding; melt 210–260 °C, mould 50–90 °C, moderate injection speed and generous gates; thermoform sheet at 150–175 °C with shrinkage allowance ~0.4–0.7 %.
What is the maximum service temperature of PMMA-HI?
PMMA-HI is rated for continuous use to about 72°C (162 °F), and briefly to 90°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does PMMA-HI cost?
PMMA-HI 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
- ISO 8257-2 Plastics — PMMA moulding and extrusion materials — Preparation of test specimens and determination of properties — ISO (2021)
- ASTM D788 Standard Classification System for Poly(Methyl Methacrylate) Molding and Extrusion Compounds — ASTM (2018)
- Impact-modified acrylic moulding compound datasheets (Plexiglas zk / Altuglas HFI / Sumipex HT / Acrypet IR series) — Röhm, Trinseo/Altuglas, Sumitomo, Mitsubishi Chemical (2023)
- CAMPUS plastics database — PMMA impact-modified grade property sets (ISO 10350-1) — CWFG/CAMPUS (2024)
- ASM Engineered Materials Handbook, Vol. 2: Engineering Plastics — ASM International (1988)
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.