Technical Material Comparison
| Material | Typical Forming Temp | Shore / Rockwell Hardness | Continuous Service Temp | Key Strength | Main Limitation |
|---|---|---|---|---|---|
| Acrylic / PMMA | 290°F–350°F | Rockwell M90–M100 | ~160°F–180°F | Excellent clarity, polishability, weather resistance | Brittle compared to PC/PETG |
| Polycarbonate / PC | 350°F–400°F | Rockwell M70–M80 | ~240°F | Very high impact resistance | Scratches easier; must be dried before forming |
| PETG | 250°F–320°F | Rockwell R105–R115 | ~140°F–160°F | Clear, tough, easy to form | Lower heat resistance than PC/acrylic |
| HDPE | 260°F–300°F | Shore D60–D70 | ~180°F | Chemical resistance, moisture resistance, toughness | High thermal expansion; poor adhesive bonding |
| UHMW | Usually machined, not commonly thermoformed | Shore D60–D70 | ~180°F | Low friction, abrasion resistance, impact resistance | Poor dimensional stability vs acetal |
| Acetal / Delrin | Usually machined, not commonly thermoformed | Rockwell M80–M90 | ~180°F–220°F | Precision, stiffness, low friction | Not ideal for strong acids/oxidizers |
| Nylon | Usually machined; thermoforming uncommon | Rockwell R100–R120 | ~180°F–220°F | Strength, wear resistance, toughness | Absorbs moisture; dimensional movement |
| ABS | 275°F–350°F | Rockwell R95–R115 | ~160°F–180°F | Impact resistance, formability, housings/covers | Poor UV resistance unless modified |
| HIPS | 250°F–325°F | Rockwell R70–R95 | ~150°F–170°F | Low cost, easy forming, printability | Lower strength and durability |
| Expanded PVC | Usually cut/routed, not precision thermoformed | Shore D50–D60 | ~140°F–160°F | Lightweight, printable, easy to machine | Not for high-load mechanical parts |
| PVC Type I | 250°F–325°F | Shore D75–D85 | ~140°F–160°F | Chemical resistance, rigidity | Heat limitations; avoid laser cutting |
Note: The values above are typical ranges for general material selection only. Actual properties vary by manufacturer, grade, thickness, color, additives, and processing method. For engineered applications, final material selection should be based on the specific grade’s data sheet and the part’s operating environment.
Acrylic / PMMA
Overview
Acrylic is a rigid, clear thermoplastic used when optical clarity, polished appearance, and weather resistance matter. It is common in displays, signage, panels, covers, and fabricated acrylic parts.
Common name: Plexiglas
Typical technical properties
- Forming temperature: approximately 290°F–350°F
- Hardness: Rockwell M90–M100
- Continuous service temperature: approximately 160°F–180°F
- Light transmission: commonly around 92% for clear sheet
- Impact resistance: higher than glass, but much lower than polycarbonate
- Water absorption: low
- Chemical resistance: good with many mild cleaners; poor with some solvents
- Outdoor performance: good UV/weather resistance
Processing notes
- Laser cuts well, especially cast acrylic
- CNC routes well with proper tooling
- Can be heat bent, drape formed, polished, bonded, and fabricated
- Cast acrylic usually machines and polishes better than extruded acrylic
- Extruded acrylic is often more economical but can behave differently when machined, polished, or formed
Best uses
Displays, signs, acrylic panels, risers, covers, windows, decorative parts, and premium visual components.
Polycarbonate / PC
Overview
Polycarbonate is a clear engineering plastic used when impact resistance matters. It is commonly used for machine guards, safety shields, equipment windows, protective covers, and transportation or marine panels.
Common Name: Lexan
Typical technical properties
- Forming temperature: approximately 350°F–400°F
- Hardness: Rockwell M70–M80
- Continuous service temperature: approximately 240°F
- Impact resistance: extremely high compared with acrylic
- Water absorption: low
- Chemical resistance: sensitive to some cleaners, solvents, and chemicals
- Outdoor performance: use UV-stabilized or coated grades for long-term exposure
- Drying before forming: usually required to avoid bubbles
Processing notes
- CNC routes and drills well with proper tooling
- Can be cold bent in thinner gauges
- Can be thermoformed, but drying is critical
- Not ideal for CO₂ laser cutting because edges can burn, char, or discolor
- Scratches more easily than acrylic unless hard-coated
Best uses
Machine guards, impact-resistant windows, safety shields, equipment covers, marine panels, and protective glazing.
PETG
Overview
PETG is a clear plastic used when a part needs clarity, toughness, and easy forming. It sits between acrylic and polycarbonate in many applications.
Typical technical properties
- Forming temperature: approximately 250°F–320°F
- Hardness: Rockwell R105–R115
- Continuous service temperature: approximately 140°F–160°F
- Impact resistance: better than acrylic, lower than polycarbonate
- Chemical resistance: good with many mild chemicals
- Water absorption: low
- Outdoor performance: depends on grade; not always ideal for long-term UV exposure
Processing notes
- Thermoforms well
- Easier to fabricate and bend than acrylic
- CNC routes well
- Softer surface than acrylic
- Not usually selected for polished-edge display work
Best uses
Clear trays, covers, displays, formed guards, protective panels, and medical/lab equipment covers.
HDPE
Overview
HDPE is a durable polyethylene material used for industrial, outdoor, marine, food-processing, and utility parts. It is tough, moisture resistant, and chemically resistant.
Typical technical properties
- Forming temperature: approximately 260°F–300°F
- Hardness: Shore D60–D70
- Continuous service temperature: approximately 180°F
- Coefficient of friction: low compared with many rigid plastics
- Moisture absorption: very low
- Chemical resistance: very good
- Impact resistance: good
- Thermal expansion: high compared with acrylic, acetal, or polycarbonate
Processing notes
- CNC routes well
- Does not glue easily
- Usually requires mechanical fastening or welding
- Can move with temperature changes
- Not used when optical clarity or polished appearance is required
Best uses
Marine panels, outdoor parts, cutting surfaces, guides, utility panels, food-processing support parts, and durable industrial components.
UHMW
Overview
UHMW is a very low-friction, high-wear polyethylene used for sliding, guiding, conveying, and impact applications. It is common in packaging machinery, conveyor systems, food plants, and industrial equipment.
Typical technical properties
- Forming temperature: not typically thermoformed; usually machined
- Hardness: Shore D60–D70
- Continuous service temperature: approximately 180°F
- Coefficient of friction: very low
- Abrasion resistance: excellent
- Impact resistance: excellent
- Moisture absorption: very low
- Chemical resistance: very good
- Thermal expansion: high
Processing notes
- CNC machines well, but is soft and can move
- Poor adhesive bonding
- Not ideal for tight-tolerance precision components
- Usually mechanically fastened
- Excellent for replacing metal in sliding/wear applications
Best uses
Wear strips, chain guides, conveyor guides, chute liners, bottle handling parts, packaging machine parts, and low-friction replacement components.
Acetal / Delrin
Overview
Acetal is a precision engineering plastic used for machined mechanical components. Delrin is a common acetal brand name.
Typical technical properties
- Forming temperature: not commonly thermoformed; usually machined
- Hardness: Rockwell M80–M90
- Continuous service temperature: approximately 180°F–220°F
- Moisture absorption: low
- Coefficient of friction: low
- Wear resistance: good
- Dimensional stability: very good compared with HDPE/UHMW
- Machinability: excellent
Processing notes
- Excellent for CNC machining
- Holds tighter tolerances than HDPE or UHMW
- Good for pockets, holes, profiles, and precision features
- Not generally bonded with standard adhesives
- Better for precision parts than UHMW when stiffness matters
Best uses
Bushings, rollers, gears, spacers, machine components, fixtures, guides, and precision replacement parts.
Nylon
Overview
Nylon is a strong engineering plastic used for wear parts, rollers, bushings, structural components, and industrial machine parts.
Typical technical properties
- Forming temperature: not commonly thermoformed; usually machined
- Hardness: Rockwell R100–R120, depending on grade
- Continuous service temperature: approximately 180°F–220°F
- Strength: high for a plastic
- Wear resistance: good
- Moisture absorption: moderate to high
- Impact resistance: good
- Dimensional stability: affected by humidity and moisture
Processing notes
- CNC machines well
- Good for load-bearing and wear applications
- Can absorb moisture and change dimensions
- Acetal may be better where tight tolerance and low moisture absorption matter
Best uses
Rollers, bushings, wear pads, spacers, machine parts, and mechanical components.
ABS
Overview
ABS is a tough, formable plastic used for vacuum formed parts, covers, housings, trays, panels, and enclosures.
Typical technical properties
- Forming temperature: approximately 275°F–350°F
- Hardness: Rockwell R95–R115
- Continuous service temperature: approximately 160°F–180°F
- Impact resistance: good
- Rigidity: good
- Chemical resistance: moderate
- UV resistance: poor unless UV-stabilized or capped
- Formability: very good
Processing notes
- Vacuum forms well
- CNC trims well after forming
- Available in smooth, textured, colored, and capped grades
- Good for practical covers and housings
- Not clear
Best uses
Vacuum formed housings, covers, trays, enclosures, panels, and equipment components.
HIPS
Overview
HIPS is a low-cost, formable plastic often used for displays, trays, packaging-related components, and lightweight formed parts.
Typical technical properties
- Forming temperature: approximately 250°F–325°F
- Hardness: Rockwell R70–R95
- Continuous service temperature: approximately 150°F–170°F
- Impact resistance: moderate
- Rigidity: moderate
- Formability: excellent
- Printability: good
- UV resistance: limited
Processing notes
- Forms easily
- Cost-effective for trays and display parts
- Easy to trim and cut
- Not ideal for high-strength or outdoor applications
Best uses
Vacuum formed trays, display parts, packaging-related components, lightweight covers, and prototypes.
Expanded PVC
Overview
Expanded PVC is a lightweight, rigid foam PVC sheet used for signage, graphics, displays, exhibits, and printed panels.
Typical technical properties
- Forming temperature: not typically used for precision thermoforming
- Hardness: Shore D50–D60, depending on density
- Continuous service temperature: approximately 140°F–160°F
- Weight: lightweight compared with solid PVC or acrylic
- Moisture resistance: good
- Printability: excellent
- Rigidity: good for signage/display applications
- Mechanical strength: lower than solid plastics
Processing notes
- CNC routes well
- Cuts easily
- Prints well
- Good for signs and display panels
- Not for high-load mechanical parts
- Should not be CO₂ laser cut due to chlorine-containing fumes
Best uses
Signage, printing, display panels, exhibits, routed letters, point-of-purchase displays, and graphics substrates.
PVC Type I
Overview
PVC Type I is a rigid plastic with strong chemical resistance. It is often used for industrial, chemical, tank, duct, and utility applications.
Typical technical properties
- Forming temperature: approximately 250°F–325°F
- Hardness: Shore D75–D85
- Continuous service temperature: approximately 140°F–160°F
- Chemical resistance: very good
- Moisture resistance: very good
- Rigidity: good
- Impact resistance: moderate
- Flame resistance: generally good compared with many plastics
Processing notes
- CNC routes and machines well
- Can be fabricated and welded
- Often mechanically fastened or solvent welded
- Should not be CO₂ laser cut due to chlorine-containing fumes
- Not used for clear visual parts
Best uses
Chemical-resistant panels, industrial components, tanks, ducting, utility parts, and fabricated PVC components.