Acrylic (PMMA) is a clear, lightweight engineering plastic that is known for being very weather-resistant, having a glass-like transparency, and being very hard on the surface. It is easy to machine, mold, and laser-cut, and it is often used for display windows, lighting parts, protective covers, and the cases of consumer products.
Acrylic is a great choice for modern engineering and product design because it has high clarity (up to 92% light transmission), good UV stability, and is lighter than glass or polycarbonate. It also has a good balance of performance, looks, and ease of manufacture.
What Is Acrylic? Definition, Material Structure, and Types
Acrylic (PMMA) Material Definition
PMMA (Polymethyl Methacrylate) is a clear, amorphous thermoplastic that is part of the polyacrylate family. Acrylic plastic is the name used in business. It is one of the clearest and most common optical polymers. Plexiglas®, Lucite®, and Perspex® are some of the most common trade names for acrylic.
Acrylic looks like glass, but it is actually a type of plastic. It is an engineering thermoplastic that gets softer when heated and harder when cooled. It has a density of about 1.18 g/cm³, which is less than half that of glass. However, it has a great strength-to-weight ratio and better optical performance. This is why it is often used for lenses, lighting diffusers, instrument covers, and display panels.
Terminology Note: “Acrylic plastic” refers to PMMA solid materials (sheets, rods, or molded parts), while “plexiglass” is simply a trade name for cast acrylic sheets. Both are chemically identical PMMA materials.
Chemical Structure and Optical Clarity Mechanism
The chemical backbone of PMMA consists of repeating units of methyl methacrylate monomers, forming long, linear carbon chains with pendant methyl and ester groups. This structure lacks crystallinity, resulting in an amorphous morphology—the key reason for its exceptional optical clarity, allowing up to 92% visible light transmission, surpassing standard glass.
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Amorphous structure: No crystalline boundaries to scatter light → high transparency
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Rigid carbon backbone: Provides surface hardness and dimensional stability
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Methyl side groups: Limit chain mobility, leading to moderate brittleness
However, residual stresses introduced during machining, molding, or polishing can cause microcracking or crazing—a common issue in optical-grade acrylic parts. Controlled annealing (e.g., 80–90°C for several hours) is recommended to relieve stress and prevent future cracking.
Cast vs Extruded Acrylic (Critical for Engineers)
Acrylic materials are commercially available in two main manufacturing forms—cast (cell-cast) and extruded—each with distinct processing and performance characteristics.
| Property / Feature | Cast Acrylic (Cell Cast) | Extruded Acrylic (Continuous Extrusion) |
| Optical Quality | Excellent (optically pure) | Good (slight flow lines possible) |
| Thickness Uniformity | Less consistent | Highly uniform |
| Surface Hardness | Higher | Slightly lower |
| Chemical Resistance | Excellent (resists solvents better) | Moderate (sensitive to solvents) |
| Machinability | Better for CNC cutting and polishing | Softer, easier to laser cut |
| Cost | Higher | Lower |
| Applications | Lenses, optical components, display windows | Signage, panels, housings |
Engineering Insight:
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Cast acrylic is preferred for optical-grade components, lenses, and precision-machined parts, due to its clarity and resistance to solvent-induced stress cracking.
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Extruded acrylic offers better cost efficiency and consistency, making it ideal for mass-produced enclosures, light panels, and signage.
In summary, acrylic (PMMA) is a lightweight, glass-like thermoplastic whose amorphous molecular structure delivers superior transparency and surface hardness. Understanding the differences between cast and extruded grades is essential for selecting the right material in optical, mechanical, or consumer product applications.
Key Properties of Acrylic: Optical, Mechanical, Thermal, and Chemical Behavior
Optical Properties
Acrylic (PMMA) is one of the clearest transparent plastics available, transmitting up to 92% of visible light—higher than both polycarbonate (PC) and standard glass. Its refractive index (~1.49) ensures excellent light diffusion and optical consistency, making it ideal for display lenses, lighting covers, and optical panels.
In addition to clarity, acrylic has superior surface hardness compared to PC, which helps resist scratches and maintain long-term optical integrity without coating. The optical stability of PMMA under UV exposure is another major advantage: unlike polycarbonate, acrylic does not yellow easily when exposed to sunlight, making it the preferred choice for outdoor applications such as skylights and light fixtures.
Mechanical Properties
Acrylic exhibits high stiffness and moderate strength, but its impact resistance is lower than that of polycarbonate. While PC can absorb heavy impacts without fracturing, PMMA tends to crack under sharp or concentrated stress, which limits its use in heavy-duty or impact-critical components.
| Property | Typical Value | Engineering Implication |
| Tensile Strength | 60–75 MPa | High rigidity and dimensional stability |
| Flexural Modulus | 2,400–3,000 MPa | Excellent stiffness |
| Izod Impact (notched) | 15–20 J/m | ~10× stronger than glass but < PC |
| Density | 1.18 g/cm³ | Lightweight and easy to handle |
Another critical mechanical aspect is creep behavior—under long-term load, PMMA shows cold flow (creep deformation), especially near its glass transition temperature. Engineers designing mounting structures or fastened assemblies must account for load relaxation over time, using reinforced inserts or load-distributing geometries.
Thermal Properties
Acrylic has a glass transition temperature (Tg) of approximately 105°C, above which it softens and begins to deform. The melting range is around 160–180°C, depending on molecular weight and additives. Its thermal expansion coefficient (~7×10⁻⁵ /°C) is relatively high, meaning dimensional changes can occur during machining or when used in high-temperature environments.
In CNC machining, this property necessitates temperature control and moderate feed rates to prevent warping or internal stress buildup. Acrylic is not recommended for sustained use above 80–90°C, as prolonged exposure may lead to thermal distortion or surface crazing.
Chemical Resistance and Environmental Stability
Acrylic performs exceptionally well in outdoor and UV-exposed environments, far exceeding PC in weather resistance. It maintains clarity, gloss, and color stability even after long-term exposure to sunlight and humidity. This makes it the material of choice for architectural glazing, signage, and automotive lighting.
Chemically, PMMA is resistant to dilute acids, alkalis, and oils, but it is vulnerable to alcohols, ketones, and chlorinated solvents, which can cause stress cracking (Environmental Stress Cracking Resistance – ESCR). Engineers must avoid using solvent-based adhesives or cleaners that could initiate microcracks at stressed regions.
UV Aging Behavior: PMMA exhibits excellent UV stability due to its stable carbon–carbon backbone and lack of UV-absorbing chromophores. However, prolonged exposure at high UV intensity may gradually reduce impact strength. Using UV-stabilized or surface-coated acrylic grades can further extend service life in outdoor or optical applications.
In summary, acrylic (PMMA) provides exceptional optical clarity, stiffness, and UV stability, but requires careful mechanical and thermal design to avoid cracking, creep, and thermal distortion. For most engineering and consumer applications—where transparency, hardness, and weatherability are essential—PMMA remains the standard transparent engineering plastic.
Processing Acrylic: CNC Machining, Laser Cutting, and Molding Guidelines
CNC Machining Acrylic
Acrylic (PMMA) is one of the most machinable transparent plastics, but it requires precise tooling and process control to achieve high optical quality and prevent cracking or melting.
Tooling Requirements: Use razor-sharp carbide or PCD tools with a positive rake angle (5–10°) and polished cutting edges to minimize friction and heat buildup. Dull tools will cause surface whitening, melting, or edge chipping.
Cutting Parameters (Reference):
| Operation | Cutting Speed | Feed Rate | Depth of Cut |
| Roughing | 500–1,000 m/min | 0.1–0.3 mm/rev | 1–2 mm |
| Finishing | 800–1,500 m/min | 0.05–0.1 mm/rev | 0.5 mm |
Heat and Edge Control: PMMA has a low softening temperature (~100°C), so excessive friction can cause surface melting. Recommended techniques:
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Air cooling or mist lubrication (avoid oily coolant)
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Light cutting passes to minimize thermal stress
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Proper clamping to prevent vibration and warpage
To prevent edge chipping, maintain stable feed direction and avoid high-speed tool engagement near corners.
Finishing: After machining, surfaces can be polished to optical clarity using:
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Vapor polishing (chloroform vapor to reflow surface)
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Flame polishing (short oxygen-hydrogen flame for edge finishing)
Both methods restore transparency but must be applied carefully to avoid stress concentration or warping.
Laser Cutting Acrylic
Laser cutting is one of the most efficient ways to process acrylic sheets, offering precision and smooth optical edges. The CO₂ laser (10.6 µm wavelength) melts and vaporizes PMMA locally, producing a clear, glossy edge without post-polishing.
Mechanism and Quality:
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Thermal melting + vaporization produces mirror-like edges.
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The Heat-Affected Zone (HAZ) is narrow (~0.1–0.2 mm), but excessive power can cause microcracks or yellowing.
Cast vs Extruded Acrylic Behavior:
| Property | Cast Acrylic | Extruded Acrylic |
| Edge Clarity | Excellent | Slightly hazy |
| Cut Speed | Slower | Faster |
| Crack Resistance | Higher | Lower (prone to melt and bubble) |
| Optical Distortion | Minimal | Moderate |
Engineering Note: For optical components or precision enclosures, use cast acrylic. For signage or decorative panels, extruded acrylic offers better throughput and lower cost.
Injection Molding Acrylic (PMMA Molding Guidelines)
Acrylic can be injection molded with excellent clarity, but it demands tight temperature and flow control to prevent stress cracking and optical distortion.
Processing Window:
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Melt Temperature: 230–260°C
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Mold Temperature: 60–90°C (higher for optical-grade parts)
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Drying: 80–90°C × 2–3 hours before molding
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Injection Pressure: 80–120 MPa
Flow and Cooling Control: PMMA’s flowability is lower than PC, requiring well-balanced runners and uniform mold filling. Sudden flow interruption can cause weld lines or trapped air, which degrade transparency. Cooling should be slow and uniform to minimize internal stress and prevent ESCR (Environmental Stress Cracking) during service.
Gate Design Considerations:
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Use fan or edge gates for smooth filling
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Avoid pin-point gates in thick optical parts (stress riser)
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Maintain thicker edges to promote stress relief during ejection
Optical Mold Quality: For optical or transparent components, mirror-polished molds (Ra < 0.05 µm) and controlled mold temperature are essential to achieve distortion-free, high-clarity surfaces. Rapid cooling or poor venting can lead to flow marks, haze, or birefringence.
Summary for Manufacturing Engineers:
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CNC machining → Ideal for low-volume, high-precision optical components.
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Laser cutting → Best for signage, displays, and decorative shapes.
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Injection molding → Suitable for mass production of lenses and housings, requiring expert control of temperature, stress, and mold quality.
Each process demands different heat management and stress control strategies, but all benefit from cast acrylic’s superior optical stability and stress resistance.
Common Failure Modes and Engineering Solutions
Stress Cracking (Environmental Stress Cracking, ESC)
Stress cracking is the most frequent failure mode in acrylic (PMMA) components—particularly in transparent housings, displays, and medical or electronic enclosures. It results from a combination of internal residual stress and chemical attack.
Residual Stress Sources:
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Uneven cooling during injection molding
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Excessive clamping pressure during CNC machining
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Improper laser cutting without annealing
When internal stress interacts with external agents such as alcohol-based cleaners, adhesives, or organic solvents, microcracks form along the stress lines—often invisible until catastrophic fracture occurs. Alcohols (e.g., isopropanol), ketones (e.g., acetone), and chlorinated solvents attack PMMA’s amorphous polymer chains, accelerating crack propagation.
Engineering Solution — Annealing: To release residual stress, perform annealing at 80–90°C for 2–4 hours, followed by slow cooling. This allows molecular chains to relax and prevents ESC in service. For thick parts, temperature ramping (gradual heating and cooling) ensures uniform stress relief.
Preventive Tips:
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Avoid solvent-based cleaners; use mild soap solutions
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Use cast acrylic, which has better solvent resistance than extruded grades
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Incorporate fillets or rounded corners to minimize stress concentration
Optical Distortion and Surface Defects
Acrylic’s optical clarity can be compromised by several manufacturing-induced surface issues. These defects not only affect aesthetics but can also alter light transmission and create optical aberrations.
| Defect Type | Cause | Solution |
| Machining haze | Tool vibration or heat buildup during CNC cutting | Use sharp, polished tools; apply air cooling; polish after machining |
| Laser cut striations | Overpower laser settings or poor focus | Optimize cutting speed; ensure consistent beam alignment |
| Injection flow lines / weld marks | Uneven flow front during molding | Adjust gate design and injection speed; increase mold temperature for uniform filling |
Engineering Note: Transparent acrylic is particularly sensitive to birefringence—optical distortion caused by uneven stress distribution. For high-precision optical parts, control mold cooling, polish gate areas, and maintain uniform wall thickness to avoid internal refractive gradients.
Impact Fracture and Brittleness
Acrylic’s brittle failure is a result of limited chain mobility in its rigid, amorphous structure. When subjected to sudden impact, polymer chains break rather than deform, leading to a clean, glass-like fracture. Unlike ductile plastics, PMMA lacks energy dissipation through plastic deformation.
Fracture Mechanism:
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Rapid crack initiation at stress concentrators (sharp corners, holes, or notches)
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Chain scission under high localized stress
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Crack propagation across the transparent matrix, often visible as “mirror” fracture surfaces
| Material Comparison | Izod Impact Strength (notched) | Behavior |
| Acrylic (PMMA) | 15–20 J/m | Brittle fracture |
| Polycarbonate (PC) | 600–850 J/m | Ductile deformation |
| Glass | <10 J/m | Immediate shatter |
Engineering Solutions:
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Use radiused corners and avoid sharp transitions
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Consider PC or modified PMMA blends (impact-modified acrylic) for high-impact parts
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Perform annealing post-machining or molding to reduce residual stress
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For enclosures or covers, increase wall thickness or add ribs to distribute load
Acrylic vs Polycarbonate vs PETG vs Glass — Engineering Material Selection Guide
Optical Properties Comparison
Acrylic (PMMA), Polycarbonate (PC), and PETG are all commonly used transparent engineering materials, but they differ significantly in optical clarity, surface finish, and light transmission behavior.
| Property | Acrylic (PMMA) | Polycarbonate (PC) | PETG | Glass |
| Light Transmission | 92% (highest) | 88–90% | 89% | 90–91% |
| Haze / Diffusion | Very Low | Moderate | Low | Very Low |
| Optical Stability (UV) | Excellent | Prone to yellowing | Good | Excellent |
| Refractive Index | 1.49 | 1.58 | 1.57 | 1.52 |
Engineering Takeaway:
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Acrylic delivers the best optical clarity and weatherability, ideal for lighting, signage, and display covers.
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PC maintains good transparency with added impact strength but may yellow under UV exposure.
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PETG provides a balance between clarity and processability for indoor components.
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Glass remains the optical benchmark but is heavy and brittle.
Impact Strength and Durability
When impact resistance and long-term mechanical reliability are critical, polycarbonate clearly outperforms other materials.
| Property | Acrylic (PMMA) | Polycarbonate (PC) | PETG | Glass |
| Impact Strength | Moderate (15–20 J/m) | Extremely High (600–850 J/m) | Medium (200–300 J/m) | Very Low |
| Brittleness | Brittle | Ductile | Semi-ductile | Very Brittle |
| Scratch Resistance | High | Low (requires coating) | Moderate | Very High |
| Service Life (Outdoor) | Excellent | Requires UV coating | Moderate | Excellent |
Engineering Takeaway:
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Polycarbonate (PC) → for impact-critical parts (machine guards, helmets, shields).
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Acrylic (PMMA) → for optically demanding but non-impact environments (light lenses, decorative panels).
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PETG → for medium-duty consumer and packaging parts.
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Glass → for architectural and high-clarity uses, when weight and brittleness are acceptable.
Processing and Manufacturability
Each material presents distinct behavior in CNC machining, laser cutting, and injection molding. Understanding these differences is key for DFM optimization.
| Process | Acrylic (PMMA) | Polycarbonate (PC) | PETG | Glass |
| CNC Machining | Easy, smooth edges | Requires cooling, prone to cracking | Easy | Not machinable |
| Laser Cutting | Excellent, glossy edge | Prone to yellowing | Excellent | Not suitable |
| Injection Molding | Stable flow, sensitive to cooling | High melt temperature | Very easy | — |
| Surface Hardness | High (2H–3H) | Low (soft) | Medium | Very High |
| Bonding / Adhesion | Poor (needs treatment) | Poor | Good | Excellent (adhesive-based) |
Engineering Takeaway:
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Acrylic → best for CNC or laser processes requiring high optical finish.
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PC → requires controlled molding but delivers strong structural integrity.
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PETG → ideal for vacuum forming and low-stress molding.
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Glass → limited manufacturability, suitable for static optical assemblies.
Cost and Application Scenarios
| Application / Requirement | Acrylic (PMMA) | Polycarbonate (PC) | PETG | Glass |
| Optical Lenses / Covers | ✅ Excellent | ⚪ Good | ⚪ Good | ✅ Excellent |
| Light Diffusers / Lamp Shades | ✅ Excellent | ⚪ Acceptable | ✅ Excellent | ⚪ Limited |
| Machine Guards / Impact Shields | ❌ Brittle | ✅ Excellent | ⚪ Moderate | ❌ Fragile |
| Consumer Electronics / Display Panels | ✅ Excellent | ✅ Strong | ✅ Cost-effective | ❌ Heavy |
| Outdoor Panels / Signage | ✅ UV Stable | ⚪ Needs coating | ⚪ Fair | ✅ UV Stable |
| Food / Medical Contact | ⚪ Limited | ⚪ Limited | ✅ Preferred | ✅ Safe |
| Cost Level (Relative) | Medium | High | Low–Medium | High |
Selection Recommendation
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Choose Acrylic (PMMA) when optical clarity, surface hardness, and UV resistance are priorities (e.g., light covers, signage, optical panels).
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Choose Polycarbonate (PC) for impact-resistant, load-bearing transparent components (e.g., machine shields, enclosures, safety visors).
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Choose PETG for cost-sensitive, formable parts where moderate clarity and toughness suffice.
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Choose Glass for premium optical quality or long-term stability, where weight and fragility are not limiting factors.
Engineering Summary: Acrylic strikes the best balance of clarity, cost, and weather resistance. Polycarbonate dominates impact-critical applications, PETG fits low-cost thermoformed parts, and glass remains the benchmark for optical purity. Selecting the right material depends on performance priorities, environmental exposure, and manufacturability constraints.
Applications of Acrylic in Industrial and Consumer Products
Optical Components
Acrylic (PMMA) is one of the most widely used materials for optical and lighting applications due to its exceptional light transmission (up to 92%), low birefringence, and excellent surface polishability.
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Light Diffusers: Used in LED lighting systems, automotive lamps, and architectural illumination. Cast acrylic provides uniform diffusion without color shift or glare.
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Lenses: Ideal for camera covers, sensor housings, and lighting lenses. PMMA maintains high dimensional accuracy and optical clarity even after CNC machining or injection molding.
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Display Windows: Used in instrument panels, electronic displays, and protective screens. Compared with glass, acrylic offers half the weight and ten times the impact resistance, while remaining optically pure.
Key Advantage: Acrylic combines optical-grade transparency with design flexibility—critical for optics, photonics, and electronic enclosure designs.
Architectural and Consumer Use
Acrylic has become a core material in architectural design and consumer products, valued for its UV stability, weather resistance, and surface finish quality.
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Glazing: A durable alternative to glass in skylights, canopies, and protective partitions. Acrylic resists yellowing and retains transparency after years of outdoor exposure.
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Signage: The most common substrate for illuminated and printed signs. Extruded acrylic sheets are lightweight, easy to laser-cut, and compatible with solvent or UV printing.
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Decorative Panels: Used in furniture, wall cladding, and interior lighting panels. Designers choose acrylic for its color versatility, polishability, and impact-resistant transparency.
Engineering Insight: Acrylic’s weathering resistance and UV stability outperform most plastics, making it ideal for outdoor or exposed environments where glass may shatter or discolor.
Engineering and Mechanical Use
Beyond aesthetics, acrylic also serves in functional mechanical applications requiring visibility and moderate strength.
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Machine Guards: Transparent safety barriers for CNC machines and laboratory equipment. Acrylic offers high stiffness, impact resistance, and excellent visibility for operator safety.
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Covers & Housings: Protective enclosures for instruments, meters, and equipment panels where light transmission and appearance matter.
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Custom CNC Parts: Acrylic is frequently used for prototype enclosures, flow visualization models, and precision fixtures, thanks to its excellent machinability and clean edge finish.
Summary: Acrylic bridges the gap between aesthetic design and engineering performance. It provides optical clarity, structural reliability, and chemical resistance, making it a top choice for lighting, architectural, and mechanical components across industries from consumer electronics to industrial automation.
Design for Manufacturability (DFM) Guidelines for Acrylic Components
Wall Thickness and Stress Control
Acrylic (PMMA) is a brittle, amorphous thermoplastic, which means internal stress can easily accumulate during molding or machining. Uneven wall thickness is one of the primary causes of residual stress concentration—leading to warping, cracking, or optical distortion.
Design Recommendations:
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Maintain uniform wall thickness across the entire part (recommended range: 2–6 mm for molded parts).
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Avoid sudden transitions in section thickness; use gradual tapers or fillets.
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In snap-fit or press-fit designs, stress localizes around retaining features—consider larger radii or reduced interference fits to prevent cracking.
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For thick components (≥10 mm), use annealing (80–90°C for 2–4 hours) to release internal stress after machining or molding.
Engineering Insight: Residual stress in transparent acrylic can manifest as optical birefringence or stress whitening. Proper wall design and post-processing are essential for optical-grade clarity.
Corner Radius and Geometry Recommendations
Sharp corners are the most common failure initiation points in acrylic components. Stress concentration at internal or external corners can cause microcracks and brittle fracture, especially under impact or solvent exposure.
Best Practices:
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Apply minimum internal corner radius ≥ 0.5 × wall thickness.
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Use filleted edges instead of sharp 90° angles in window cutouts and mounting holes.
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Add ribs or gussets to improve stiffness rather than increasing wall thickness.
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Avoid long, thin unsupported walls that can flex and induce tension.
Practical Tip: In optical or fluidic components, rounded transitions not only reduce mechanical stress but also improve flow uniformity and light transmission.
Tolerances and Dimensional Stability
Acrylic exhibits a relatively high coefficient of thermal expansion (CTE ≈ 7×10⁻⁵ /°C) and low elasticity, which affects dimensional accuracy—especially in precision CNC machining or optical assemblies.
| Manufacturing Method | Typical Tolerance Range | Notes |
| CNC Machining | ±0.05–0.1 mm | Best accuracy achievable with controlled temperature |
| Injection Molding | ±0.1–0.2 mm | Dependent on mold design and cooling uniformity |
| Laser Cutting | ±0.05 mm | Edges may show minor heat distortion |
Design Recommendations:
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When designing tight-fit assemblies, consider operating temperature variation (acrylic expands more than metals or glass).
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For optical covers or lenses, perform final machining or polishing at stable ambient conditions to prevent thermal-induced warping.
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Avoid over-constraining the part with multiple fasteners—allow for slight expansion gaps.
Engineering Takeaway: Successful acrylic component design balances mechanical strength, optical performance, and manufacturability. By managing wall uniformity, corner geometry, and tolerance planning, engineers can minimize internal stress, enhance clarity, and achieve long-term dimensional stability in precision applications.
Summary
Acrylic (PMMA) is a light, clear engineering plastic that lets through up to 92% of light. This makes it great for optical, architectural, and aesthetic uses. It can be machined and polished to make high-quality clear parts, but it is brittle, so careful design is needed to avoid cracking and distortion. This includes making sure the walls are thick enough, controlling stress, using large radii, and annealing the parts after they are made.
Cast acrylic makes lenses and display panels that are the clearest and most rigid. Extruded acrylic, on the other hand, makes signs and covers that are the same size at a lower cost. Acrylic is a great choice for both industrial and consumer-facing clear parts because it is clear, weatherproof, and affordable. It is also easy to work with and safe to use with solvents.
FAQ
What is acrylic plastic made of?
Acrylic, or PMMA (Polymethyl Methacrylate), is made from methyl methacrylate monomers polymerized into a clear, rigid thermoplastic. Its amorphous molecular structure gives it high optical clarity and good surface hardness.
Is acrylic a type of plastic?
Yes. Acrylic is a thermoplastic polymer, meaning it softens when heated and can be reshaped multiple times without losing transparency or structural integrity.
Why is acrylic used instead of glass?
Acrylic offers 92% light transmission, excellent weather resistance, and weighs less than half of glass, while being 10× more impact-resistant—making it ideal for glazing, displays, and protective covers.
Is acrylic stronger than polycarbonate?
No. Polycarbonate (PC) is tougher and more impact-resistant, but acrylic has higher scratch resistance, better UV stability, and superior optical clarity.
Can acrylic be CNC machined?
Yes. Acrylic is easy to machine, mill, or laser-cut, but requires sharp tools and low heat generation to avoid chipping or surface melting. Post-polishing restores optical transparency.
What are the differences between cast and extruded acrylic?
Cast Acrylic: Better optical quality, higher strength, and solvent resistance.
Extruded Acrylic: More uniform thickness and lower cost, but weaker against solvents.
Does acrylic scratch easily?
Yes. Although harder than polycarbonate, acrylic can scratch under abrasion. Surface coatings or hard-coated sheets are used for enhanced durability.
Is acrylic suitable for injection molding?
Yes, PMMA is moldable, but requires precise temperature and cooling control to prevent internal stress, optical haze, and cracking in transparent components.
About the Author: Gavin Xia
This article was written by engineers from the RAPID PROTOS team. Gavin Xia is a professional engineer and technical expert with 20 years of experience in rapid prototyping, metal parts, and plastic parts manufacturing.
