POLYCARBONATE VS ACRYLIC: CHOOSING THE PERFECT PLASTIC
Introduction
Polycarbonate and acrylic are two of the most versatile and widely used plastics across a variety of industries. Both offer useful properties like strength, clarity, and weather resistance that make them suitable for countless applications.
While they share some similarities, polycarbonate and acrylic also have distinct differences that impact their performance in different situations.
This article provides an overview of the key similarities and differences between these two popular plastics. It aims to help designers, engineers, manufacturers, and hobbyists understand the unique advantages and limitations of each material.
With this knowledge, you'll be better equipped to select the right plastic for your specific needs and design goals. Whether you need exceptional impact resistance or pristine optical clarity, polycarbonate and acrylic each offer specialized benefits worth considering.
Impact Resistance
Polycarbonate has exceptional strength and impact resistance compared to acrylic. It is virtually unbreakable, making it an ideal material for applications that require high durability and resilience against breakage.
Polycarbonate can withstand extremely high impacts and shocks without cracking or shattering. In standardized impact resistance tests, polycarbonate can handle over 100 times more impact force than acrylic before fracturing.
This unmatched toughness is why polycarbonate is commonly used for protective equipment like safety goggles, riot shields, hockey masks, and bullet-proof windows.
An acrylic sheet of the same thickness would easily crack or completely shatter under the same impacts that polycarbonate can brush off.
Polycarbonate derives its incredible impact strength from the molecular structure of the plastic. The molecules bond tightly together, allowing the material to flex and stretch without snapping.
Polycarbonate also maintains its durability across a wide range of temperatures, unlike more brittle plastics that get weaker in cold conditions when impacted. This reliability makes polycarbonate an ideal material for applications that demand both high strength and resilience in varying environments.
Whether someone needs a plastic tough enough to stop a bullet or prevent a hockey puck from doing damage, polycarbonate is by far the best choice over breakable acrylic.
For applications where preventing impacts is crucial for safety and performance, polycarbonate is the clear winner.
Optical Clarity
Acrylic is well-known for its superior optical clarity compared to many other plastics. With light transmittance nearing 90-92%, acrylic allows almost as much light to pass through as glass.
This exceptional transparency makes acrylic an ideal choice for any application where optimal light transmission and a crystal clear view are desired.
The high-gloss finish of acrylic also enhances its visual appeal. When polished or extruded, acrylic achieves a smooth, glass-like surface that further contributes to its optical qualities. This lustrous look allows acrylic to mimic glass while providing a safer, more resilient alternative.
Acrylic's optical virtues make it a go-to choice for products like point-of-purchase displays, signage, furniture, cosmetic packaging, lenses, and aquariums.
Any application where clarity and brilliance are essential will benefit from acrylic's light transmitting properties and flawless finish. When optical performance is a top priority, acrylic outshines polycarbonate and most other plastics.
Cost
When it comes to cost, acrylic is generally the more affordable option compared to polycarbonate. Acrylic sheets and rods can cost 20-50% less than comparable polycarbonate materials.
This makes acrylic a great budget-friendly choice for applications where extreme impact resistance or heat tolerance are not required. The lower price point allows designers, manufacturers, and hobbyists to create more acrylic projects and products without breaking the bank.
Polycarbonate's superior durability and performance does come at a higher price. The raw polycarbonate material costs more to produce compared to acrylic. Additional processing and machining also adds to polycarbonate's price tag.
However, for products where safety is paramount, like riot shields, bulletproof glass, or other high-impact uses, polycarbonate remains the go-to plastic despite the higher cost. The added investment brings unmatched strength and resilience.
For large volume production runs, the lower per-unit cost of acrylic can make it far more affordable than polycarbonate. But for small scale prototyping or shorter runs, the price difference between the two is less significant.
Overall, acrylic offers excellent optical clarity and transparency at a budget-friendly price point. Polycarbonate provides maximum durability and performance albeit at a premium price. Consider cost trade-offs between the two materials based on production scale, application requirements, and budget constraints.
Heat and Chemical Resistance
Polycarbonate has much higher heat resistance compared to acrylic. It has a glass transition temperature around 147°C and can withstand prolonged exposure to temperatures up to around 120°C without any significant effects, whereas acrylic begins to soften at temperatures above 80°C.
Polycarbonate also has excellent chemical resistance properties and is unaffected by most mineral acids, alkalis, aliphatic hydrocarbons, and alcohols. Acrylic is prone to cracking or crazing when exposed to many common solvents and chemicals.
The superior heat and chemical resistance of polycarbonate makes it suitable for demanding applications where the material needs to withstand higher temperatures or exposure to harsh chemicals and solvents.
Polycarbonate lenses, screens, and shields maintain their strength and optical clarity even when subjected to oils, fuels, or caustic cleaning agents, allowing them to perform reliably in industrial environments.
Products made from acrylic would degrade rapidly under similar conditions. When heat or chemical resistance is a priority, polycarbonate is generally the better material choice over acrylic.
Fabrication
Acrylic is generally easier to fabricate and shape compared to polycarbonate. Acrylic can be thermoformed or heat bent into various shapes relatively easily, making it versatile for producing contoured forms.
It can be laser cut with precision for applications like signage and displays. Acrylic also lends itself well to techniques like cementing and polishing.
In contrast, polycarbonate is more difficult to work with and requires specialized fabrication techniques. It has a very high melting point, so heating and shaping polycarbonate requires considerably higher temperatures.
Polycarbonate also tends to fracture when laser cut, so it needs to be worked around. Overall, acrylic provides a much more fabrication-friendly material compared to polycarbonate.
Scratch Resistance
Polycarbonate is more prone to scratches than acrylic. Even small particles can leave marks on polycarbonate's surface. On the Mohs hardness scale, polycarbonate rates around 3 compared to around 2.5 for acrylic. This makes polycarbonate more likely to get scratched during handling, fabrication, installation, and everyday use.
Acrylic's softer surface is less susceptible to marring and abrasions. For applications where surface durability and aesthetics are paramount, such as transparent barriers or glazing, acrylic's scratch resistance gives it an advantage over polycarbonate.
However, there are coated polycarbonate products that can approach acrylic's scratch resistance. Overall, for applications where scratches may detract from appearance or performance, acrylic is the safer choice over standard polycarbonate.
Applications
Polycarbonate is the ideal material for applications that require high impact strength and durability, such as:
- Safety goggles and face shields
- Riot shields and body armor
- Bulletproof and blast-resistant windows and lenses
- Machine guards and shields
- Skylights, canopy glazing, and construction panels
- Vehicle headlights, taillights, and instrument covers
- Electronic component housings and covers
Acrylic excels in applications where optical clarity and fabrication are key requirements, including:
- Retail displays and signage
- Furniture, fixtures, and lighting covers
- Aquarium and terrarium tanks
- Sanitary ware and bathroom fixtures
- Lenses, prisms, and optical instruments
- Cosmetic packaging and displays
- Trophy and award covers and frames
The ideal applications showcase the unique strengths of each material - polycarbonate for impact protection and acrylic for optical clarity. Consider your specific needs to choose the right plastic.
Conclusion
When deciding between polycarbonate and acrylic for your application, it is essential to consider the key differences between these two versatile plastics. Polycarbonate is unmatched for strength and impact resistance but has less optical clarity.
Acrylic excels in optical properties and ease of fabrication but cannot withstand high temperatures or harsh chemicals. Polycarbonate is generally more expensive but offers superior durability. Acrylic provides great value but is prone to scratching.
The ideal choice depends on your specific requirements. Polycarbonate is perfect for applications demanding bulletproof or unbreakable materials like protective equipment and riot gear. Acrylic shines when high light transmittance is needed for displays, signage, lenses, or transparent structures.
Consider the operating environment, clarity needs, budget, and fabrication requirements. Test any unsure applications.
With an understanding of their distinct properties, you can select the right plastic for your particular project. Do not hesitate to reach out for assistance in determining the optimal material for your needs.
Looking for help choosing between polycarbonate or acrylic for your specific application? Our team of plastic experts is here to help!