Acrylic and polycarbonate look almost identical on the shelf. In a finished part, they behave very differently. The right pick depends on how much impact, clarity, heat, and budget your application demands. Choosing wrong means cracked parts or money spent on strength you never needed.
This guide compares acrylic and polycarbonate for engineers and buyers specifying a fabricated plastic. We cover the core property differences and how to match the material to the job.
Key Takeaways
- Polycarbonate wins on impact strength; acrylic wins on clarity and cost.
- Acrylic scratches less easily; polycarbonate handles heat and stress better.
- The right choice depends on impact, optics, temperature, and budget.
What Is Acrylic?
Acrylic, also called PMMA, is a rigid, glass-clear thermoplastic. It offers excellent optical clarity, good weather resistance, and a lower cost than polycarbonate. It is stiffer but more brittle, so it can crack under sharp impact.
What Is Polycarbonate?
Polycarbonate is a tough, impact-resistant thermoplastic used where parts must survive abuse. It is far stronger than acrylic and tolerates higher temperatures. It costs more and scratches more easily without a hard coat.
Acrylic vs. Polycarbonate: The Core Differences
The two materials trade strengths. Here is how they compare on the factors that drive most decisions.
Impact Resistance
Polycarbonate is the clear winner. It resists cracking far better than acrylic and is the choice for guards, glazing, and high-abuse parts. Acrylic is rigid but can shatter under a hard hit.
Optical Clarity
Acrylic is the more transparent material and resists yellowing over time. It suits display cases, lenses, and signage. Polycarbonate is clear too, but can haze or yellow without UV treatment.
Machining and Fabrication
Both machine well, but they behave differently. Acrylic cuts and polishes to a crisp edge, ideal for clean optical finishes. Polycarbonate is more forgiving in drilling and cold-forming because it resists cracking.
Temperature and Cost
Polycarbonate handles higher service temperatures and continuous stress. Acrylic is more affordable and fine for ambient conditions. For background on each polymer, see the technical overviews of polycarbonate and acrylic (PMMA).
How to Choose for Your Application
Match the material to the dominant requirement, not to habit.
- Need maximum impact strength or safety glazing, choose polycarbonate.
- Need the best clarity, scratch resistance, or lower cost, choose acrylic.
- Unsure, share your specs and we will recommend the right grade.
Frequently Asked Questions
Is polycarbonate stronger than acrylic?
Yes. Polycarbonate has far higher impact resistance and is much harder to crack. Acrylic is stiffer but more brittle under sharp impact.
Which scratches more easily, acrylic or polycarbonate?
Polycarbonate scratches more easily and often needs a hard coat. Acrylic has better natural scratch resistance and surface clarity.
Is acrylic cheaper than polycarbonate?
Generally yes. Acrylic costs less, which makes it the value choice when extreme impact strength is not required.
Can both be CNC machined and polished?
Yes. Both fabricate well. Acrylic takes a crisper polished edge, while polycarbonate tolerates drilling and forming without cracking.
Get the Right Material Fabricated to Spec
The best choice comes down to your part’s real demands, not the material that is most familiar. Send us your application and tolerances and our team will match the polymer and grade. Wm. F. McGraw & Co. provides precision acrylic fabrication and polycarbonate fabrication, cut and finished to your drawings. Contact us to spec your next part with confidence.
