What are the main disadvantages of polycarbonate sheets?

The main disadvantages are: 1) Scratches easily without protective coating, 2) More expensive than acrylic, 3) Vulnerable to certain chemicals like solvents, 4) Expands and contracts with temperature changes, 5) Can yellow over time without UV protection.

Does polycarbonate scratch easily?

Yes, uncoated polycarbonate scratches more easily than acrylic or glass. However, polycarbonate with hard coating (available from Plastics Canada) significantly improves scratch resistance for high-traffic applications.

What Are the Disadvantages of Polycarbonate Sheets?

The Main Disadvantages of Polycarbonate

While polycarbonate sheets are incredibly strong and durable, they do have some drawbacks you should consider:

1. Scratch Sensitivity

The biggest downside: Uncoated polycarbonate scratches much more easily than acrylic or glass. This makes it less ideal for applications where the surface will be frequently touched or cleaned.

Solution: Choose polycarbonate with hard coating for improved scratch resistance, or use acrylic for display cases and signage where clarity is critical.

2. Higher Cost Than Acrylic

Polycarbonate typically costs 30-50% more than acrylic of the same thickness. For budget-conscious projects where impact resistance isn't critical, acrylic may be the better choice.

3. Chemical Sensitivity

Polycarbonate is vulnerable to damage from certain chemicals including:

Acetone and other ketones
Strong alkaline solutions
Aromatic hydrocarbons (benzene, toluene)
Some window cleaners containing ammonia

Always use mild soap and water or cleaners specifically designed for polycarbonate.

4. Thermal Expansion

Polycarbonate expands and contracts more than glass with temperature changes. Proper installation requires allowing room for expansion to prevent buckling or cracking at fastening points.

5. UV Yellowing (Without Protection)

Uncoated polycarbonate will yellow and become brittle when exposed to UV rays. However, all polycarbonate sheets from Plastics Canada come with UV protection as standard, preventing this issue for 10+ years.

6. Slightly Lower Optical Clarity

Polycarbonate has 88% light transmission compared to acrylic's 92%. For most applications this difference is negligible, but for high-precision optical applications, acrylic or glass may be preferred.

When to Use Alternatives

Consider using acrylic or glass instead of polycarbonate when:

Scratch resistance is more important than impact resistance
Maximum optical clarity is required
Budget is a primary concern and impact isn't a risk
The application involves exposure to incompatible chemicals

The Bottom Line

Despite these disadvantages, polycarbonate remains the best choice for outdoor roofing, safety glazing, and any application where impact resistance is critical. The key is understanding your specific requirements and choosing the right material for your needs.