What You Need to Know About PMMA (Acrylic)

Key Takeaways

• PMMA offers the highest level of clarity among plastic resins, featuring a light transmittance rate of over 90%.

• PMMA is vulnerable to impact and prone to cracking or chipping on impact. 

• While PMMA is resistant to acids, contact with organic solvents or strong alkalis can cause cracking or discoloration.

Features of PMMA

PMMA (Polymethyl Methacrylate), commonly known as acrylic, is a commodity plastic that boasts the highest level of transparency among all resin materials. It features exceptional light transmission, with a total light transmittance rate exceeding 90%, making it a popular choice for lenses, covers, and lighting fixtures. It also offers excellent weatherability, meaning it won't easily discolor or degrade even under prolonged outdoor UV exposure.

When comparing transparent materials, note that polycarbonate offers vastly superior impact resistance, making it the preferred choice for applications where extreme durability is required. Additionally, PMMA's continuous operating temperature ranges from 80°C to 90°C (176°F to 194°F), meaning it does not handle high-heat environments well.

• Industry-leading transparency among plastic materials

• Excellent weatherability

• Strong electrical insulation properties

PMMA Grades

Beyond the standard option, PMMA is available in specialized grades engineered for enhanced performance:

• Standard grade

• Anti-static grade

• Impact-resistant grade

Considerations for Material Selection

PMMA is relatively brittle, making it prone to cracking or chipping upon impact. Its surface is also highly susceptible to scratching; abrasive contact can quickly compromise its optical clarity. Chemically, while it stands up well to acids, it has poor resistance to strong alkalis and organic solvents. For instance, using alcohol to clean acrylic partitions can trigger chemical cracking (crazing), leading to immediate fracturing or discoloration.

• Low impact and friction resistance

• Prone to surface scratching

• Vulnerable to strong alkalis and organic solvents

Step Up Your Project with Yumoto Electric

Yumoto Electric manufactures custom PMMA machined parts starting from a single piece. We have experience with over 200 materials, including metals such as aluminum alloys, stainless steel, molybdenum, and titanium; and engineering plastics including PEEK, POM, and MC Nylon.

If you’re unsure about material selection or machining methods, we offer complimentary consultations to help optimize your design and production. For any questions, please feel free to contact us.