Poly (methyl methacrylate) is the scientific name for the synthetic polymer commonly known as PMMA acrylic, acrylic glass, and plexiglass. When not modified it is brittle, transparent, and lightweight. It transmits light and when modified it is available in a wide range of color casting options, textures, and forms. It was first discovered in 1893 by a French chemist, but its commercial application was not widespread until 1993 when Otto Rohm brought it to market as a product known as Plexiglas.

Chemical structure of PMMA
 

Scientific Properities

PMMA has a melting point of 320°F and has a density range of 1.17-1.20 g/cm3. It experiences no reactions by aqueous solution when compared to other polymers and plastics it has a high scratch resistance. Often if the surface of the material constructed from PMMA is compromised, it can be attributed to exposure to aromatic or chlorinated hydrocarbon, ester, or ketone chemicals.

 

Sound-Resistant and Break-Resistant

PMMA can reduce transmissions of external sound waves, making it sound-resistant. It is beneficial insulator when constructing areas that intend to include internal sound and exclude external sound. A few examples of this would be audio studios, libraries, quiet rooms, and even cars.

 

Due to its durability, PMMA is less likely to break than its glass equivalent. Because it is break-resistant it is a great substitute for glass when building windows, domed skylights, signage, and displays.

 

Environmental Sustainability

PMMA is very useful for outdoor use. It will not corrode, and it is resistant to ultraviolet light, weather, and most other environmental factors. PMMA is one of the safer plastics, being both recyclable and BPA free. This makes PMMA considerably sustainable.

 

How is PMMA made?

PMMA is made through a process called polymerization. The methyl methacrylate is placed into a mold along with a catalyst that is added to speed up the process. Due to this process, PMMA can be shaped into many forms such as sheets, blocks, resins, and beads. If desired, acrylic glue helps soften the pieces and weld them together.

 

PMMA can be easily manipulated in many ways. It can be bonded to other materials, which can help enhance its properties. Through thermoforming, it is pliable when heated and solidified when cooled. It can be properly sized through the use of a saw or laser cutting. If polished, any scratches will be removed from the surface helping to maintain its integrity.

 

What is PMMA used for?

Many industries use PMMA because it is very versatile. Here a few common applications:

 

Home Improvement & Architecture

When it comes to construction, PMMA comes in very handy. It is often the choice for shatterproof skylights. It can also be found in many shower and bath units, many even prefer acrylic to ceramic tiles. As mentioned earlier, acrylic can be found in many sound-resistant rooms, audio studios, and cars.

Display case made from acrylic
 

DIY Projects

Whether it be for work or leisure, PMMA is a great material for DIY projects. PMMA is easy and safe to work with, it can be used in constructing art structures and various designs. Acrylic can be found in many DIY picture frames, coasters and shelving units. In addition, it is a great protective and aesthetically pleasing table cover.

 

Windows

Acrylic is a lighter material, making it easier to install than other options such as glass. Additionally, PMMA does not easily break and even if a plexiglass window were to break, it would create dull-edged pieces instead of sharp shards.

 

PMMA VS. Glass

When compared to glass PMMA is 50% lighter, 90-92% clearer, more durable and more affordable. It can retain its properties over a long period of time even when exposed to UV rays and weather. In addition, PMMA is scratch resistant. Glass tends to be delicate as it scratches and breaks easily. When it does break, it shatters into many sharp shards. Not only is this inconvenient, but it also dangerous. Acrylic on the other hand is both scratch and shatter resistant. For the reasons stated above many opt for PMMA as a substitute for glass.

 

PMMA VS. Polycarbonate

Polycarbonate is typically produced through extrusion manufacturing. It is more durable than acrylic and polycarbonate is non-flammable and highly resistant to chemicals. Polycarbonate would be better suited for a project that requires a nearly indestructible material such as bullet-resistant windows or hockey rink barriers.

PMMA is clearer and shinier than polycarbonate. When compared to polycarbonate PMMA is better at transmitting light, BPA free and it is more affordable than polycarbonate. PMMA would be better suited for retail displays or as a replacement for glass such as shatterproof windows or the walls of a fish tank

 

Additional PMMA Resources