What is Acrylic Plastic? (PMMA)
Acrylic plastic, also called PMMA (Polymethyl methacrylate), is a transparent thermoplastic material known by its chemical name “plexiglass,” with excellent strength, rigidity, and optical clarity. The material has many similarities with Polycarbonate and, due to its high impact resistance, is also heavily utilized as a replacement for glass.
One key difference between acrylic and polycarbonate is that the former doesn’t contain the potentially harmful substance bisphenol-A (BPA), and the latter has greater impact strength.
The one feature which differentiates acrylic from other transparent plastics is its excellent weathering properties. Acrylic plastic sheets are easy to process, blend very well with most organic solvents and adhesives.
The supreme optical properties make it one of the clearest plastic on the market. Advantageous transparency makes it suitable for various applications.
Today, most acrylic plastic is sold in the form of sheets of varying thickness depending on the applications, but it can also be found in the form of rods or tubes. The stylized frosted, non-glare, and mirrored versions are making the rounds in the market too.
The History of Acrylic Plastic –
The transparent thermoplastic was introduced in 1928 by three chemists named William Chalmers, Otto Röhm, and Walter Bauer. and was adopted by the US in 1933 by a company named Rohm and Hass Company.
One of the first applications was made in WWII in submarine periscopes, airplane windows, and canopies. Even then, acrylic proved to be safer for airmen than glass.
How is Acrylic made?
Acrylic is made the way like other plastic materials. It all starts with the filtration of hydrocarbon fuels into lighter groups called “Fractions.” Some of those extracted fractions are reacted with certain catalysts to get acrylic(the same process called polymerization is used to make all the thermoplastic and thermoset materials) using polymerization.
Key Properties of Acrylic Sheets and Plastic –
Acrylic has various unique properties making it ideal for a variety of applications. Here are the typical properties of acrylic( We’ll discuss the grades and properties later in the piece):
- High optical clarity
- Fantastic chemical resistance to all solvents
- Excellent dimensional stability
- Good weatherability and UV resistance
- High impact resistance
|Melt Temperature||130°C (266°F)|
65 MPa (9400 PSI) ***
0.2 – 1% (.002 – .01 in/in) ***
90 MPa (13000 PSI) ***
Typical Injection Mold Temperature
79-107°C (175-225°F) ***
Water absorption (immersion 24 hours)
Heat deflection temprature
95°C (203°F) at 0.46 MPa (66 PSI) **
Why is Acrylic used so often?
Acrylic is one of the sought-after transparent thermoplastics in the market. The optical clarity and scratch resistance make it perfect for both outdoor and indoor applications.
It is a pocket-friendly lighter alternative to glass; yes, it is cheaper than polycarbonate and should be considered where strength is not an important factor. It can be easily cut into precise shape using laser energy as PMMA vaporizes in the laser’s contact.
I would recommend using acrylic when optical clarity is of utmost importance; if strength is also an important factor, more preference should be given to Polycarbonate.
Acrylic Grades and Applications –
Acrylic or PMMA is available in various grades, each with different properties, suitable for different applications. Here are the most common acrylic plastic grades.
Extrudes acrylic is the commonly found grade or variation of acrylic manufactured in length resulting in cost savings as yield loss can be slashed when parts are cut from custom sheet sizes. This type of acrylic sheet blends seamlessly with cement solvents.
Cast acrylic sheet has greater chemical resistance and fabulous machine processing capabilities compared to extruded acrylic.
Extruded and cast are the most commonly known acrylic variations. Let’s see a brief comparison between them:
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Better range n terms of thickness upto 4″, especially those made for bullet resistance
|Phemonelol optical properties||
Better long-term resistance for UV exposure and weather
Decent electrical and UV resistance
|Lightweight and rigid|
|Impact resistance better than glass(Not Kidding)||
Lower water absorbtion
Continuous Cast Acrylic:
Quite similar to cast acrylic in terms of chemical resistance and machining capabilities, continuous cast acrylic provides more defined thickness and larger, broader sheet sizes due to the continuous cast manufacturing method’s nature.
Acrylic for Architectural Applications:
Acrylic’s impact resistance, lightweight, weather resistance, and most importantly, its clarity an ideal material for housing and office applications. It is mostly used for making windows, partitions, canopies, lighting fixtures, etc.
OPTIX® DA Acrylic for Digital Printing:
OPTIX DA is extremely useful in UV protection without any need for adhesion promoters.
AMGARD™ Acrylic for Safety Shields:
It’s a transparent sheet coated with a silver ion antimicrobial agent that helps curb microorganisms like bacteria, mold, and fungi that will keep the product from staining and odor.
OPTIX® 95 Acrylic:
OPTIX 95 is mostly used for decorative purposes as it comes with a matte finish. Widely used in display products as it also reduces surface reflections. Stain and fingerprint resistance improves its applicability even more.
OPTIX® Flexilume Specialty Film:
Another variant with a matte finish and excellent uniformity. OPTIX® Flexilume film is highly utilized as an overlapping film for lenses or as a forming insert for forming metals and profiles.
OPTIX® LD Acrylic for Light Diffusion:
OPTIX® LD has supreme diffusion properties and weather resistance. Those features allow higher design flexibility with slimmer letters. Visible hot spots and splendor fluctuations are removed without affecting the light transience.
OPTIX® Pattern 12 Panels:
OPTIX® pattern 12 acrylic panels for lighting provide phenomenal efficiency and good glare control, not compromising the attractive appearance. The PL-21 sports a conical pattern in flexible sizes. It fits standard ceiling grids without much hassle for installation.
Advantages of Acrylic Plastic –
- Lighter but Stronger
- Easy to Maintain
- Easy to process and Shape
#1 Lighter but Stronger:
The greatest advantage of using acrylic plastic over glass is its lightweight. It’s 50% lighter than glass but more durable and stronger. Processing acrylic in the cast or extruded form will not only cut costs but will provide 10 times more toughness than glass.
From a safety point of view, if, in any case, an acrylic sheet product will break, it won’t shatter but will fracture into large dull(blunt) pieces.
That feature diversified its applicability to products like windows, shower doors, sliding doors, etc.
#2 Easy to Maintain:
As far as the cleaning and maintaining part is concerned, some usually unspoken rules need to be followed. Acrylic should always be cleaned or wiped with a wet microfiber cloth.
Using rough towels is also not recommended as they will create more scratches rather than removing them. Artificial cleaners are not be used as the chemicals in them will roughen the acrylic’s surface. Soapy water and Novus products will be an ideal choice for cleaning.
Bonus Tip – It is recommended to clean the cloth itself with water to remove particles and grits because they can be responsible for leaving or enhancing the scratches on the acrylic’s surface.
#3 Easy to Process and Shape:
Acrylic plastic, when heated, becomes soft and moldable into various shapes, forms, and sizes. As it cools, it becomes hard and holds a formed shape, becoming easier to be machined.
The molds used are often made from metal or even wood. The process is very in-expensive and versatile as acrylic sheets can easily be bent into many shapes.
Disadvantages of Acrylic Plastic –
- It scratches more often than glass.
- Easily stained by greases and oil. However, as I mentioned above, cleaning acrylic is also very easy.
- Distortion is another problem that can be very negative for some people because acrylic bends very easily during construction.
- Compared to thermoplastics, matte resistance is not at par.
Is Acrylic Toxic?
For toxicity, acrylic comes with the major benefit that it doesn’t contain or release Bisphenol A (BPA) during hydrolysis. On the other side, Polycarbonate does contain BPA. Although the overall impact of BPA is still unclear, it still gives acrylic an edge over PC.
The government research studies conclude that acrylic is toxic for humans, but as the private sector(plastic Processing companies) research goes, the harm is exaggerated in the government reports.
However, while processing acrylic or even polycarbonate, a safe distance should be maintained from the machine and the released fumes. Wearing a mask can be a good option to avoid fumes.
The processing should be done in a well-ventilated facility to avoid any unwanted casualties.
The Future of Acrylic –
According to a Market Research Future study, the global Acrylic market will register a CAGR of 5.5 % and reach USD 6 billion by 2027.
The number can show drastic change because, as of writing this post, the Covid-19 pandemic is still on and has left a staggering impact on the world economy and manufacturing.
But if we look with a long-term perspective, the future looks bright because of rapid acrylic adoption by various sectors worldwide. The largest consumer of acrylic is the building and architecture industry will continue to hold a large chunk of market share in the future.
Other important industries would be communications, retail, automotive, and furniture & design. Their contribution to acrylic consumption will see a study rise in the near and long-term future.
North America is the biggest consumer of acrylic, followed by Europe and Asia. However, Asia can become a more dominant player in the future thanks to excellent economic growth and changing lifestyles.
1. What is the molecular structure of acrylic?
2. Can acrylic be easily shaped?
Ans. Acrylic is easy to fabricate and shape. It also has good machining properties reason for its good shaping properties and its ability to become soft under high temperatures.
3. What is heavier? glass or acrylic?
Ans. Glass is twice as heavier as acrylic and that makes acrylic ideal for many applications where the traditional choice was glass. The construction industry is a very good example where acrylic is quickly replacing glass.
4. Is acrylic harder than plywood?
Ans. Acrylic is said to be 30 times harder than a half-inch plywood sheet.
5. Is acrylic heavier than MDF?
Ans. Acrylic is denser than MDF, making acrylic at least a pound heavier. To be accurate, the acrylic platter has 0.125% wow & flutter compared to 0.175% for MDF. However, acrylic has a cleaner and more detailed sound. Acrylic is also great at decreasing unwanted vibrations because of its high density and low stiffness.
The Takeaway –
Finally, I would like to say that utilizing acrylic plastic and sheets proves exceptionally beneficial for manufacturers. I have tried my best to keep this post brief and informative.
I hope you liked it. Kindly share your reviews in the comment box.