FAQ

Crystal-clear PMMA shows excellent resistance to aging and weathering, including natural UV radiation. Therefore they do not turn yellow or become brittle even after many years of outdoor exposure to various climates around the world. PMMA retains its superior optical and mechanical properties for many years

PMMA is generally characterized by good chemical resistance. Parts made from PMMA are resistant to most inorganic chemicals, aliphatic hydrocarbons, cycloaliphatic compounds, fats and oils at room temperature, and also to diluted acids and concentrated solutions of most alkalis at temperatures up to 60 degrees Celsius. By contrast, PMMA is attacked by chlorinated hydrocarbons, ketones, esters, ethers, alcohols and aromatic compounds.

PMMA shows the greatest surface hardness and thus the best abrasion resistance of all thermoplastics. The high gloss is therefore retained even after prolonged utilisation.

Optical properties

Since cast PMMA is manufactured by cell casting between two sheets of mirror-like glass, it has excellent surface quality. Extruded PMMA is manufactured in a special extrusion process and, therefore, cannot always match the high optical quality of cast PMMA.

Machining

Cast PMMA offers greater scope for fabrication, which means the machining conditions do not have to be observed with such accuracy. Less scope is available with extruded PMMA, and care must be taken to ensure the correct tools are used in order to obtain clean cuts and drill holes, if necessary using cooling lubricants.

Thermoforming

Extruded PMMA allows more economical solutions during thermo forming because the forming cycles are shorter and contours can be more accurately reproduced.

Permanent service temperature

The permanent service temperature of cast PMMA is 85 degrees Celsius (°C), about 10°C higher than extruded PMMA.

Chemical resistance

Owing to its higher molecular weight, cast PMMA shows better chemical resistance.

PMMA absorbs about 1.2 percent (%) water in humid ambient air and about 2% when stored in water. That means a one-meter-long (m) sheet of PMMA expands by about 1 to 2 mm, depending on how it is stored. The increase in volume due to water absorption is taken into account in the recommended expansion allowance of about 5 mm/m sheet length for PMMA.

Typically PMMA manufacturers guarantee their products for several years against yellowing and retaining high light transmission. Where can further information on the material be obtained? Further information on PMMA products can be found on individual manufacturer’s websites. Links to these websites can be found on our About Us page.

PMMA products can typically be purchased from plastic retailers and fabricators. Details are often listed on manufacturers’ websites. Commonly, bulk volumes can be purchased direct from the manufacturer.

PMMA is sold under many different trademarks, refer to manufacturers websites. What are the differences between PMMA and other plastic materials that appear very similar?

PMMA is the most beautiful plastic with a very good mechanical and UV stability. The machining is easy. Furthermore the flexibility of the production process allow us to produce a wide range of colour and specific properties in small volumes (impact, food contact, easy forming, surface effect, etc.).

The main applications of PMMA are visual communication, sanitary industry, automotive industry, architecture, POP/POS. Click here to discover the wide range of PMMA applications.

The PMMA benefits are the unmet UV and mechanical stability, good chemical and antiscratch characteristics and the optical properties (light transmission, no distortion,…). As the machining of the PMMA is easy and the process really flexible, the only limit is your imagination.

Unlike many other plastics, PMMA can be readily recycled all the way back to the original raw material (Methyl Methacrylate) which can be reused with almost no impact on quality.

Mechanical recycling means that parts made from PMMA can be ground and repelletised after correct separation, and reintroduce into the processing cycle. Since the recycling process leaves the original properties of PMMA more or less intact, the products manufactured from recycled material are of the same high quality as the original ones.

Chemical recycling is a process in which PMMA is reduced to its original monomer unit of methyl methacrylate, from which new PMMA or methacrylate dispersions/emulsions, for example, are built.

Both chemical and mechanical recycling are ways of obtaining high-quality material again from a high-quality product. Naturally, the optical appearance may suffer from impurities introduced during reprocessing.

In thermal recycling – if correctly incinerated – PMMA only gives rise to water (H2O) and carbon dioxide (CO2), i.e. no pollutant emissions. From this point of view, it is even superior to fossil fuels, which contain sulphur etc.

For further information, please contact manufacturers.

Owing to its properties, PMMA is primarily intended for the manufacture of durable, high-quality articles and less so for products meant to be consumed and disposed of within a short time. Thanks to its resistance to aging and weathering, PMMA remains fully functional even after many years of service, and does not need to be replaced at an early stage. Given correct fabrication, PMMA releases no pollutant substances to the environment. At the end of its product life and after careful separation from other materials, PMMA can be used for energy recovery and chemical or mechanical recycling.

PMMA scrap is not classed as hazardous waste. Small quantities can, therefore, be disposed of as household refuse. However, large quantities should be recycled.

If correctly processed, PMMA releases no harmful substances to the environment. The basic grades consist of the elements carbon, hydrogen and oxygen. Some grades can be employed in food-contact applications and the medical sector.

No, as compared with many other plastics, and especially with several types of wood and other natural materials, PMMA develops almost no smoke. Typically PMMA products will comply with the Euro Class E, which confirms the low smoke levels of acrylic materials.

No, the smoke gases emitted by PMMA were examined in detail by a specialized institute. The combustion gases generated by PMMAs are typically toxicologically inoffensive according to EN 50267-2-2 and do not impede escape from fire.

PMMA burns with a bright flame, virtually without smoke. Under normal circumstances, combustion only gives rise to carbon dioxide and water. Due to the material’s chemical composition (carbon, hydrogen and oxygen), no acutely toxic substances like phosgene, acid vapors and sulfur dioxide can form, even in a real fire. Since the material does not contain any halogens, no dioxins can form either.

No, the combustion gases generated by PMMA do no attack the surfaces of other materials.

No, PMMA contains no bisphenol A, nor does bisphenol A form during burning.

No, fire departments can use conventional fire-fighting agents. PMMA can be extinguished with water or any other extinguishing agent. Small fires can usually be blown out! The material cannot auto-ignite once the fire has been completely extinguished. Burning PMMA gives rise to no burning sparks whatsoever.

That depends on the individual plastic. Plastics like polyester, polycarbonate, plasticized and rigid PVC, polystyrene, polyolefin etc. sometimes form much greater quantities of smoke during combustion. Some of them may generate dangerous combustion gases.