If you’re standing in front of a project that needs a transparent plastic sheet and you’re not sure whether to buy acrylic, polycarbonate or PETG, you’re not alone. They look similar on the shelf. They’re all clear, all lighter than glass, all stronger than glass. But they behave differently in practice, and picking the wrong one can mean cracking, yellowing, melting or overspending.
Here’s how they actually compare not in lab conditions, but in the applications UK buyers use them for.
Optical Clarity
Acrylic wins. Clear acrylic transmits up to 92% of visible light more than standard glass and noticeably more than polycarbonate or PETG. It stays clear over years of UV exposure without yellowing. If your application demands crystal transparency display cases, picture glazing, retail fixtures, light panels acrylic is the obvious choice.
Polycarbonate has good clarity but tends to develop a slight yellow tint over time with UV exposure, particularly in outdoor applications. PETG sits between the two decent clarity with low haze, though not quite at acrylic’s level.
Impact Resistance
Polycarbonate wins by a wide margin. It’s virtually unbreakable. You can hit it with a hammer. This is the material used in riot shields, machine guards and bulletproof glazing. For any application where the sheet might take a serious impact safety glazing, vandal-prone locations, machine guarding, children’s play areas polycarbonate is the only serious option.
Acrylic is up to 17 times more impact-resistant than glass, which is impressive, but it will crack under a hard enough blow. It fractures into dull-edged pieces rather than dangerous shards, so it’s still far safer than glass just not in the same league as polycarbonate for raw toughness.
PETG is tougher than acrylic and won’t shatter or crack on impact. It deforms rather than fractures. It’s not as strong as polycarbonate, but for applications where you need something that won’t crack if dropped or knocked face shields, food guards, thermoformed components it’s a solid middle ground.
Heat Resistance
Polycarbonate wins again. It handles continuous use up to about 120°C and is self-extinguishing with a UK Class 1 fire rating. This matters for anything near heat sources behind cookers, near industrial equipment, in lighting housings.
Acrylic softens at around 80°C. It’s self-extinguishing but doesn’t carry the same fire rating as polycarbonate. Fine for most indoor and outdoor applications, but not suitable directly behind gas hobs or in high-temperature industrial environments.
PETG sits in the middle it handles slightly higher temperatures than acrylic and won’t crack in cold conditions where acrylic might become brittle. Its real thermal advantage is in thermoforming: PETG forms at lower temperatures than acrylic, making it more efficient and forgiving in vacuum forming and pressure forming applications.
Chemical Resistance
PETG wins. It resists a wide range of chemicals including acids, alkalis and most common cleaning agents. This is why it’s the default choice for food processing environments, pharmaceutical settings, cleanrooms and anywhere that requires regular chemical cleaning or sterilisation. It’s also FDA-compliant for direct food contact.
Acrylic is vulnerable to solvents alcohol, acetone and many household cleaning sprays will cause crazing (fine surface cracks). It handles mild cleaning agents fine but isn’t suited to environments with chemical exposure.
Polycarbonate has reasonable chemical resistance but is sensitive to some solvents and strong alkalis. It’s less chemically robust than PETG but more tolerant than acrylic.
Workability
Acrylic is the easiest to fabricate to a high finish. It cuts cleanly, drills predictably (with the right technique), and edges can be polished to a crystal-clear finish by sanding, buffing or flame polishing. It laser-cuts beautifully laser-cut edges come out flame-polished straight off the machine. It also bonds strongly with solvent cements for invisible joints.
Polycarbonate is harder to cut cleanly and can’t be flame-polished. Edge finishing is more limited. It can be cold-bent to tighter radii than acrylic without heating, which is useful for curved glazing. Drilling is straightforward but it’s more prone to burring.
PETG machines well and thermoforms at lower temperatures than acrylic. It doesn’t crack during drilling and handles bending better than acrylic. It’s the preferred material for vacuum-formed parts and thermoformed packaging.
UV and Weather Resistance
Acrylic is the outdoor champion. It resists UV degradation better than polycarbonate or PETG, maintaining clarity and colour stability for years in direct sunlight. This is why it’s the standard material for outdoor signage, architectural glazing and any application with prolonged sun exposure.
Polycarbonate degrades under UV unless it has a specific UV-stabilised coating. Most quality polycarbonate sheet comes with UV protection on one or both faces, but the coating can wear over time in harsh conditions.
PETG has moderate UV resistance. It’s fine for short to medium-term outdoor use but will degrade faster than acrylic in prolonged direct sunlight.
Cost
PETG is generally the most affordable of the three. Acrylic sits in the middle. Polycarbonate tends to be the most expensive, reflecting its superior impact and fire performance.
That said, cost should follow application. Buying the cheapest material and having it fail is always more expensive than buying the right one.
Quick Decision Guide
Choose acrylic when: Optical clarity is the priority. Outdoor signage and displays. Splashbacks, glazing and architectural features. Laser-cut signage and fabrication. Any application where polished edges and visual quality matter most.
Choose polycarbonate when: Impact resistance is non-negotiable. Fire rating matters (Class 1 required). The material is near heat sources. Safety glazing, machine guards, vandal-resistant installations. Curved glazing that needs cold-bending.
Choose PETG when: Chemical resistance is required. Food contact compliance is needed. The component will be thermoformed or vacuum-formed. Budget is tight and the application doesn’t demand the optical clarity of acrylic or the impact resistance of polycarbonate.
Still not sure? Get in touch with the specifics of your project and the team can recommend the right material and thickness.