What Is PETG and How Does It Differ from Standard PET?
PETG stands for glycol-modified polyethylene terephthalate — standard PET resin modified with a co-monomer (CHDM) that disrupts crystallization, producing an amorphous material with optical clarity, improved impact resistance, and significantly lower forming temperatures.
The result is a material visually similar to acrylic in transparency but meaningfully tougher in impact resistance and more forgiving in fabrication. PETG doesn't shatter like acrylic and thermoforms at lower temperatures than polycarbonate.
Key Properties of PETG Sheet
Optical clarity: ~90% light transmission in clear grades — suitable for display, glazing, and inspection windows.
Impact resistance: Significantly tougher than acrylic. Bends and deforms before fracturing — safer without polycarbonate's cost premium.
Thermoformability: Forms at lower temperatures over a wider window than acrylic or polycarbonate, with lower internal stress in formed parts.
Chemical resistance: Resistant to dilute acids, alkalis, and aqueous solutions. Better than acrylic against certain alcohols and cleaning agents.
Machinability: Machines cleanly, less prone to chipping than acrylic, generates less heat than polycarbonate.
FDA compliance: Meets FDA requirements for food contact in many applications.
Primary limitations: lower surface hardness than acrylic (scratches more easily, edges can't be flame-polished) and lower UV stability. For outdoor applications, UV-stabilized grades or protective coatings are necessary.
How Does PETG Compare to Acrylic and Polycarbonate?
Optical clarity (92% vs 90%), surface hardness, scratch resistance, UV stability, edge polishing capability. Best for display, signage, and outdoor applications.
Impact resistance (~30x tougher than acrylic, significantly stronger than PETG). Best for machine guards, safety glazing, ballistic applications.
Better impact than acrylic without polycarbonate's cost. Better surface than polycarbonate. Easier to fabricate than both. Best when appearance AND moderate impact matter on a budget.
PETG's wide forming window and low temperature make it preferred for vacuum-formed enclosures, covers, and trays where complex shapes are required.
What Is PETG Used For?
Retail displays: Clear enclosures and product cases where optical clarity is important and PETG's impact resistance reduces breakage during handling.
Thermoformed enclosures: PETG's wide forming window makes it preferred for vacuum-formed equipment covers and formed display components.
Food service: Sneeze guards, food display cases, and food processing covers where FDA compliance, clarity, and ease of cleaning are all required.
Medical: Instrument trays, equipment housings, and protective covers where clarity, chemical resistance to hospital cleaning agents, and moderate impact resistance are all relevant.
Frequently Asked Questions
Is PETG clearer than acrylic?
No — acrylic transmits 92% vs ~90% for PETG, and acrylic has a harder surface that polishes to better optical clarity. For maximum optical performance, acrylic is stronger. PETG offers comparable clarity for most practical display applications while providing better impact resistance.
How does PETG compare to polycarbonate for impact?
Polycarbonate is significantly more impact-resistant — roughly 30x tougher than acrylic and considerably stronger than PETG. For machine guards and high-energy impact scenarios, polycarbonate is correct. PETG is appropriate for moderate impact requirements where polycarbonate's full cost isn't justified.
Is PETG safe for food contact?
Yes — PETG meets FDA requirements for food contact in many applications. Widely used in food service display cases, sneeze guards, and food processing covers. Always confirm compliance for specific application and cleaning chemicals.
Can PETG be used outdoors?
Standard PETG has limited UV stability and will yellow under prolonged sunlight. For outdoor applications, acrylic is typically better due to inherent UV resistance. UV-stabilized PETG grades exist but are less widely stocked.
Where can I buy PETG sheet?
Plastic-Craft Products stocks PETG in clear and colored grades at their West Nyack, NY facility. No minimum orders. Call (845) 358-3010 or email [email protected].
Ready to Order PETG Sheet?
Plastic-Craft stocks PETG in a range of thicknesses and colors — cut to exact dimensions with no minimum orders. In-house CNC routing and thermoforming from a single experienced source.
(845) 358-3010