PET / Mylar Film, Rigid PET Sheet & PETG Sheet

Polyester (PET / PETG)

Polyester (PET) film is one of the most versatile electrical insulation materials we stock, offering excellent dielectric strength, clarity, and flexibility across an exceptionally wide temperature range. Our range covers thin flexible Mylar-type films for slot insulation and phase barriers through to rigid polyester sheet for structural insulation panels. Including perforated grades for ventilated insulation systems.

At a Glance

Temperature Range

-70 °C to +150 °C continuous

Thickness Range

0.025 mm to 3.2 mm

Brands We Stock

DuPont (Mylar)Toray
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Technical Properties

Typical values across stocked grades. Specific grade data sheets available on request.

Material TypePolyethylene terephthalate (PET) film and rigid sheet
AppearanceClear / translucent, flexible to rigid
Temperature ClassClass B (130 °C) to Class F (155 °C) per IEC 60085
Dielectric Strength≥ 150 kV/mm thin film; ≥ 40 kV/mm rigid sheet (ASTM D149)
Volume Resistivity≥ 10¹⁸ Ω·cm (ASTM D257)
Tensile Strength170–230 MPa (ASTM D882)
Density1.39–1.40 g/cm³
Water Absorption≤ 0.50 % (24 h immersion, ASTM D570)
Shrinkage≤ 1.5 % at 150 °C / 30 min (machine direction)
Tracking Resistance (CTI)≥ 600 V (IEC 60112)
FlammabilityUL 94 VTM-0 (thin film)
Thickness Range Stocked0.025 mm to 3.2 mm

Common Applications

  • Motor slot insulation and slot liners
  • Phase barriers and turn insulation
  • Transformer interlayer insulation
  • Flexible printed circuit substrates
  • Capacitor dielectric film
  • Cable wrapping and harness insulation
  • Electrical label and overlay substrates
  • Ventilated insulation systems (perforated grades)
  • General-purpose electrical isolation films
  • Coil and winding insulation

Available Grades

Brands we stock: DuPont (Mylar), Toray

Standard PET Film (Mylar Type)

Clear, flexible polyester film with outstanding dielectric strength and excellent mechanical properties. Our highest-volume polyester insulation product, available from 0.025 mm to 0.35 mm for slot insulation, phase barriers, and general-purpose electrical isolation.

Rigid Polyester Sheet

Thicker polyester sheet from 0.5 mm to 3.2 mm for structural insulation panels, terminal board substrates, and applications requiring greater mechanical rigidity. Retains the excellent dielectric and chemical resistance of PET film in a self-supporting format.

Perforated Polyester Film (Prd Grades)

Polyester film with precision-punched perforations for ventilated insulation systems. Allows air circulation through slot insulation for improved thermal management in motors and generators while maintaining adequate dielectric separation.

PETG Sheet

Amorphous glycol-modified polyester copolymer with improved impact resistance and thermoformability over standard PET. Optically clear, easy to fabricate by bending, forming, and cementing. Used for machine guards, display covers, food-contact packaging, and protective enclosures where clarity, toughness, and chemical resistance are all needed.

Related Resources

Chemical Compatibility

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Need Polyester (PET / PETG)?

We supply polyester (pet / petg) in sheet, roll, and custom die-cut forms. Contact our team for pricing, data sheets, or technical assistance.

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Disclaimer

This resource is provided for general engineering reference only and does not constitute professional advice, specification, or guarantee of performance. Actual results depend on specific application conditions. Universal Gaskets Pty Ltd accepts no responsibility or liability for decisions made based on this information. For full terms, see our Terms & Conditions.