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SynTherm® – Insulating Materials

SynTherm® AP/80

SynTherm® AP/80 is a flexible 2-layer insulation made of polyester film with calandered aramid paper overlay.


The proven dielectric properties of the polyester film and the excellent mechanical and thermal properties of the outer aramid paper layers result in a high performance insulating material. The ability of the outer layers to absorb impregnants results in exceptional bonding between all winding components.


SynTherm® AP/80 is a cost-effective insulating material used in electric motors as slot insulation, phase insulation and wedges.
SynTherm® AP/80 is used as core, interlayer und final insulation for transformers.

  • Suitable for class F (155 °C) systems.
  • UL approved e.g. E247773
  • RoHS compliant according to 2011/65/EU
Delivery forms

Total thickness in µm: 270
Other thicknesses on request

SynTherm® AP/80 is available:

  • in tapes:  depending on material thickness on request beginning at 6mm (thin material)
  • in rolls:    968 mm


  • Depth approx. 1 - 12 mm; distance approx. 1 - 10 mm
  • From widths of 10 mm to 240 mm, thickness on request

PET-film + aramid paper

Technical data
Typical mechanical properties
Nominal thickness  Typical thickness  Film thickness  Aramid paper thickness  Specific weight  Tensile strength longitudinal  Tensile strength transversal 
Unit of measure Values 
mm  0.27
mm  0.27±15 %
µm  190
µm  80
g/m²  335
N/cm  280
N/cm  330
Typical electrical properties
Nominal thickness  Dielectric strength 
Unit of measure Values 
mm  0.27
kV  24

SynTherm® is a registered trademark of SynFlex.