Microwave Fabrics
 Gore radome architectural enclosures are the only microwave enclosures that can be made portable and that will survive harsh chemical and extreme environmental conditions, while minimizing microwave transmission loss.
Gore membrane radome products are made from fluorocarbon resins, typically in the form of membrane laminated to a woven PTFE fiber fabric.
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A = Gore radome
Er = 1.55, tan X = 0.0005, 't' = 0.012 in
B = Teflon® Fiberglass
Er = 2.0, tan X = 0.0016, 't' = 0.028 in
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C = Esscolam 8
Er = 2.8, tan X = 0.0012, 't' = 0.012 in
D = Sumitomo Rubber
Er = 3.05, tan X = 0.0052, 't' = 0.031 in
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The graph above illustrates the performance of Gore radome laminate against comparable materials with respect to direct transmission loss in the microwave and millimeter wave region.
Tests were carried out by CSIRO, Sydney, Australia.
Weathering properties of PTFE-based materials
"15 years-zero failure"
"Parts fabricated of Teflon fluorocarbon resins are virtually unaffected by weather. Conclusive tests on samples exposed for 15 years to practically all climatic conditions confirm these weather-resistant properties. Thus, where applications demand the ultimate in dependability under these conditions, these resins are the answer. Resistance to extreme heat, cold and ultraviolet light encountered in radar and other electronic components (such as antenna bushings) are excellent examples of the value of this material to the industrial designer."
Abstracted from: Teflon Fluorocarbon Resin, Mechanical Design Data E. I. DuPont de Nemours & Co., Inc., Wilmington, DE
"30 Years-Zero Failure"
"The good weathering properties of PTFE are referred to in the basic paper on PTFE (Fluorine containing polymers Part II PTFE Fortschr. Hoch polymer-Forsch; Bd. 2, S. 456-495, 1961, Sperati and Starkweather) where it is stated that there is 'no detectable change after ten years of outdoor exposure in Florida'.
'Within our own laboratories, we have done tests in a 'weatherometer' on a PTFE composite in order to test the effect on the composite material-not the PTFE. The testing involved 8,000 hours of exposure to about 20 years of natural weathering. At the end of the trial, the PTFE component was unaffected, although the other material had started to weaken slightly; this confirms our experience of about 30 years in which we have had no adverse comments on the weathering properties of PTFE."
Abstracted from: Technical correspondence from C. G. Kinnear, 'Fluon' Technical Section, Imperial Chemical Industries PLC, to Dr. R. L. T. Street, Rutherford Appleton Lab May 25, 1983
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Fabric type: RA 7906
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Fabric color
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White
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Chemical constituent
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100% fluoropolymer
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Mullen burst (typical) ASTM D-3786
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4,500 kN/m2
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650 psi
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Weight (typical)
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410 g/m2
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12 oz/yd2
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Breaking load (typical) - cross direction
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29 kN/m
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165 lb/in
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Breaking load (typical) - machine direction ASTM D-1682
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42 kN/m
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240 lb/in
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Nominal thickness
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0.28 mm
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0.011 in
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Air permeability
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0
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0
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