Insulation Type: Poly-X
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| With x = 12 the polymer is Poly (1,2,4,5-Benzenetetracarboxylic dianhydride-co-1,12-dodecanediamine) and x = 13 the polymer is Poly (1,2,4,5-Benzenetetracarboxylic dianhydride-co-1,13-tridecanediamine) |
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| Chemical Structure that closely shows the spatial arrangement of the atoms at minimum energy (x = 12)
Dark Gray = Carbon atoms
Light Gray = Hydrogen atoms
Blue = Nitrogen atoms
Red = Oxygen atoms
Yellow lines = Bonds to other monomer units in the polymer |
Aircraft on which Poly-X has been used/found- A-6 (No dates available)
- Boeing 747 (1970 - 1973)
- DC-10 (1968 - 1975)
- E-2 Hawkeye (No dates available)
- F-4 (No dates available)
- F-14 (No dates available)
- S-3 (No dates available)
- Lynx (No dates available)
*Note: Some of the older aircraft types of insulation may have replaced by the original wire. The listings of aircraft are not complete, especially with those special uses, e.g., engine areas, electronic boxes, etc.
Mil Specs and other Standards using Poly-X- MIL-W-81044/16
- MIL-W-81044/17
- MIL-W-81044/18
- MIL-W-81044/19
- MIL-W-81381/15
- MIL-W-81381/16
Advantages: Light Weight, 4.7 pounds/1000 feet (6.9 kg/km) for AWG 20 gauge wire
Nominal thickness –59 mils (1.50 mm) for AWG 20 gauge wire
High melting points, ~ 285 C for the 1,12 diamine and ~ 265 C for the 1,13 diamine
Disadvantages: Susceptible to solvents and hydrolysis especially at high pH
Extensive chafing problems reported
Difficult to control manufacturing process
Becomes brittle over time
Some types susceptible to arc tracking
Failed by radial cracking
Ages much more quickly than other insulation materials
Other Information: Military specification was withdrawn after a few years of introduction (all in the mid 1970s) for both MIL-W-81381/15 and /16 and MIL-W-81044/16 to /19
An antioxidant probably was added to the polymer as mentioned in Raychem patents
Cross linking by a high energy electron beam was mentioned in a Raychem patent
Most of the work in Raychem’s patents was with the 1,12 diamine
The top coating is a modified PMDA-ODA
Extent that this material has been removed from service is not known