Tech. Note 20 - Stabilants in Military Applications
General Information about Stabilant 22 in Military Applications
What is Stabilant 22?
Stabilant 22 is an initially non-conductive amorphous-semi-conductive
block polymer that when used in thin films within contacts acts under the
effect of the electric field and switches to a conductive state. The
electric field gradient at which this occurs is established during its
manufacture so that the material will remain non-conductive between
adjacent contacts in a multiple pin connector environment.
Thus, when applied to electromechanical contacts, Stabilant 22 provides
the connection reliability of a soldered joint without bonding the contacting
Chemically, Stabilant 22 is a polyoxyethylene-polyoxypropyline
block polymer with molecular weight of about 2800. It has a very low vapor
pressure and therefor there is no appreciable loss of material from evaporation.
It has been in some applications for more than fifteen years without renewal,
and it is probably safe to say that in the majority of cases, the equipment
on which it is used will be retired for obsolescence before the Stabilant
must be renewed. In its undiluted form at room temperature (Stabilant
22) it has the viscosity of a medium weight motor oil, a though it
thins out with increasing temperature, starting to decompose into the two
polymers it is formed from about 240 ° Celsius.
What is its use?
Stabilant 22 is used to increase the reliability of contacts.
Tenfold to one hundred fold increases are not unusual. At the present time
it is used in many different type of contacts, including card edge connectors,
D-Type connectors, MIL-spec connector signal switches etc.
The material can be used in manufacturing, in service facilities and
in the field.
Because of the ease of application, Stabilants allow service
personnel in the field to catch and correct those faults caused
by unreliable connector operation; making it unnecessary in many cases,
to return the equipment is for shop service. Thus, the amount of "float"
is significantly reduced.
It also permits the use of a shotgun approach. (i.e. treating all connectors
in a system as if they were faulty) In this way, many of the erratic and
often non reproducible faults typical of erratic connectors, can be corrected
by service personnel who are no expert diagnosticians. This can considerably
increase the speed of service as it reduces bottlenecks created by the
usual limited availability of diagnostic facilities of expert personnel.
Stabilant 22, Stabilant 22A, and Stabilant 22E are used
in electronics where equipment failure can cost lives; equipment such as
biomedical electronics in hospitals, as well as aircraft navigation and
instrument landing systems.
What is its service life?
Obviously there will be some loss of the material through attrition,
such as when connectors are unplugged; however, the Stabilant material
has a very low vapor pressure and thus, loss due to evaporation is virtually
nonexistent. Accelerants and curing agents that are frequently present
in thermoset plastics and rubber compounds do not cause cross linking or
"varnishing" of the Stabilants. Chemically, the Stabilants
a very low reactivity and will not affect the materials used in electronics.
Quite often, electronic systems treated with Stabilants are still
working by the time when they are replaced as obsolete while the non treated
equivalents have been retired as non serviceable. We have had reports of
otherwise unreliable equipment which has functioned perfectly for over
fifteen years after treatment.
The shelf life of the Stabilants (excluding alcohol evaporation
caused by loose caps in opened bottles of Stabilant 22A or Stabilant
22E) is well in excess of fifteen years.
In what forms are they available?
The Stabilants are packaged in 5 ml, 15 ml, 5O mL, lOO mL, 25O
mL and 5OO mL containers for both the Concentrate (Stabilant 22) and alcohol
diluted (Stabilant 22A) The concentrate is also supplied in 1 Liter bottled.
Please refer to the section "Sizes and Packaging" for the Stabilant 22E
Because of the 4:1 dilution of the diluted Stabilants, they will generally
cost about one fifth the amount of the concentrate, although, obviously,
it is the concentrate that does the job. The alcohol is just there as a
solvent to "carry" the concentrate into place, once its there the alcohol
evaporates. This version can be applied to socketed IC's without removing
them from the sockets. The concentrate on the other hand is often used
as an insertion aid when inserting multiple pin IC's because of its lubricating
Is Stabilant "just another contact cleaner"?
No, Stabilant 22 is an electrically active material which stays
within a contact pair, there enhancing conductivity without causing
electrical leakage between adjacent contacts. Thus large quantities of
the material do not have to be "hosed on" as is the case with cleaners.
While Stabilant 22 does have a detergent action it is not sold as
a cleaner, just as it has a good lubricant action but is not sold as a
Stabilants are often used to service older equipment and in many
cases, the use of the Stabilants to treat all of the system's connectors
is sufficient to restore non-functioning electronics to full operational
Just how much should be used?
Normally, a film thickness of about 0.5 to 1 mils of the concentrate
is more than enough. In other words, you want just enough to fill up the
minute gaps within the contacts. Where Stabilant 22A or Stabilant 22E
used, be sure to allow for the evaporation of the alcohol which forms 4/5th's
of the volume.
Both shop and field application of the material is simple. A small amount
is used to coat the pins of the connector. Because it does not short-out
between adjacent contacts over application need not be cleaned off the
connector body. There is a dropper tip on the 5 ml, the 15 mL and the 50
mL bottle of Stabilant 22A, which may be used. Or the material may be transferred
to a brush. On card edge connectors the material may be applied to one
end of the connector and fingertip wiped the length of the connector.
When treating socketed IC's, a "bead" of Stabilant 22A or Stabilant
22E should be run along the pin and allowed to "Wick" down into the
connector. In stubborn cases, the IC may have to be moved a small amount
to break the pin to socket contact seal on all pin Generally, pressing
firmly down on the IC to reset it will provide enough movement.
Because of the diagnostic difficulties of isolating connector related
fault condition the Stabilant materials are often used to treat
all the contacts in a system before more sophisticated diagnostic procedures
are run; under these circumstances we are told that in many instances,
no further repair work is necessary.
Is the material hazardous?
No, it has very low internal toxicity although ingestion should be
avoided. External no skin reactions have ever been observed The undiluted
form Stabilant 22 is of low flammability. In the United States Stabilants
are not subject to the Toxic Substance Control Act (TSCA) nor are they
reportable under SARA Title III
What is its Identification for Military procurement?
NATO/CAGE Supplier Code 38948
- 15 mL of Stabilant 22A (isopropanol diluted) has NATO Stock # 5999-21-900-6937
- 15 mL of Stabilant 22E (ethanol diluted) has NATO Stock # 5999-21-909-9984
- 15 mL of Stabilant 22 (non diluted) has NATO Stock # 5999-21-909-9981