Still the Gold Standard
By Donald M. Garcia, Director,
Research & Development, Boyd
Coatings Research Company Inc.
PTFE coatings are highly popu- lar in a vast variety of industries and in a myriad of applications.
Recently, PTFE has garnered much
attention due to recent changes put
forth by federal EPA protocols as well
as some unfortunate medical product recalls. However, when applied by coaters
with proper care and know-how, PTFE
still emerges as the best coating in terms
of low coefficient of friction.
PTFE (polytetrafluoroethylene) is a
fluorocarbon-based polymer proven to
be an essential coating that is used in
virtually all industries. Best-known for
its non-stick qualities, it can be used on
a vast array of materials such as carbon
steel, stainless steel, steel alloys, aluminum, brass, and magnesium, as well as
non-metallic surfaces such as glass and
some rubber materials. Additionally,
a newly-developed process to apply
unmodified PTFE to Nitinol without
adversely affecting the properties of the
underlying material has expanded the
range for the popular coating.
PTFE coatings are part of a family of
fluoropolymers, materials that are highly
desirable because they can provide a
low coefficient of friction or slipperiness.
They also offer corrosion, chemical, and
heat resistance; dielectric stability; chemical inertness to the surface of base materials; and “low/no-stick” properties for
easy release. In addition, PTFE coatings,
along with some other fluoropolymers,
PTFE can be combined with plastics,
resins, or other materials to modi-
fy existing characteristics, imparting
other specific and unique properties to
enhance compliance to user’s product
needs, especially for advanced technolo-
gies. Such properties commonly include
hydrophobicity, special coloration,
hardness, thermal or electrical insulation,
and conductivity. The exact combination
of PTFE with other materials is driven
by the client’s particular application.
For medical devices, PTFE is commonly used to coat surgical instruments
as well as medical components, guidewires, devices, and implantables.
EPA Promotes Elimination of PFOA
from PTFE Coatings
PFOA (Perfluorooctanoic acid) is a
chemical substance that was used in
the manufacture of PTFE (as well as hun-
dreds of other manufacturing and indus-
trial applications). After testing showed
that PFOA, a non-natural occurring
substance, was showing up persistently
at very low levels in the environment,
the EPA began investigations into the
chemical, and, ultimately, issued a request
to completely eliminate PFOA by 2015.
In the case of PTFE, some of the
PFOA used for manufacturing remained.
That meant that all U.S. companies would
have to develop new formulations of
products that would not utilize PFOA in
the manufacturing process. EPA had set
up the transition into two phases: the first
was a 95% reduction, which was completed in 2010, and the second to be completed by 2015. (It should be noted that while
the industry refers to the current materials
as Zero PFOA PTFE for convenience,
there is still the possibility of “trace” quantities of PFOA. The proper technical term
is “manufactured free of PFOA.”)
Since modification of coatings used on
medical components is more demanding
due to the paperwork and FDA requalification procedures on customers’ newly
altered devices, enlightened companies
began to reformulate their PTFE coatings
and transition customers over early on in
the game. Boyd Coatings ( www.boydcoatings.com), for example, developed its
Due to the limited availability of colors of industry supplied PTFE coatings, Boyd has
available additional standard and custom formulated colors made under controlled
conditions in its ISO9001 certified facility.