Cleveland, Ohio 44135 and. Bengi Hanyaloglu and Earl E. Graham. Cleveland State University. Cleveland, Ohio 44115 ... at a hot surface. (metal or ceramic).
NASA
Technical
Memorandum
106423
_. z)., ; Infrared Analysis Tricresylphosphate
Wilfredo Lewis
of Vapor Phase Deposited (TCP)
Morales
Research
Cleveland,
Center
Ohio
and Bengi
Hanyaloglu
Cleveland Cleveland,
January
and Earl
E. Graham
State University Ohio
1994
(NASA-TM-IO6423) OF
VAPOR
PHASE
TRIfiRESYLPHOSPHATE 20
INFRARED
N94-23371
ANALYSIS
DEPOSITED (TCP)
(NASA)
Unclas
p
G312T
0203585
(
Infrared
Analysis
of Vapor
Phase
Deposited
Tricresylphosphate
(TCP)
Wilfredo Morales National Aeronautics and Space Administration Lewis Research Center Cleveland, Ohio 44135 and Bengi Hanyaloglu and Earl E. Graham Cleveland State University Cleveland, Ohio 44115
Abstract Infrared
transmission
on two
different
vapors
and
of the
employed
substrates
collected
infrared
formation
was
data
to study
at 700°C.
onto
a NaC1
The
that a metal
of organophosphorus
polymeric
formation
deposit
substrate
suggests
the
and
was
of a lubricating
formed
on an iron
phosphate
from
coated
is formed
film
deposited
tricresylphosphate
NaC1
substrate.
Analysis
initially,
followed
by the
additive
in base
oils since
compounds.
Introduction Tricresylphosphate the
early
1900s.
It has
from
the formation
used
in several
temperatures where
highly
been
studies
lubricious.
group
of 400°C
(2-4).
a period
of time.
as an antiwear antiwear
on a wearing
the vapor
at a hot surface
used
(1) that the
involving
is directed
over
has been
concluded
of a phosphate
in excess
the gas
hot surface
(TCP)
phase
In these (metal
In many
cases,
surface.
lubrication studies
effectiveness
TCP
or ceramic). the resulting
of TCP
Recently,
TCP
of engineering is vaporized A deposit deposit
results
has been
surfaces
at
into a carrier is formed was
found
gas
on the to be
Analysis SEM
of the resulting
deposit
that
exists
to suggest
postulated Fe2Cs,
that
and
the
deposit
FePO4.
characterize
more
the deposit
consisted
In this present fully
has been
as a polymer.
of a bottom study,
the nature
attempted.
In a different
layer
infrared
Graham
and
Klaus
(2) used
study,
Klaus
et al. (5)
of Fe3C and a top layer
analysis
of the
deposit
was
of Fe2P, performed
to
of the deposit.
Experimental The
equipment
is basically stream
an oven
is directed
liquid
TCP
TCP
coated The
Two
with
used
in infrared
substrates
vapor
maintained
study
was
for 5 minutes,
vapor
stream
for
transform
10 minutes.
A transmission infrared
unit.
and the
conducted
for 1 minute.
stream
gas
temperature.
used:
other
is a NaC1
Figure
1 shows
stream
Using
gas at a constant
were
Graham
rate
one
was
(4). and
a syringe
the gas pump,
of 1.6 ml/hr.
The
flowing
at a rate
a plain
NaC1
window
that
the dimensions
It
of
window
had been
of the
substrate.
at 700 °C.
then
vapor
substrates.
studies,
and
% in the N 2 gas stream
substrates
800 * of iron.
were
stream
N 2 carrier
by Makld
into a carrier
at a known
at 1 mole
stationary
described
is vaporized
substrate
maintained
different
has been
TCP
into preheated
approximately
A time TCP
was
study
1) where
to a stationary
concentration
is typically
in this
(Figure
is introduced
200 ml/min. that
used
by first
exposing
NaC1
substrate
A second
and
finally
a third
This procedure infrared
analysis
NaC1 was
was
a plain was
substrate
then
repeated
then performed
NaC1
then was
substrate
exposed exposed
for the iron using
to the
to the to the
TCP
coated
a Nicolet
TCP
NaC1
fourier
Resultsand Discussion 1. Plain NaC1Substrate Figure 2 is the infrared (IR) spectrumof the 1 minutedeposit on a plain NaC1 substrate. Analysis of this spectrumsuggeststhat the depositmay be a sodium triphosphate compoundwith molecular formula NasP3010..In additionto the triphosphate,a small quantity of an organic compound(or compounds)having a P-O-Ar group may be present. Table 1 lists and comparesmany of the depositIR peakswith the known IR peaksof the triphosphate(6). Table 1 also lists the remainingIR peakswith the correspondinggroup absorptions. Although the 569 cm"1depositpeakcould not be adequatelyassigned,the presenceof a C1compoundis a possibility sincePC12absorbsin the 590 to 420 cmI range. KBr powder, containing the pure compoundNasP3010, waspressedinto a pellet and its FTIR spectrum(Figure 3) was taken. Comparisonbetweenfigures 2 and 3 shows agreementbetweennearly all the NasP3010 Figure Table
2 lists
compound to the
CH,
aromatic,
minute Peaks the 640
all the
peaks
(due
to the
4 is the
and
spectrum. 1294
peaks
where
apparent
1 minute
IR spectrum
cm "1 and
groups. have
of a deposit Many
groups.
Group
spectrum.
Analysis
cm 1, 1266
in three
all the IR peaks
P-O-Ar
deposit
of the 5 minute
present
formation
peaks.
suggests
cm _, 992
525 cm -i peaks
deposit Group
been
I lists
diminished
the
Group
II lists
of these
peaks
are more
3 lists
new
peaks
of P-H,
cm 1, and 693 cm "1 are not be assigned.
NaC1
peaks
assigned
triphosphate by other
peaks
corresponding
to
intense
that were P=O,
substrate.
sodium
or masked
film).
the presence
could
on a plain
P-O-P,
when
compared
not present and
P-O-Ar
to a pyrophosphate.
in the
1
groups. Only
The IR spectrumof the 10 minute deposit on the plain NaC1substrateis shown in Figure 5. Nearly all the IR peaksfrom the spectrumof the 5 minute deposit are presentin the spectrumof the 10 minute deposit. The only major difference in thesepeaksis that the 10 minute depositespectrumexhibits much strongerabsorptions(possibly due to the growth of the depositfilm). The major differencesbetweenthe 10 and 5 minute depositsare the appearanceof the broad peak at about2880 cm-1,andthe sharppeakat 771 cm1. The broad peak at 2880 cm P-O-Ar the
or P-O-C
severe
sodium
after
addition
of the
Iron-Coated
9 are different broke
down
C-H region,
NasP3010
is followed
deposit
to P-O-H difference
deposit.
NaC1 will
final
10 minute
to the P-O-Ar
One
used
the
The in the
(or compounds)
composition
and
overlap
triphosphate
compound
2.
absorption.
spectral
absorption
be attributed
"1 can
absorption between
prohibiting
These
results
and
the 5 and the
groups.
apparently
changes
to include
at 771
10 minute of any
that the
by the appearance
P-O-Ar
peak
detection
indicate
containing
the
initial
cm "1 to
deposits
is
C-H formation
of
of an organophosphorus
As time P-H,
progresses, P=O,
the
and
P-O-P
chemical groups
in
groups.
Substrate
notice
that
from
the legends
previous
and
format
IR spectra.
and this necessitated
of the
IR spectra
Unfortunately,
the use
of a different
shown
the FTIR FTIR
unit,
in Figures
unit that thus
was
6, 7, being
the different
formats. Figure substrate.
6 is the
These
peaks
IR spectrum
of the
are not as well
1 minute
defined
deposit
nor as sharp
4
formed
on the
as the IR peaks
Fe coated found
in the
plain NaC1substrates.This is most likely due to the reducedamountof IR radiation transmittedthrough the Fe coatedsubstrate. Analysis of this IR spectrumsuggeststhe presenceof iron phosphate,FePO4o2H20(6).Table 3 lists and comparesthe deposit IR peakswith the IR peaksof FePO4o2H20.In addition to the iron phosphatean organic phosphorousmaterial may be present. Table 3 also lists thesepeaks. Peaks2957 cm"1, 2911 cm_, and 2846 cm-1result from C-H absorptions. Peaks982 cm_ and 906 cm_ can also be attributedto P-O, P-O-C, or P-O-P absorptions(ref. 7). Peak 1034cm_ can be attributedto P-O-C absorption. was
pressed
figures
minute and
into a pellet
Figure
8 is the
IR spectrum
of the
shows
the presence
of four
1017
and Figure
Comparison
coated
iron
Peaks
1266
peaks
cm _ and from
absorption. appear
between
phosphate
cm I can result
C or P-O-Ar
stronger
The
The
new
7) was
peak
minute
pure
taken.
at 1266 detectable
Peak
peaks
at 2957
of the
ten minute
770
cm _, 2911
between
of FePO4*2H20.
Comparison
cm 1 can be attributed
absorption.
FePO4*2H20,
Comparison
assignments
deposit.
peaks:
compound
with
cm _, 1089 (due
the
cm _, 1017
cm "_,
to the formation
of a
to P=O
absorption
whereas
cm _ can be attributed cm _, and
one
2846
to P-O-
cm _ are
still
to be stronger.
9 is the IR spectrum with
(Figure
the major five
the
are no longer
1089
P-O-C C-H
containing
spectrum
agreement
film).
present
its FTIR
7 shows
770 cm _.
peak
powder,
6 and
deposit
deposit
and
KBr
the five
absorption
minute
of the peaks
These
results
NaC1
substrate.
indicate This
that
deposit at 1089
reveals
is followed
no new
cm "1, 1017
FePO4o2H20
deposit
on the
peaks.
cm I and the
is initially
by the appearance
formed
iron
The only doublet on the
of a possible
coated
substrate.
difference
is
at 770 cm -1. iron
(iron
oxide)
organophosphorus
compound(or compounds)having C-H, P-O-C, and possibleP-O-P groups. The deposit grows, covering
the
O-C,
groups.
and
P-O-P
suspected
iron phosphate
layer,
and now
may
consist
of C-H,
P=O,
P-
Conclusions Analysis on the
stationary
phosphate). formation could
of the
spectra
hot substrates
The and
infrared
metal
growth
be polymeric
is a metal
phosphate of possible
in nature;
indicates
thus,
that the
phosphate
apparently
then
(sodium serves
organophosphorus this work
supports
Klausl
6
initial
product triphosphate
as an "active"
compounds.
formed,
The
the suggestion
from
TCP,
or iron surface growth
made
for the of the
by Graham
deposit and
REFERENCES Wheeler,
.
D. R., Faut,
Tricresylphosphate (1984),
(TCP)
E.E.,
Klaus,
Temperatures," Vegas,
o
.
E. E.,
ASLE
Nevada,
and
and Gold,"
Thermal
Decomposition
Applications
of Surface
of
Science
18
"Lubrication
Preprint
No.
from
the Vapor
85-AM-1B-1,
Phase
at High
40th Annual
Meeting
in Las
Surfaces,"
Ph.D.
1985.
Makki,
J. F., "Vapor
Thesis,
Cleveland
Makki,
J., and
High
on Iron
Adsorption
p. 106-122.
Graham,
,
O. D., "The
Phase
State
University
Graham,
Temperature
Lubrication
E. E.,
Surfaces,"
of High
Temperature
(1989).
"Formation
of Solid
Lubrication
Films
Engineering,
from
Vol.
the Vapor
47, No.
Phase
3, pp.
on
199-206
(1991). Klaus,
.
E. E., Phillips,
Formed
During
Carbide,"
.
Corbridge, Phosphorous
o
Socrates, 1980.
the
STLE
J., Lin, Deposition
Preprint
D. E. C., Lowe, Compounds," G., Infrared
S. C., Wu, N. L., and Duda, of Lubrication
Molecule
J. L.,
on Iron
"Structure and
of Films
Silicon
1-8 (1988). E. J., "The J. Chem.
Characteristic
Infrared
Soc., Group
Spectra
of Some
Inorganic
1954. Frequencies,
John
Wiley
and
Sons,
Ltd.,
Table 1 1 Minme Deposit,Plain NaC1 Peaks
Observed ~1656--->
(cm 1)
N___P__301oPeaks
1606
-1620w, 1265w
vb
1215
1215
s
1146
1149
vs
1095
1095
1031
1022w
990
989
909
912 s,b
s w
798vw,b 753m
754 733
731 w
712
708 s Structural
Peaks
Observed
(cm -1)
(cm "1)
Group
To Observed
Assignment Peaks
_3356vb
O-H
3055
C-H
2919
C-H
1606
Aromatic Aromatic
str str
1453
Aromatic
str
1407
Aromatic
str
1483
1378 782
P-O-At
618
A-O-At
569
PC12
8
(cm I)
Table 2 5 Minute Deposit,Plain NaC1
I
N__._P__sl01o Peaks
Diminished
(cm':)
~1656 1215 1152 1095 1031 9O9 782 733
II
Peaks
Observed
Structural Group Assignments To Observed Peaks (cm 1)
(cm 1)
_3400
OH
3053
C-H
2965
C-H
2919
C-H
2872
C-H
1606
Aromatic
1484
Aromatic
1454
Aromatic
1400
Aromatic
782
P-O-Ar
617
P-O-Ar Structural
III New
Peaks
Observed
(cm:)
Group Assignments For Observed Peaks
2371
P-H
1640
O-H
1294
P=O
1266
P=O
1125
PH, P=O
992
P-O, P-O-P P-O-Ar
753 693 640 525
P-O-P
(cm _)
Table 3 1 Minute Deposit on Fe CoatedSubstrate
Peaks
Observed ~3400
(cm 1)
FePO*2H20
b
Peaks
(cm l)
~3330 s,b 1600
1625
1385 1255vw 1102
1105
1064 1005
1068 1005 850
Peaks
Observed
(cm 1)
Structural Group Assignment To Observed Peaks (cm _)
2957 2911
C-H
2846 1184
C-H C-H
1034 P-O-C
982 9O6
10
P-O,
P-O-C,
P-O-P
P-O,
P-O-C,
P-O-P
_- Vent
\
Stainless _--Preheating
ven
steel tube
\
L__
|
oven T-section
\
//-"?2:i°g _ Stainless steel t
11
_,
;
J ,
I // L-Sample holder
Liquid lubricant
_--Deposition
I J
i
Glass
I
i i I
I I
I I I Vaporization _ I section
N2 tube
_P-N2
wool
tube 7mm
[_
_
NaCI
3mm
Substrate
Figure 1.--Apparatus for vapor phase lubrication of stationary samples.
1407 1483 100 782 518 80
1656
1378
1606 1031
I
3055
3356
754
569 909
,_1!
\
1095
0 4000
I 3500
I 3000
I 2500
I 2000
I
I
1750
1500
I 1250
I
I
I
1000
750
450
Wavenumbers, (cm -1) Figure 2.--Infrared spectrum of I minute deposit. TCP on plain NaCI substrate.
ll
0 0 tO
--
6
o_ a.
E
..9.=
I p U.
0 0 LO CO
__
I
I
I
I
_
I
I
I
o
o
CO
0 0 0 ¢,Q q_-
LO 0
c_
0
d d o J,ueoJed 'eoue_,3j tusueJ1
0
(-q
O
It)
¢O (O ¢,) I'--
_--cO
O ¢O
--
h-
o
o4
CO .Q --I IZ) l--
v-
c O_ O4 t-
o
O
E
--I
-- _
--I
o E
2 0
Q. _
C
o I O O
O CO
O (O
O _I"
_ue0Jed'e0ue_!tusueJ.L
__
I O
0 o
0 o 0
Transmittance,
percent
o
.b,O 0 0 0
I GO 01 0 0
I
I
X,_jI
--
"11
_
N
J.
_
e
"0
2 3
_
o__"O
-
og N
o
o ol ",J
r _o (0
o_ e-
-____==
0
0
0 CO
--
0
0 n
Z 0
-_. 0 U.
O O. "I3
-I
E
E 0
I
_c
! ID
E
I 0
,@
I 4
I 4
I
I
II
M
M
_
lueoJed 'eouel-l!tUSUmJ.
0 0 110
r-t
O LO
--
oo T #-
I--
.
--
Q.
E
(/) "10
.=
I l< =e ;3 O)
t°
o
Q
03
o 0 03
--
0
I ¢q C_
I
_11
I
I
I
I
qd"
u!.
_
