Note: Descriptions are shown in the official language in which they were submitted.
SPRAY POLYUREA ELASTOI~IERS WTT~i IMPROVED ABRASION RESISTANCE
(D#80, 885 -y)
BACRGROUND OF 'fiiE INVENTION
1. Field of the Invention
The present invention relates generally to spray
polyurea elastomers and, more specifically, to spray polyu~ea
elastomers which include chemically sized mineral particles,
thereby improving the abrasion resistance of the cured elas-
tomer.
2» Description of Background Art
Elastomer systems are commonly recognized as, among
other things, coating materials, with spray polyurea elastomer
systems being particularly useful when employed in this capa-
city. One of the considerations confronting the skilled
artisan is the abrasion resistance of the coating after it is
ultimately applied to a substrate. In accordance with the
present invention the abrasion resistance of a spray polyurea
elastomer is improved by incorporating chemically sized mineral
particles in 'the system as is discussed with particularity
hereinbelaw. '
'U. S. Patent No. 4,585,850 describes a reaction
injection molded (RIM) elastomer made by reacting, in a closed
mold, an amine terminated polyether of greater than 1500
average molecular weight, having greater than 50% of their
active hydrogens in the form of amine hydrogens; a chain
extender; flaked glass pretreated with an amino silane coupling
agent; and an aromatic polyisocyanate. The '850 patent
~ar~dgvol
CA 02034205 2002-03-12
75704-115
referred to above contains a discussion of other applications
and patents in the field: for example, U.S. Patent Nos.
4,474,900 and 4,507,090.
Similarly, U.S. Patent No. 4,716,193 describes a reac-
tive glass component employed in a reinforced reaction injec- -
tion molded elastomer. Iiowever,~since these patents relate to
RIM elasta~aers, patentees are not concerned with abrasion
resistance. Specifically, RIM articles are invariably formed
in a closed mold and, accordingly, the elastomeric material
used to fona the molded article becomes pressurized within the
mold as additional amounts of elastomer are introduced therein.
As a result, the density of the thus formed article is greater
at the locus of the surface or skin, relative to the density at
the locus of the core. The increased surface density of a RIM
article provides a characteristic resistance to abrasion. This
phenomenon is not exhibited by spray polyurea coatings,
inasmuch as the coating is sprayed onto a substrate,. i.e., an
open mold, and, accordingly, the pressure required to provide
the increased surface density is unavailable.
Furthenaore, since the article formed via RIM typi-
cally has a topcoat, the degree to which the RIM article
exhibits resistance to abrasion is even further enhanced.
U.S. Patent No. 3,979,364 describes the use of
aminated polyethers as hereinafter used as a component with a
polyol to make an elastomer. U.S. Patent No. 3,666,788 de-
scribes the use of cyanoalkylated~aminated polyethers in spray
systems. The '788 disclosure, in Column l, states that the
aminated polyethers as used hereinafter cannot be used in spray
coatings due to very rapid reaction rates with isocyanates.
U.S. Patent Nos. 4,379,729; 4,444,910 and 4,433,067
describe elastomers which are prepared using a high molecular
2
CA 02034205 2002-03-12
75704-115
weight amine terminated polyether, an aromatic diamine chain
extender and an aromatic polyisocyanate which may merely be a
polyisocyanate or a quasi-prepolymer prepared from a polyol
reacted with a polyisocyanate wherein some isocyanate groups
are still left unreacted:- Various patents have been applied
for and received using the basic combination recited'above as
well as various mold release agents and other additives, such
as catalysts and fillers, including glass fibers. For example,
see U.S. Patent No. 4,607,090.
Polyoxyalkylene polyamines, particularly JEFFAMINE~
T-403, D-400 and D-230, are described as chain extenders in
U.S. Patent No. 4,732,919: however, this patent relates to an
elastomer system to be used in a RIM application.
The publication "Silane Effects and Machine Process
ing in reinforced High Modulus RIM urethane Composites," by
E.G. Schwartz, et al., Journal of Elastomers and Plastics, vol.
11 (Oct. 1979), page 280, describes the use of silane treated
milled glass fibers in reinforced RIM composites.
The publication "Surface Modification for . RrIM
Urethanes," by Ed Galli, Plastics Compounding (Jan/Feb 1982)
describes silane treated glass fiber reinforcement of RRIM
urethanes.
United States Patent No. 5,118,728
describes spray polyurea elastomers which include roved
filler materials that are externally added. A method for
making those elastomers is also described.
Therefore, it is my understanding that a spray
polyurea elastomer system which includes chemically sized
filler materials incorporated directly in the elastomer and
3
5
which exhibits favorable resistance to abrasion, especially
when employed as a coating, has heretofore been unavaiiabhe.
SUMMARY OF INVENTION
Accordingly, the present invention relates to a spray
polyurea elastomer which comprises an (A) component and a (N)
component. The (A) component includes an isocyanate. Prefer-
ably, the isocyanate of component (A) includes a quasi-prepoly-
ZO mer of an isocyanate and a material selected from at least one
polyol, a high molecular weight polyoxyalkyleneamine or a
. combination of these materials. The (B) component includes (I)
an amine terminated polyoxyalkylene polyol, (2) a chain exten
der and (3) a chemically sized filler material employed in an
15 amount sufficient to make the elastomer substantially resistant
to abrasion.
The present invention also relates to a method for
making a spray polyurea elastamer coating which is substan-
20 tially resistant to abrasion. Specifically, the method of this
invention comprises directing a first and second reactive
stream into mutual contact with each other to effectuate a
mixing of the first and second reactive streams. The first
reactive stream includes an isocyanate and the second reactive
25 stream includes an amine terminated polyoxyalkylene polyol, a
chain extender and a chemically sized filler material. The
mixed first and second reactive streams are delivered onto a
substrate in a manner such that the substrate becomes coated
with the mixed first and second reactive streams. The mixture
30 of the first and second reactive streams is then permitted to
cure on the substrate to form the spray polyurea elastomer
coating. The chemically sized filler material is employed in
the elastomer in an amount sufficient to make the elastomer
coating substantially resistant to abrasion.
~5
pr\dgv01
4
Advantageously, in addition to exhibiting substantial
resistance to abrasion, the polyurea spray elastomer of the
present invention exhibits other favorable characteristics, such
as good thermal stability, tear resistance and flexural modules.
Also, the processing characteristics of the elastomer, such as
speed and flexibility, are improved.
Generally, the present method involves spraying onto a
substrate: specific substrates include, but are not limited to,
open molds to manufacture, among otrier things, bathtubs, shower
stalls, automotive parts, boat hulls and in other applications
where fiberglass resins, epoxies and polyesters are typically
being used.
DESCRIPTION O~'' THE PREFERRED LfiiBODIP~;IdTTS
The isocyanates employed in component (A) are those
known to one skilled in the art. Thus, for instance, they can
include aliphatic isocyanates of the type described in U.S. Patent
No. 4,748,192. Accordingly, they are typically aliphatic
diisocyanates, and, more particularly, are the trimexized or the
biuretic form of an aliphatic diisocyanate, such as hexamethylene
diisocyanate, or the b:ifunctional monomer of the tetraalkyl xylene
diisocyanate, such as the tetramethyl xylene diisocyanate.
Cyclohexane diisocyanate is also to be considered a preferred
aliphatic,isocyanate. Other useful aliphatic polyisocyanates are
described fn U.S. Patent No. 4,705,814. They include aliphatic
diisocyanates, far example, alkylene diisocyanates with 4 to l2
carbon atoms in the, alkylene radical, such as 1,12-dodecane
diisocyanate and 1,4-tetramethylene diisocyanate. Also described
axe cycloaliphatic diisocyanates, such as 1,3 and 1,4-cyclohexane
diisocyanate as well as any desired mixture of these isomers,
1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane
pr\dg'v01
~~~E~~~
(isophorone diisocyanate); 4,4'-,2,2'- and 2,4'-dicyclohexylmethane
diisocyanate as well as the corresponding isomer mixtures, and the
like.
A wide variety of aromatic polyisocyanates may be used
to form the elastomer of the present invention. Typical aromatic
polyisocyanates include p-phenylene diisocyanate, polymethylene
polyphenylisocyanate, 2,6-toluene diisocyanate, dianisidine
diisocyanate, bitolylene diisocyanate, naphthalene-1,4-diiso-
20 cyanate, bis(4-isocyanatophenyl)methane, bis(3-methyl-3-iso-
cyanatophenyl)methane, bis(3-methyl-4-isocyanatophenyl)methane,
and 4,4'-diphenylpropane diisocyanate.
Other aromatic polyisocyanates used in the practice of
the invention are methylene-bridged polyphenyl polyisocyanate
mixtures which have a functionality of from about 2 to about 4.
These latter isocyanate compounds are generally produced by the
phosgenation of corresponding methylene bridged polyphenyl
polyamines, which are conventionally produced by the reaction of
formaldehyde and primary aromatic amines, such as aniline, in the
presence of hydrochloric acid and/or other acidic catalysts.
Known processes for preparing polyamines and corresponding
methylene-bridged polyphenyl polyisocyanates therefrom are
described in the literature and in many patents, for example, U.S.
Patent NOS. 2,6$3,730; 2,950,263; 3,012,00$; 3,344,162 and
3,362,979.
Usually methlene-bridged polyphenyl polyisocyanate
mixtures contain about 20 to about 100 weight percent methylene
diphenyldiisocyanate isomers, with the remainder being polyme
thylene polyphenyl diisocyanates having higher functionalities and
higher molecular weights. Typical of these are polyphenyl
polyisocyanate mixtures containing about 20 to loo weight percent
diphenyldiisocyanate isomers, of which 20 to abowt 95 weight
pr\dgv01 6
percent thereof is the 4,4'-isomer with the remainder being
polymethylene polyphenyl polisocyanates of higher molecular weight
and funtionality that, have an average functionality of from about
2.1 to about 3.5. These isocyanate mixtures are known,
commercially available materials and can be prepared by the
process described in U.S. patent No. 3,362,979.
By far the most preferred aromatic polyisocyanate is
methylene bis(4-phenylisacyanate) or MDT. pure MDT, quasi--
1o prepolymers of MDT, modified pure MDT,, etc. are useful. Materials
of this 'type may be used to prepare suitable TtTM elastomers.
Since pure MDT is a solid and, thus, often inconvenient to use,
liquid products based on MDI or methylene bis(4-phenylisocyanate)
are used herein.,: U.S. patent No. 3,394,154 describes a liquid MDT
product. More generally, uretonimine modified pure MDT is
included also. This product is made by heating pure distilled MDT
in the presence of a catalyst. The liquid product is a mixture of
pure MDI and modified MDT and is represented as follows:
-
2 [OCN ~ CHa ~ -NCO
Cagalyst
OCt~~CFia~NnC~N -~ CHa~-NCO ~ COa
Carb~diizaid~
OC2d ~ CHa ~ ..~ ~c~N~CFia~ NCO
0°C°~ ~~-.C~Ha p~-.-N~'CO ,
Ureto~~nit~ixr~n
Examples of commercial materials of this type are Daw's ISONATE~
125M (pure MIDI) and ISONATE 143L ("liquid°' MDT). preferably the
amount of isocyanates used is the stoichiometric amount based on
all the ingredients in the formulation or greaater than the
stoichiometric amount.
pr\dgvol ,
of course, the term isocyanate also includes quas~.~-
prepolymers of isocyanates or polyisocyanates with active.hydrogen
containing materials. The active hydrogen containing materials
can include, but are not limited to, a polyol ar polyols, a high
molecular weight polyoxyalkyleneamine or combinations thereof.
The polyols include polyether polyols, polyester dials,
trials, tetrols, etc., having an equi'ralent weight of at least
about 500, and preferably at least about x.,000 up to about 3,000.
l0 Those polyether polyols based on trihydric initiators of about
4,000 molecular weight and above are especially preferred. The
polyethers may be prepared from ethylene oxide, propylene oxide,
butylene oxide or mixtures of propylene oxide, butylene oxide
and/or ethylene oxide. other high molecular weight polyols which
may be useful in this invention are polyesters of hydroxyl
terminated rubbers, e.g., hydroxyl terminated polybutadiene.
Hydroxyl terminated quasi-prepolymers of polyols and isocyanates
are also useful in this invention.
Especially preferred are amine terminated polyether
polyols, including primary and secondary amine terminated
polyether polyols of greater than 1,500 average molecular weight
having from about 2 to about 6 functionality, preferably from
about 2 to about 3, arid an amine equivalent weight of from about
'750 to about 4,000. Mixtures of amine terminated polyethers may
be used. Tn a preferred embodiment the amine terminated
polyethers have an average molecular weight of at least about
2,500. These materials may be made by various methods known in
the art.
The amine terminated polyether resins useful in this
invention, for example, are polyether rosins made from an
appropriate initiator to which lower alkylene oxides, such as
ethylene oxide, propylene oxide, butylene oxide or mixtures
thereof, axw added with the resulting hydroxyl terminated polyol
then being am:inated.
pr\dgvol
8
CA 02034205 2002-03-12
75704-115
When two or more oxides are used, they may be
present as random mixtures or as blocks of one or the other
polyether. In the amination step it is highly desirable
that the terminal hydroxyl groups in the polyol be
essentially all secondary hydroxyl groups for ease of
amination. Normally, the amination step does not completely
replace all of the hydroxyl groups. However, the majority
of hydroxyl groups are replaced by amine groups. Therefore,
in a preferred embodiment, the amine terminated polyether
resins useful in this invention have greater than 50 percent
of their active hydrogens in the form of amine hydrogens.
If ethylene oxide is used it is desirable to cap the
hydroxyl terminated polyol with a small amount of higher
alkylene oxide to ensure that the terminal hydroxyl groups
are essentially all secondary hydroxyl groups. The polyols
so prepared are then reductively aminated by known
techniques, for example, as described in U.S. Patent No.
3,654,370.
In the practice of this invention, a single high
molecular weight amine terminated polyol may be used. Also,
mixtures of high molecular weight amine terminated polyols,
such as mixtures of di- and trifunctional materials and/or
different molecular weight or different chemical composition
materials, may be used.
Also, high molecular weight amine terminated
polyethers or simply polyether amines are included within
the scope of my invention and may be used alone or in
combination with the aforestated polyols. The term high
molecular weight is intended to include polyether amines
having a molecular weight of at least about 2000.
Particularly preferred are the JEFFAMINE° series of
9
CA 02034205 2002-03-12
75704-115
polyether amines available from Texaco Chemical Company;
they include JEFFAMINE D-2000, JEFFAMINE D-4000, JEFFAMINE
T-3000 and JEFFAMINE T-5000.
9a
These polyether amines are described with particularity in Texaco
Chemical Company~s product brochure entitled THE JEFFAMTNE
POLYO~YALKYLENEAM:CNES.
The (B) component of the present spray polyurea
elastomer system includes an amine terminated polyoxyalkylene
polyol and a chain extender. The amine terminated polyoxyalkylene
palyol is preferably selected from diols or triols and, most
preferably, includes a blend of diols and/or triols. The
particular polyols, i.e., diols and/or triols, employed in
component (E) are the same as those described hereinabove in
connection with the quasi-prepolymer of component (A).
The chain extenders useful in this invention include,
for example, 1-methyl-3,5-diethyl-2,4-diaminobenzene, 1-methyl-3,5
diethyl-2,6-diaminobenzene (both of these materials are also
called diethyltoluene diamine or DETDA), 1,3,5-triethyl-
2,6-diaminobenzene, 3,5,3',5'-tetraethyl-4,4P-diaminodiphenyl-
methane arid the like. Particularly preferred aromatic diamine
chain extenders are 1-methyl-3,5-diethyl-2,4-diaminobenzene or a
mixture of this compound with 1-methyl-3,5-diethyl-2,6-diamino-
benzene. It is within the scope of this invention to include some
aliphatic chain extender materials as described in U.S. Patent
Nos. 4,246,363 and 4,269,945.
Other chain extenders included amine terminated chain
extenders which are generally described as low molecular weight
polyoxyalkylene polyamines containing terminal amine groups. One
particular chain extender is represented by the formula:
35
pr~dgvol
~~j~% ~~
GH3
CH2-(O-CH2-'CH~NH2
CH3
CH3-CH2_ _CHZ.~O_Cg2_~H~NI-I2
H3
H2.~0"CH2-~H,~-~.-NH2
wherein x+y+z has a value of about 5.3. The average amine
hydrogen equivalent weight is about 6'7 and the product is
commercially available from Texaco Chemical Company as JEFFAMI~1E
T-403.
Another related polyoxypropylene chain extender is
represented by the formula:
CH ~-i H H
H2N~E j ~ C'-O) x-~-~-NI-i2
H fI H ~3
wherein x has a value of about 5.6. This product has an average
amine hydrogen equivalent weight of about 100 and is commercially
available from Texaco Chemical Company as JEFFAMINE D-400. The
product having the same formula as above wherein x has an average
value of about 2.6 is useful. This product has an average amine
hydrogen equivalent weight of about 57.5 and is commercially
available from Texaco Chemical Company as JEFFAMINE D-230.
Other chain extenders will bt~ apparent to those skilled
in the art and the above recitation is not intended to be a
limitation on the invention claimed herein.
The chemically sized filler materials can be employed in
component (A) or (B), preferably they are employed in component
pr\dgv01 11
~;~ ~ r~ '~~ sb ~~ .~'
(B). These materials are preferably mineral particles, such as
calcium metasilicate, milled glass, flaked glass, mica and glass
spheres, which have been chemically sized by being subjected to
treatment with a sizing agent, Such as amino silanes and epoxy
silanes. The sizing agent can also be selected from amine
terminated titanate and zirconate coupling agents,which are
available from Kenrich Petrochemicals Inc., Sayonne, N.J. The
sizing agent functions to provide a chemical bond between the
spray polyurea elastomer and the filler materials. One
particularly preferred mineral particle is WaLLASTOKUP~ 1001.2, an
amino silane treated Wollastonite, available from NY00, a division
of oanadian Pacific (U. S.) Inc.
The chemically sized filler particles are generally
Z5 employed in an amount of about greater than 0 to about 25 weight
percent of the overall elastomer. Preferably, the filler
particles axe employed in an amount of about 5 to about 20 weight
percent.
Since the present invention relates to a s ra
p y polyurea
elastomer, the particle size of the filler is a significant
aspect. Generally, the filler materials must be small enough so
that they are permitted to pass through the orifice of the spray
apparatus. Therefore, filler partiches used in RIM applications
are t
ypically not well suited for use in the instant invention.
The size of the filler particles used herein can range from about
1/256 inch to about 1/32 inch, with the preferred size ranging
from about 1/128 inch to about 1/64 inch.
Optionally, the present spray polyurea elastomer can
include an internal mold release agent to facilitate the removal
of the cured elastomer from the open mold. While the release
agent, if employed, can be incorporated into the (A) or (B)
component, it is preferably incorporated in ttxe (B) component.
The internal mold release agents useful in the present invention
pr\dgv01 12
are kno~,rn to those skilled in the art; they include, but are not
limited to, zinc stearate, sodium oleate and silicone agents.
Advantageously, the (A) and (B) components react to form
the present elastomer system without the aid of a catalyst.
However, if desired, a catalyst can be used.
Catalysts such as tertiary amines or an organic tin
compound may suitably be a stannous or stannic compound, such as a
stannous salt of a carboxylic acid, a trialkyltin oxide, a dialkyl-
tin dihalide, a dialkyltin oxide, etc., wherein the organic groups
of the organic portion of the tin compound are hydrocarbon groups
containing from 1 to 8 carbon atoms. For example, dibutyltin
dilaurate, dibutyl~tin diacetate, diethyltin diacetate, dihexyltin
diacetate, di-2-ethylhexyltin oxide, dioctyltin dioxide, stannous
octoate, stannous oleate, etc., or a mixture thereof, may be used.
Tertiary amine catalysts include trialkylamines (e. g.,
trimethylamine, triethylamine); heterocyclic amines, such as
N-alkymorpholines (e. g., N-methylmorpholine, N-ethylmorpholine,
dimethyldiaminodiethylether, etc.), 1,4-dimethylpiperazine, trie-
thylenediamine, etc.; and aliphatic polyamines, such as N,N,N'N~--
tetramethyl-2,3-butanediamine.
z5 Other conventional fomulation ingredients may be
employed in component (A) or (B) as needed, such as, for example,
foam stabilizers, also known as silicone oils or emulsifiers. The
foam stabilizers may be an organic silane or si7.oxane, For
example, compounds may be used having the formula:
RSi(O-(RZSit~)n-(oxyalkylene)mR]3 ,
wherein R is an alkyl group containing from 7. to 4 carbon atoms; r1
pr\dgv01 13
is an integer of from 4 to g; m is an integer of from 20 to 40~
and the oxyalkylene groups are derived from propylene oxide and
ethylene oxide. See, for example, U.S. Patent Ho. 3,194,773.
Pigments, for example titanium dioxide, may be
incorporated in the elastomer system, preferably in the (B)
component, to impart color properties to the elastomer.
Post curing of the elastomer of the invention is
optional. Pvst curing will improve some elastomeric properties,
such as heat sag. Employment of post curing depends on the
desired properties of the end product.
The (A) component and (B) component of the present spray
polyurea elastomer system are combined or mixed under high pres-
sure; most preferably, they are impingement mixed directly in the
high pressure spray equipment, which is, for example, a GUSMER~
H-V proportioner fitted with a GUSMER Model GX-7 spray gun. Tn
particular, a first and second pressurized stream of components
and (B), respectively, are delivered from two separate chambers
of the proportioner and are impacted or impinged upon each other
at high ~relocity to effectuate an intimate mixing of wthe two
components and, thus, the formation of the elastomer system, which
is then coated onto the desired substrate via the spray gun.
In a preferred embodiment, the mixing module of the
GUSMER GX-7 spray gun is modified by installing carbide mixing ~.
chambers to avoid the potential for the deterioration of the
plastic chamber by the sized filler particles.
The volumetric ratio of the (A) component to the (B)
component is generally from about 30 to 70 percent to about 70 to
30 percent. Preferably, component (A) and component (B) are
employed in a 1:1 volumetric ratio.
pr\dgvol 14
~~ ~~r~N:a
GLO~SAR~' OF TERMS AND MATERIALS
TEXOX~ PPG-2000 - Polypropylene oxide of about 2000 molecular
weight; a product of Texaco Chemical
Company.
ISONATE~' 143 L - Carbadiimide modified liquid MDI; a product
of the Upjohn Company.
T~OE~ SF_5505 - A 5500 molecular weight palyether triol
containing approximately 80~ primary
hydroxide groups.
FOMREZ'~ EPD-28 - Polypropylene oxide block, ethylene oxide
capped polyol of about 4000 molecular weight;
a product of WTTCO Corp.
JEFFAMINE'~ T-5000 - Polypropylene oxide triamine of about 5000
molecular weight; a product of Texaco
Chemical Company.
JEFFAMINE~ T-3000 - Polypropylene oxide triamine of about 3000
molecular weight; a product of Texaco
Chemical Company.
JEFFAMINE~ D-4000 - Polypropylene oxide diamine of about 4000
molecular weight; a product of Texaco
Chemical Company.
JEFFAMINE~ D-2000 - Polypropylene oxide diamine of about 2000
molecular weight; a product of Texaco
Chemical Company.
JEFFAMINE~ T-403, D-400 and D-~30 are described with particularity
hereinabove.
pr.\dgv01 15
The following examples are provided to further
illustrate preferred embodiments of the present invention and
should not be construed as limiting the present invention in any
way.
In the examples, all spray work was performed with a
GUSMER H-v high pressure proportioner with a model OX-7 spray gun.
The elastomer systems were sprayed using a block temperature of
160°F on the (A) component side and 150°F on the (B) component
side, with a hose temperature of 160°F. The system output ranged
from 17.5 lbs/min to 22.5 lbs/min with a line pressure ranging
from 2500 to 3000 psig on the (A) compo;r~ent side and 2000 to 2500
psig on the (B) component side. Each of the elastomer systems
produced in the examples were mixed at an (A)a(B) volumetric ratio
of 1:1. The (B) component containing the filler material did not
require agitation as it would have in RIM mixing equipment.
EXAMPLE I
The (A) component of a spray polyurea elastomer was
prepared by combining 60 parts of ISONATE 143L and 40 parts of
T~IANOL SF-5505 to form a quasi-prepolymer. The (B) component was
prepared by combining 27.07 parts of JEFFAMINE T-5000, 18..05 parts
of JEFFAMINE D-4000, 12.41 parts of JEFFAMINE D-2000, 32.15 parts
of DETDA and 10.32 parts of wOLLASTOKUP 10012. The (A) and (B)
components were mixed in the high pressure spray equipment at an
(A):(B) weight ratio of 1.066. The resulting reinforced polymer
elastomer was sprayed onto a flat metal substrate coated with a
zinc stearate based external mold release agent and exhibited a
gel time of 1 » 8 seconds. As spraying proceeded, a change in the
systems pressure was noted, which was ascribed to the deterio
ration of the mixing orifices on the (B) component side of the
plastic mixing module by the sized mineral particles.
J5
pr\dgvol
16
Frl
~~~~~~~~a
COMPARATIVE EXAMPLE I A
The (A) component of the spray polyurea elastomer
produced in this example was prepared in accordance with Example I.
The (B) component was prepared by combining 31.2 parts of
JEFFAMINE T-5000, 20.8 parts of JEFFAbIINE D-4000, 14,.3 parts of
JEFFAMINE D-2000 AND 33.7 parts of DETDA. The (A) and (B)
components were mixed in the high pressure spray equipment at an
(A):(B) weight ratio of 1.131. The polyurea elastomer produced in
this example was sprayed in accordance with Example I.
The physical properties of the polyurea elastomers
produced in Example I and Comparative Example I(A) were analyzeds
the results are reported in Table I.
TABLE T
Comparative
Example I Example I(A)
glass 4.61 0
Tensile (psi) 2058 2522
Elongation (o) 30 123
Tear (pli) 516 504
Shore D hardness (0 sec) 57 62
(10 sec) 52 5g
Flexural modulus (psi)
77F 70705 48118
158 F 42942 421'71
-20F 115088 110973
Impact, notched (ft.lbs/in) 3.44 9.15
Heat sag (mm)
100 mm - 250F/60 min 0 3.0
150 mm - 250F/60 min 4.0 15.0
100 mm 311F/60 min 4.0
150 mm - 311F/60 min 18.5 -
Abrasion resistance
280 550
(1000 gm, 1000 rev, H-18
wheels wt loss in mg)
pr\dgvUl 17
As these data demonstrate, the spray polyurea elastomer
of the present invention, which includes the chemically sized
filler materials (Example I), exhibits an abrasion resistance that
is nearly 100% better than an elastomer that is devoid of the
chemically sized particles (Comparative Example I(A)). These data
further establish other improved properties of the elastomer of
Example I relative to those exhibited by the elastomer of
Comparative Example I(A), such properties include tear resistance,
flexural modulus and high temperature properties.
EXAMPLE II
The (A) component of a spray polyurea elastomer was
prepared by combining 50 parts of ISONATE 143L and 50 parts of
FOMREZ EPD-28. The (B) component was prepared by combining 39.7
parts of JEFFAMINE T-5000, 24.8 parts of JEFFAMINE D-2000, 23.8
parts of DETDA, 1.5 parts of zinc stearate and 10.2 parts of
WOLLASTOKUP 10012. The (A) and (B) components were mixed in the
high pressure spray equipment at an (A):(B) weight ratio of 1.032.
The resulting reinforced polyurea elastomer was sprayed onto
a flat metal substrate with no external mold release agent and
exhibited a gel time of 2.0 seconds. The spray gun was modified
to include carbide internal mixing components and, as a result, no
pressure deviation was experienced.
COMPA1ZATIVE EXAMPLE II la)
The (A) component of the spray polyurea elastomer
produced in this Example was prepared in accordance with Example
IT. The (B) component was prepared by combining 45.0 parts of
JEFFAMINE T-5000, 28.2 parts of JEFFAMINE D-2000, 25.3 parts of
DETDA arid 1.5 parts of zinc stearate. The (A) and (B) components
were mixed in the high pressure spray equipment at an (A):(B)
weight ratio of 1.107. The resulting polyurea elastomer was
sprayed onto the flat metal substrate as in Example II.
pr\dgvOl 18
4,~ e9 ~'~ ~ ,.
The physical properties of the polyurea elastomer
produced Example II and Comparative Example II(A) were analyzed;
the results are reported in Table II.
TAHLE TI
Comparative
Examtale z Example No.TIlA)
~ glass 4.76 0
Tensile (psi) 1895 1741
Elongation {~) 247 267
Tear (pli) 408 344
Flexural modul us (psi)
77F 26583 19581
158F 17912 13509
-20F 57273 44671
Impact, notche d (ft.lbs/in) 7.42 4.24
Heat sag (mm)
100 mm - 250F/60 min 3.0 4.0
150 mm - 250F/60 min 17.5 28.0
Abrasion resistance 290 520
(1000 gm, 1000 rev, H-18
wheels wt loss in mg)
As these data demonstrate, the spray polyurea elastomer~.
of the present invention, which includes the chemically sized
filler materials (Example II), exhibits an abrasion resistance
that is nearly 90% better than an elastomer that is devoid of the
chemically sized particles (Comparative Example II(A)). These
data further establish other improved properties of the present ,
elastomer, such as tear resistance, flexural modulus and high
temperature properties.
pr\dgv01 19
