Spray polyurea elastomers containing organic carbonates to improve processing characteristics

Spray polyurea elastomers are disclosed made from an (A) component and a (B) component, where the (A) component has a quasi-prepolymer made from an isocyanate and an active hydrogen-containing material, such as a polyoxyalkylenepolyamine. The (B) component includes an amine resin, such as an amine-terminated polyoxyalkylene polyol which may be the same or different from the polyoxyalkylene polyamine of the quasi-prepolymer. The viscosity of the (A) component is reduced by the inclusion of an organic, alkylene carbonate, such as ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, and the like. The alkylene carbonate also serves as a compatibilizer between between the two components, thus giving an improved mix of the system.

FIELD OF THE INVENTION 
The invention relates to aliphatic and aromatic spray polyurea elastomers 
and processes for making the same, and, in one aspect, more particularly 
to methods for making aliphatic and aromatic spray polyurea elastomers 
containing organic carbonates. 
BACKGROUND OF THE INVENTION 
Spray elastomer systems are commonly recognized as coating materials, with 
aliphatic and aromatic spray polyurea elastomer systems being particularly 
useful when employed in this capacity. This two-component technology is 
based on an isocyanate quasi-prepolymer and an amine coreactant, often an 
amine resin blend. Typically, the isocyanate quasi-prepolymer is higher in 
viscosity than the amine resin blend. This difference in viscosity, 
coupled with the fast reaction characteristics of these systems, can lead 
to processing problems in thin film applications. 
For example, it would be desirable to provide a spray elastomer system 
where the viscosity of the isocyanate quasi-prepolymer could be lowered. 
Further, it would be advantageous if such a system would permit the two 
components to combine more readily to quickly provide a homogeneous 
mixture. 
There is considerable published literature on the topic of polyurea 
elastomers. For example, see U.S. Pat. No. 5,162,388 to Dudley J. 
Primeaux, II, which discusses aliphatic polyurea elastomers having an (A) 
component and a (B) component. The (A) component includes an aliphatic 
isocyanate, while the (B) component includes an amine-terminated 
polyoxyalkylene polyol and a chain extender. The chain extender may 
include cis-1,4-diaminocyclohexane, isophoronediamine, m-xylenediamine, 
4,4'-methylenedicyclohexylamine, methanediamine, 
1,4-diaminoethylcyclohexane and substituted derivatives thereof. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to provide an 
aliphatic and aromatic spray polyurea elastomer where the isocyanate 
quasi-prepolymer component has reduced viscosity from that known before. 
It is another object of the present invention to provide an aliphatic 
and/or aromatic spray polyurea elastomer where the agent that provides for 
reduced viscosity of the isocyanate component also acts as a 
compatibilizer between the two components to improve the mix of components 
and homogeneity of the system. 
A particular object of the invention is to provide an aliphatic and/or 
aromatic spray polyurea elastomer with the above characteristics and which 
has good physical properties including good surface characteristics. 
In carrying out these and other objects of the invention, there is 
provided, in one form, a spray polyurea elastomer having an (A) component 
which includes a quasi-prepolymer of an isocyanate and an active 
hydrogen-containing material; together with an alkylene carbonate. To make 
the elastomer, the (A) component is reacted with the (B) component which 
has at least one amine-terminated polyoxyalkylene polyol. In one 
embodiment of the invention, the (B) component is an amine resin blend.

DETAILED DESCRIPTION OF THE INVENTION 
It has been discovered that the addition of an organic, alkylene carbonate, 
such as TEXACAR.RTM. PC or TEXACAR EC-50, to the isocyanate 
quasi-prepolymer of the (A) component, will result in a lower viscosity 
component. The carbonate also functions as a compatibilizer between the 
two components, which gives an improved mix and increased homogeneity of 
the system. This lower viscosity and improved mix allows for paint-type 
application of the aliphatic and/or aromatic spray polyurea technology. 
The aliphatic and/or aromatic spray polyurea elastomer system of the 
present invention generally includes two components, an (A) component and 
a (B) component. In particular, the (A) component may include an aliphatic 
isocyanate. The aliphatic isocyanates employed in component (A) are those 
known to one skilled in the art. Thus, for instance, the aliphatic 
isocyanates are of the type described in U.S. Pat. No. 4,748,192, 
incorporated by reference herein. Accordingly, they are typically 
aliphatic diisocyanates, and more particularly are the trimerized or the 
biuretic form of an aliphatic diisocyanate, such as, hexamethylene 
diisocyanate, or the bifunctional 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 in U.S. Pat. No. 
4,705,814, also incorporated by reference herein. They include aliphatic 
diisocyanates, for example, alkylene diisocyanates with 4 to 12 carbon 
atoms in the alkylene radical, such as 1,12-dodecane diisocyanate and 
1,4-tetramethylene diisocyanate. Also described are 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-isocyanatomethylcyclohexane (isophorone 
diisocyanate); 4,4'-, 2,2'- and 2,4'-dicyclohexylmethane diisocyanate as 
well as the corresponding isomer mixtures, and the like. 
Aromatic isocyanates may also be employed. Suitable aromatic 
polyisocyanates include, but are not necessarily limited to, m-phenylene 
diisocyanate; p-phenylene diisocyanate; polymethylene 
polyphenylisocyanate; 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 
dianisidine diisocyanate; bitolylene diisocyanate; 
naphthalene-1,4-diisocyanate; diphenylene-4,4'-diisocyanate; and the like. 
Aliphatic/aromatic diisocyanates, such as xylylene-1,3-diisocyanate; 
bis(4-isocyanatophenyl)methane; bis(3-methyl-4-isocyanatophenyl)methane; 
and 4,4'-diphenylpropane diisocyanate. The aforestated isocyanates can be 
used alone or in combination. 
In the practice of the present invention, it is expected that the 
isocyanate will be at least partially reacted with an active 
hydrogen-containing material. The alkylene carbonates of this invention 
may be added to an (A) component having only a un-prereacted isocyanate 
therein, that is, not at least partially reacted with an active 
hydrogen-containing material to form a quasi-prepolymer. In such a case, 
the carbonates would work as a reactive diluent. However, it is 
anticipated that the alkylene carbonates will find a greater utility in 
the situation where the (A) component contains a quasi-prepolymer of a 
relatively high viscosity which may be lowered by the alkylene carbonate. 
The active hydrogen-containing materials may include, but are not 
necessarily limited to polyols or high molecular weight 
polyoxyalkyleneamines, also described herein as amine-terminated 
polyethers, or a combination thereof. 
The polyols include, but are not necessarily limited to, polyether polyols, 
polyester diols, triols, tetrols, etc., having an equivalent weight of at 
least about 500, and preferably at least about 1,000 up to about 3,000. 
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, and an amine equivalent 
weight of from about 750 to about 4,000. Mixtures of amine-terminated 
polyethers may be used. In 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 resins made from an appropriate initiator to which 
lower alkylene oxides, such as ethylene oxide, propylene oxide, butylene 
oxide or mixtures thereof, are added with the resulting 
hydroxyl-terminated polyol then being aminated. 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. Pat. No. 3,654,370, 
the contents of which are incorporated by reference herein. 
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.RTM. 
series of polyether amines available from Huntsman Corporation; they 
include JEFFAMINE D-2000, JEFFAMINE D-4000, JEFFAMINE T-3000 and JEFFAMINE 
T-5000. 
As noted, the (A) component of the present spray polyurea elastomer systems 
include an organic alkylene carbonate. The alkylene carbonate may have the 
structure (1): 
##STR1## 
where R.sup.1 and R.sup.2 are independently hydrogen or lower alkyl of 1 
to 4 carbon atoms. In a particular embodiment of the invention, the 
alkylene carbonates are preferably chosen from the group of ethylene 
carbonate, propylene carbonate, butylene carbonate and dimethyl carbonate. 
In one embodiment of the invention, the proportion of alkylene carbonate in 
(A) component ranges from about 1 to about 20 percent, preferably from 
about 5 to 15 percent and most preferably from about 5 to 10 percent. 
These percentages are based on 100 volume parts in the (A) component. The 
use of the alkylene carbonates reduces the viscosity of the (A) component, 
allows slower effective reactivities in spray polyurea elastomer systems, 
improved properties and surface characteristics (flowability) and possibly 
improved adhesion to the surfaces on which the elastomer is sprayed. The 
polyurea elastomers of the invention can be used as protective coatings, 
in "paint" applications, membranes, barrier coatings, road marking 
coatings, decorative coatings, automotive instrument panel applications, 
and the like. 
The polyurea elastomer systems may also include chain extenders in the 
formulation, preferably within the (B) component. Suitable chain extenders 
include those aliphatic and cycloaliphatic diamine chain extenders 
mentioned in U.S. Pat. No. 5,162,388 and patent application Ser. No. 
08/117,962, incorporated herein by reference. Aromatic diamine chain 
extenders may also be useful. 
Other conventional formulation 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 siloxane. For example, compounds may be used having the formula: 
EQU RSi[O-(R.sub.2 SiO).sub.n -(oxyalkylene).sub.m R].sub.3 
wherein R is an alkyl group containing from 1 to 4 carbon atoms; n is an 
integer of from 4 to 8; 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. Pat. No. 3,194,773, incorporated by reference 
herein. Pigments, for example titanium dioxide, may be incorporated in the 
elastomer system, preferably in the (B) component, to impart color 
properties to the elastomer. 
Reinforcing materials, if desired, useful in the practice of the invention 
are known to those skilled in the art. For example, chopped or milled 
glass fibers, chopped or milled carbon fibers and/or other mineral fibers 
are useful. 
Post curing of the elastomer of the invention is optional. Post 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 pressure; most preferably, they are 
impingement mixed directly in the high pressure spray equipment. In 
particular, a first and second pressurized stream of components (A) and 
(B), respectively, are delivered from two separate chambers of the 
proportioner and are impacted or impinged upon each other at high velocity 
to effectuate an intimate mixing of the two components and, thus, the 
formulation of the elastomer system, which is then coated onto the desired 
substrate via the spray gun. 
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. 
Advantageously, the (A) and (B) components react to form the present 
elastomer system without the aid of a catalyst. 
The following Examples are provided to further illustrate the preferred 
embodiments of the present invention, but should not be construed as 
limiting the present invention in any way. 
Spray Work 
For all the spray work described in these Examples, a GUSMER.RTM. VR-H-3000 
Proportioning unit (plural component) was used, fitted with a GUSMER 
GX-7-400 spray gun. The equipment was set so as to process each example at 
an isocyanate to resin blend volume ratio of 1.00. Spray processing 
pressures were maintained at 1500 psi to 2500 psi on both the isocyanate 
and resin blend components. Block heat, as well as hose heat, was set at 
160.degree. F. 
EXAMPLE I 
This spray polyurea application used a system with the A-Component, a 
quasi-prepolymer of m-TMXDI.RTM., 54.5 parts; and JEFFAMINE.RTM. D-2000, 
36.4 parts. To this quasi-prepolymer, 9.1 parts of TEXACAR.RTM. PC 
(propylene carbonate) was added, all collectively referred to as the 
isocyanate component. The isocyanate component was reacted with a 
B-component (amine resin blend), a blend of JEFFAMINE T-5000, 24.9 parts; 
JEFFAMINE D-2000, 24.9 parts; JEFFAMINE T-403, 18.7 parts; JEFFAMINE 
D-230, 27.4 parts; and TiPure.RTM. R-900 (titanium dioxide), 4.1 parts. 
These components were mixed at a volume ratio of 1.00 (1.00 weight ratio) 
with high pressure, high temperature impingement mix spray equipment. The 
resulting aliphatic polyurea elastomer had an effective gel time of 2.0 
seconds with a tack free time of approximately 10 seconds. Formulation and 
elastomer physical properties are detailed in Table I. This system was 
easily applied to a metal substrate with a uniform elastomer film 
thickness of 5 mils (0.005 inches). 
EXAMPLE II 
This Example used a system with the same A-Component (isocyanate 
quasi-prepolymer component) as mentioned in Example I. The B-component 
used was a blend of JEFFAMINE T-5000, 22.8 parts; JEFFAMINE D-2000, 22.8 
parts; JEFFAMINE T-403, 17.1 parts; JEFFAMINE D-230, 27.4 parts; and 
TiPure.RTM. R-900, 9.9 parts. These components were mixed at a volume 
ratio of 1.00 (1.00 weight ratio) using the same spray equipment in 
Example I. The resulting aliphatic polyurea elastomer had an effective gel 
time of 2.0 seconds with a tack free time of approximately 10 seconds. 
Formulation and elastomer physical properties are detailed in Table I. 
This system was easily applied to a metal substrate with a uniform 
elastomer film thickness of 5 mils (0.005 inches). 
COMATIVE EXAMPLE III 
For comparison, this Example used a system with an A-Component (isocyanate 
quasi-prepolymer component) of composition: a quasi-prepolymer of m-TMXDI, 
55 parts; and JEFFAMINE D-2000, 45 parts, with no alkylene carbonate. The 
B-component used was a blend of JEFFAMINE T-5000, 19.25 parts; JEFFAMINE 
D-2000, 28.87 parts; JEFFAMINE T-403, 22.86 parts; JEFFAMINE D-230, 22.86 
parts; and TiPure R-900, 6.16 parts. These components were mixed at a 
volume ratio of 1.00 (1.00 weight ratio) using the same spray equipment in 
Examples I and II. The resulting aliphatic polyurea elastomer had an 
effective gel time of 1.5 seconds with a tack free time of less than 5 
seconds. Formulation and elastomer physical properties are described in 
Table I. The minimum uniform film thickness obtainable was 25 mils (0.025 
inches). 
COMATIVE EXAMPLE IV 
Again, for comparison, this Example used a system with the same A-Component 
(isocyanate quasi-prepolymer component) as described in Example III. The 
B-component used was a blend of JEFFAMINE T-5000, 27.0 parts; JEFFAMINE 
D-2000, 27.0 parts; JEFFAMINE T-403, 17.6 parts; and JEFFAMINE D-230, 28.4 
parts. These components were mixed at a volume ratio of 1.00 (1.00 weight 
ratio) using the same spray equipment in Examples I, II, and III. 
Reactivity of this system was similar to that of Example III. Formulation 
and elastomer physical properties are mentioned in Table I. The minimum 
uniform film thickness obtainable was 25 mils (0.025 inches). 
TABLE I 
______________________________________ 
Elastomer Physical Properties for Examples I-IV 
Example 
I II III IV 
______________________________________ 
Isocyanate quasi- 
prepolymer 
m-TMXDI 54.5 54.5 55.0 55.0 
JEFFAMINE D-2000 
36.4 36.4 45 45 
TEXACAR PC 9.1 9.1 -- -- 
NCO, % 16.8 16.8 16.6 16.6 
Resin blends 
JEFFAMINE T-5000 
24.9 22.8 19.25 27.0 
JEFFAMINE D-2000 
24.9 22.8 28.87 27.0 
JEFFAMINE T-403 
18.7 17.1 22.86 17.6 
JEFFAMINE D-230 
27.4 27.4 22.86 28.4 
TiPure R-900 4.1 9.9 6.16 -- 
Processing 
INDEX 1.05 1.05 1.05 1.05 
Iso/Resin vol. ratio 
1.00 1.00 1.00 1.00 
Effective gel time, 
2.0 2.0 1.5 1.5 
sec. 
Tack free, sec. 
10 10 &lt;5 &lt;5 
Physical Properties 
Tensile strength, psi 
1200 2035 1415 1250 
Elongation, % 
475 535 400 395 
Tear strength, pli 
205 335 260 285 
Shore D Hardness 
35 45 40 42 
100% Modulus, psi 
525 835 665 635 
300% Modulus, psi 
775 1225 1110 945 
______________________________________ 
It may be seen that the physical properties of the elastomers of Examples I 
and II are the about the same as or improved over the elastomers 
Comparative Examples III and IV. The elastomers containing propylene 
carbonate also had improved processing characteristics, as noted. 
EXAMPLES V, VI & VII 
For additional illustration, three systems were prepared utilizing 
cycloaliphatic diamine chain extenders as well as the low molecular weight 
polyetheramines. These Examples used the same isocyanate component given 
in Examples I and II, above. Formulation and elastomer physical property 
information is shown in Table II. 
TABLE II 
______________________________________ 
Elastomer Physical Properties for Examples V-VII 
Example 
V VI VII 
______________________________________ 
Isocyanate quasi-prepolymer 
m-TMXDI 54.5 54.5 54.5 
JEFFAMINE D-2000 
36.4 36.4 36.4 
TEXACAR PC 9.1 9.1 9.1 
NCO, % 16.8 16.8 16.8 
Resin blends 
JEFFAMINE T-5000 
24.0 32.8 25.1 
JEFFAMINE D-2000 
24.0 32.8 -- 
JEFFAMINE T-403 -- -- 37.6 
JEFFAMINE D-230 19.2 -- -- 
VESTAMIN .RTM. IPD 
-- 30.3 5.0 
XTA-110 -- -- 28.2 
TiPure R-900 4.0 4.1 4.1 
Processing 
INDEX 1.05 1.05 1.05 
Iso/Resin vol. ratio 
1.00 1.00 1.00 
Effective gel time, sec. 
2.0 2.0 3.0 
Tack free, sec. 10 10 10 
Physical Properties 
Tensile strength, psi 
895 1545 1400 
Elongation, % 395 330 170 
Tear strength, pli 
230 345 210 
Shore D Hardness 
34 41 41 
100% Modulus, psi 
690 1255 1035 
300% Modulus, psi 
815 1415 -- 
______________________________________ 
EXAMPLE VIII 
This Example used an isocyanate component, (A) component, of a blend of 
AIRTHANE.RTM. XACP-722, 45.45 parts; AIRTHANE XACP-504, 45.45 parts; and 
TEXACAR PC, 9.1 parts. This resulting isocyanate component had a viscosity 
of 1000 to 1300 cps, as compared to well over 20,000 cps without the 
TEXACAR PC, making it processable. The (B) component used was a blend of 
JEFFAMINE T-5000, 35.1 parts; JEFFAMINE D-2000, 52.6 parts, VESTAMIN IPD, 
7.2 parts; and TiPure R-900, 5.1 parts. These components were mixed at a 
volume ratio of 1.00 (1.00 weight ratio) using the same spray equipment 
mentioned in previous Examples. Formulation and elastomer physical 
property information are seen in Table III. 
TABLE III 
______________________________________ 
Elastomer Physical Properties for Example VIII 
Example VIII 
______________________________________ 
Isocyanate quasi-prepolymer 
AIRTHANE XACP-722 45.45 
AIRTHANE XACP-504 45.45 
TEXACAR PC 9.1 
NCO, % 6.4 
Resin blends 
JEFFAMINE T-5000 35.1 
JEFFAMINE D-2000 52.6 
VESTAMIN IPD 7.2 
TiPure R-900 5.1 
Processing 
INDEX 1.05 
Iso/Resin vol. ratio 
1.00 
Effective gel time, sec. 
3.0 
Tack free, sec. &gt;1 hr. 
Physical Properties 
Tensile strength, psi 
690 
Elongation, % 300 
Tear strength, pli 90 
Shore D Hardness 39 
100% Modulus, psi 375 
300% Modulus, psi 46 
______________________________________ 
EXAMPLES IX, X, XI, XII & XIII 
These Examples illustrate the use of TEXACAR EC-50 in the isocyanate 
component. The elastomers will be processed as Examples I, II, V, VI and 
VII. Based on previous experiences, these Examples should exhibit the same 
characteristics as before. Formulation information is presented in Table 
IV. 
TABLE IV 
______________________________________ 
Elastomer Physical Properties for Examples IX-XIII 
Examples 
IX X XI XII XIII 
______________________________________ 
Isocyanate quasi- 
prepolymer 
m-TMXDI 54.5 54.5 54.5 54.5 54.5 
JEFFAMINE D-2000 
36.4 36.4 36.4 36.4 36.4 
TEXACAR EC-50 
9.1 9.1 9.1 9.1 9.1 
NCO, % 16.8 16.8 16.8 16.8 16.8 
Resin blends 
JEFFAMINE T-5000 
24.9 24.9 22.8 5.1 5.0 
JEFFAMINE D-2000 
24.9 -- 22.8 58.1 53.6 
JEFFAMINE D-4000 
-- 24.0 -- -- -- 
JEFFAMINE T-403 
18.7 19.2 17.1 -- -- 
JEFFAMINE D-230 
27.4 28.8 27.4 -- -- 
VESTAMIN IPD -- -- -- 26.9 -- 
XTA-100 -- -- -- -- 31.5 
TiPure R-900 4.1 4.0 9.9 9.9 9.9 
Processing 
INDEX 1.05 1.05 1.05 1.05 1.05 
Iso/Resin vol. ratio 
1.00 1.00 1.00 1.00 1.00 
______________________________________ 
EXAMPLES XIV-XIX 
These Examples will illustrate the application of the method of this 
invention to formulations where the isocyanate used in the 
quasi-prepolymer is an aromatic isocyanate. The results are reported in 
Table V. 
TABLE V 
__________________________________________________________________________ 
Elastomer Physical Properties for Examples XIV-XIX 
Example 
XIV XV XVI XVII XVIII 
XIX 
__________________________________________________________________________ 
Isocyanate-quasi-prepolymer 
RUBINATE .RTM. X 9015 
100 90 -- -- -- -- 
RUBINATE .RTM. X 9009 
-- -- 100 90 -- -- 
MONDUR .RTM. ML 
-- -- -- -- 55 49.5 
TEXOX .RTM. PPG-2000 
-- -- -- -- 45 40.5 
TEXACAR PC -- 10 -- 10 -- 10 
NCO, % 15.5 14.0 15.5 14.0 16.5 14.8 
Resin blends 
JEFFAMINE D-2000 
70.0 70.0 70.0 70.0 70.0 70.0 
ETHACURE .RTM. 100 
30.0 30.0 30.0 30.0 30.0 30.0 
Processing 
INDEX 1.05 0.95 1.05 0.95 1.07 0.98 
Iso/Resin vol. ratio 
1.00 1.00 1.00 1.00 1.00 1.00 
Effective gel time, sec. 
2.6 2.9 2.6 3.4 4.4 5.5 
Physical Properties 
Tensile strength, psi 
2515 2325 2730 2215 2830 2230 
Elongation, % 240 250 220 230 360 405 
Tear strength, pli 
435 390 485 395 500 465 
Shore D Hardness 
49 52 49 42 48 51 
100% Modulus, psi 
1665 1540 1845 1530 1475 1275 
300% Modulus, psi 
-- -- -- -- 2385 1865 
__________________________________________________________________________ 
From reviewing Table V, it may be seen that the addition of propylene 
carbonate to systems of Examples XV, XVII and XIX using aromatic 
polyisocyanates also lengthens the gel time of the system as compared with 
the elastomers of Examples XIV, XVI and XVIII. The physical properties of 
the elastomers using propylene carbonate are about the same as those 
without. 
Many modifications may be made in the process of this invention without 
departing from the spirit and scope thereof which are defined only in the 
appended claims. For example, one skilled in the art may discover that 
particular combinations of components with the alkylene carbonates or 
proportions therewith may give polyurea elastomers with advantageous 
properties. 
GLOSSARY 
AIRTHANE.RTM. XAPC-504 Isocyanate prepolymer of isophorone diisocyanate and 
a PTMEG polyol, with an equivalent weight of 504 and a functionality of 
2.6, viscosity &gt;40,000 cps. A product of Air Products. 
AIRTHANE.RTM. XAPC-722 Isocyanate prepolymer of isophorone diisocyanate and 
a PTMEG polyol, with an equivalent weight of 722 and a functionality of 
2.0, viscosity &gt;10,000 cps. A product of Air Products. 
ETHACURE.RTM. 100 A diethyltoluenediamine product of Ethyl Corp. 
JEFFAMINE.RTM. D-230 An amine-terminated polyoxypropylene diol of 230 
molecular weight available from Huntsman Corporation, used as a chain 
extender. 
JEFFAMINE.RTM. D-2000 An amine-terminated polyoxypropylene diol of 2000 
molecular weight available from Huntsman Corporation. 
JEFFAMINE.RTM. D-4000 An amine-terminated polyoxypropylene diol of 4000 
molecular weight available from Huntsman Corporation. 
JEFFAMINE.RTM. T-403 An amine-terminated polyoxypropylene triol of 400 
molecular weight available from Huntsman Corporation. 
JEFFAMINE.RTM. T-5000 An amine-terminated polyoxypropylene triol of 5000 
molecular weight available from Huntsman Corporation. 
MONDUR.RTM. ML A liquid uretonimine-modified methylenediisocyanate product 
of Miles, Inc. 
m-TMXDI.RTM. m-Tetramethylxylene diisocyanate from Cytec Industries 
(American Cyanamid). 
RUBINATE.RTM. X 9009 An aromatic polyisocyanate quasi-prepolymer made by 
ICI Polyurethanes. 
RUBINATE.RTM. X 9015 An aromatic polyisocyanate quasi-prepolymer made by 
ICI Polyurethanes. 
TEXACAR.RTM. EC-50 A proprietary blend of ethylene and propylene carbonate 
from Huntsman Corporation. 
TEXACAR.RTM. PC Propylene carbonate from Huntsman Corporation. 
TEXOX.RTM. PPG-2000 A polypropylene glycol product having a molecular 
weight of 2000 of Huntsman Corporation. 
TiPure.RTM. R-900 Titanium dioxide available from E. I. du Pont de Nemours, 
Co. 
VESTAMIN.RTM. IPD Isophorone diamine from Huls America, used as a chain 
extender. 
XTA-110 Experimental cycloaliphatic diamine of 194 molecular weight from 
Huntsman Corporation, used as a chain extender.