Reactive glass component in rim

The invention is a reinforced reaction injection molded elastomer made by reacting in a closed mold amine terminated polyethers of greater than 1500 average molecular weight, having greater than 50% of their active hydrogens in the form of amine hydrogens, a chain extender, an aromatic polyisocyanate, a filler and an effective amount of a silane having the formula: EQU (R').sub.y --Si--(R).sub.x where x+y=4; R' is a hydrophobic moiety and R is an alkoxy group, preferably methoxy or ethoxy.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention concerns the field of reaction injection molded elastomers. 
Reaction injection molded elastomers make excellent molded parts useful, 
for example, in the automobile industry as exterior parts for vehicles. 
2. Description of Related Publications 
U.S. Pat. Nos. 4,396,729; 4,444,910 and 4,433,067 concern elastomers 
prepared using a high molecular 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. 
U.S. Pat. No. 4,585,850 concerns and claims a reaction injection molded 
elastomer made by reacting in a closed mold amine terminated polyethers 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 amino silane coupling agent, and an aromatic 
polyisocyanate. The '850 patent referred to above contains a discussion of 
other applications and patents in the field and is incorporated herein by 
reference. 
Included in the discussion in the '850 patent are U.S. Pat. Nos. 4,474,900, 
4,582,887 and Ser. No. 763,502 filed Aug. 8, 1985 which will issued as 
U.S. Pat. No. 4,607,090 on Aug. 19, 1986 relate to various types of glass 
fillers in RIM. The disclosures of these are also incorporated herein by 
reference. 
An article in Plastics Engineering (May 1978) by John Foley of Witco 
Chemical Corp. discusses the use of surfactants as internal mold release 
agents. 
Quillery's U.S. Pat. No. 3,523,918 describes the use of amine chain 
extenders for the preparation of integral skin foams. Also, Weber, et 
al's. U.S. Pat. No. 4,218,543 describes the use of high molecular weight 
polyols, certain aromatic diamines and isocyanates for the production of 
RIM parts. This Bayer patent specifically claims as a chain extender 
1-methyl-3,5-diethyl-2,4-diaminobenzene (diethyltoluene diamine) and its 
isomer. 
Turner's U.S. Pat. No. 4,246,363 claims a RIM polyurethane composition 
derived from using at least three different polyols (including amine 
terminated polyethers) having specific relationships and reactivity and 
solubility parameters to one another. Also, Vanderhider's U.S. Pat. No. 
4,269,945 claims a process for preparing RIM polyurethanes wherein a 
relatively high molecular weight hydroxyl containing polyol, a chain 
extender and a polyisocyanate are used. The chain extender may be an 
aliphatic amine containing material having at least one primary amine 
group. 
The paper "Silane Effects and Machine Processing in Reinforced High Modulus 
RIM Urethane Composites," by E. G. Schwartz, et al., Journal of Elastomers 
and Plastics, volume 11 (October 1979), page 280, describes the use of 
silane treated milled glass fibers in reinforced RIM composites. 
The article "Surface Modification for RRIM Urethanes," by Ed Galli, 
Plastics Compounding, (January/February 1982) discloses silane treated 
glass fiber reinforcement of RRIM urethanes. The emphasis is on amino 
silanes. 
The publication "Silane Coupling Agents," by Dow-Corning Corporation 
discusses various silane coupling agents and their applications. 
U.S. Pat. No. 4,474,900 discloses and claims the use of epoxy modified 
filler material in RIM elastomers made from high molecular weight amine 
terminated polyethers and/or polyols. 
An advertisement and specification sheet for the product GLASSCLAD.RTM. 18 
(described as a monomeric octadecylsilane derivative in a solution of 
t-butanol and diacetone alcohol) discloses its use as surface treatment 
for glass. GLASSCLAD 18 is available from Petrarch Systems of Levittown, 
PA. 
We have found that the impact properties of reinforced reaction injection 
molded elastomers (RRIM) are improved by the use of 
octadecyltriethoxysilane believed to be the monomeric octadecylsilane 
derivative in GLASSCLAD 18 discussed above. 
SUMMARY OF THE INVENTION 
The invention is a reinforced reaction injection molded elastomer made in a 
closed mold ingredients comprising polyols of greater than about 500 
equivalent weight and/or amine terminated polyethers of greater than 1500 
average molecular weight, having greater than 50% of their active 
hydrogens in the form of amine hydrogens, a chain extender and an aromatic 
polyisocyanate, having also present additives comprising a filler and an 
effective amount of of a silane having the formula: 
EQU (R').sub.y --Si--(R).sub.x 
where x+y=4; R' is a hydrophobic moiety and R is an alkoxy group, 
preferably methoxy or ethoxy. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The polyols useful in the process of this invention include polyether 
polyols, polyester diols, triols, tetrols, etc., having an equivalent 
weight of at least 500, and preferably at least 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. In order to 
achieve the rapid reaction rates which are normally required for molding 
RIM polyurethane elastomers, it is preferable that the polyol be capped 
with enough ethylene oxide to increase the reaction rate of the 
polyurethane mixture. Normally at least 50% primary hydroxyl is preferred, 
although amounts of primary hydroxyl less than this are acceptable if the 
reaction rate is rapid enough to be useful in industrial application. 
Other high molecular weight polyols which may be useful in this invention 
are polyesters or hydroxyl terminated rubbers (such as hydroxyl terminated 
polybutadiene). Hydroxyl terminated quasi-prepolymers of polyols and 
isocyanates are also useful in this invention. 
Amine terminated polyethers including primary and secondary amine 
terminated polyether polyols of greater than 1500 average molecular weight 
from 2 to 6 functionality, preferably from 2 to 3, and an amine equivalent 
weight from about 750 to about 4000 are useful in this invention. Mixtures 
of amine terminated polyethers may be used. In a preferred embodiment the 
amine terminated polyethers have an average molecular weight of at least 
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, 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 prior art techniques, for example, as 
outlined in U.S. Pat. No. 3,654,370, incorporated herein by reference. 
In the practice of this invention, a single high molecular weight amine 
terminated polyether resin 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, mixtures of polyols and amine terminated polyethers are included 
within the scope of my invention. 
The chain extenders useful in the process of this invention are preferably 
difunctional. Mixtures of difunctional and trifunctional chain extenders 
are also useful in this invention. Th chain extenders useful in this 
invention include diols, (ethylene glycol and 1,4-butane diol, for 
example) amino alcohols, diamines or mixtures thereof. 
The aromatic diamine 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

A), 1,3,5-triethyl-2,6 diaminobenzene, 
3,5,3',5'-tetraethyl-4,4" diaminodiphenylmethane and 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 diaminobenzene. It is within the scope of this 
invention to include some aliphatic chain extender materials as described 
in U.S. Pat. Nos. 4,246,363 and 4,269,945. 
Other chain extenders which find use in the method of this invention are 
low molecular weight polyoxyalkylene polyamines which contain terminal 
amine groups and are represented by the formula: 
##STR1## 
wherein x+y+z has a value of about 5.3. The average amine hydrogen 
equivalent weight is about 67 and the product is commercially available 
from Texaco Chemical Company as JEFFAMINE.RTM. T-403. Another related 
polyoxypropylene polyamine is represented by the formula 
##STR2## 
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 also 
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 be apparent to those skilled in the art and the 
above recitation is not intended to be a limitation on the invention 
claimed herein. 
A wide variety of aromatic polyisocyanates may be used here. Typical 
aromatic polyisocyanates include p-phenylene diisocyanate, polymethylene 
polyphenylisocyanate, 2,6-toluene diisocyanate, dianisidine diisocyanate, 
bitolylene diisocyanate, naphthalene-1,4-diisocyanate, 
bis(4-isocyanatophenyl)methane, bis(3-methyl-3-isocyantophenyl)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. Pat. Nos. 2,683,730; 
2,950,263; 3,012,008; 3,344,162 and 3,362,979. 
Usually methylene-bridged polyphenyl polyisocyanate mixtures contain about 
20 to about 100 weight percent methylene diphenyldiisocyanate isomers, 
with the remainder being polymethylene polyphenyl diisocyanates having 
higher functionalities and higher molecular weights. Typical of these are 
polyphenyl polyisocyanate mixtures containing about 20 to 100 weight 
percent methylene diphenyldiisocyanate isomers, of which 20 to about 95 
weight percent thereof is the 4,4'-isomer with the remainder being 
polymethylene polyphenyl polyisocyanates of higher molecular weight and 
functionality 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. Pat. No. 
3,362,979, issued Jan. 9, 1968 to Floyd E. Bentley. 
By far the most preferred aromatic polyisocyanate is methylene 
bis(4-phenylisocyanate) or MDI. Pure MDI, quasi-prepolymers of MDI, 
modified pure MDI, etc. Materials of this type may be used to prepare 
suitable RIM elastomers. Since pure MDI is a solid and, thus, often 
inconvenient to use, liquid products based on MDI are often used and are 
included in the scope of the terms MDI or methylene 
bis(4-phenylisocyanate) used herein. U.S. Pat. No. 3,394,164 is an example 
of a liquid MDI product. More generally uretonimine modified pure MDI is 
included also. This product is made by heating pure distilled MDI in the 
presence of a catalyst. The liquid product is a mixture of pure MDI and 
modified MDI: 
##STR3## 
Examples of commercial materials of this type are Upjohn's 
ISONATE.RTM.125M (pure MDI) and ISONATE 143L ("liquid" MDI). Preferably 
the amount of isocyanates used is the stoichiometric amount based on all 
the ingredients in the formulation or greater than the stoichiometric 
amount. 
Of course, the term polyisocyanate also includes quasi-prepolymers of 
polyisocyanates with active hydrogen containing materials. 
If needed, the following catalysts are useful. Catalysts such as tertiary 
amines or an organic tin compound or other polyurethane catalysts are 
used. The organic tin compound may suitably be a stannous or stannic 
compound such as a stannous salt of a carboxylic acid, a trialkyltin 
oxide, a dialkyltin 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, dibutyltin 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-alkylmorpholines (e.g., 
N-methylmorpholine, N-ethylmorpholine, dimethyldiaminodiethylether, etc.), 
1,4-dimethylpiperazine, triethylenediamine, etc., and aliphatic polyamines 
such as N,N,N'N'-tetramethyl-1,3-butanediamine. 
Other conventional formulation ingredients may be employed 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. 
The filler materials useful in this invention are those known to be useful 
in RRIM elastomers. For example, flaked glass, process mineral fiber, 
milled glass, mica, fiberglass and Wallastonite. 
The impact properties of these RRIM elastomers having incorporated therein 
filler materials such as those discussed above are improved by the 
addition to the formulation for making the RRIM product certain silane 
materials represented by the general structure: 
EQU (R').sub.y --Si--(R).sub.x 
where x+y=4; R' is a hydrophobic moiety and R is an alkoxy group, 
preferably methoxy or ethoxy. 
For example, R' may be an alkyl group, an aryl or an alkyl aryl group of 
hydrophobic nature. For example, the monomeric octadecyltriethoxy silane 
was used in the examples which follow. Other R' groups which would be 
hydrophobic would be apparent to those skilled in the art. One such 
compound would define R' as 
##STR4## 
As noted above, the invention may be practiced by adding directly to the 
formulation for making the RIM product the silane materials just 
described. Alternatively, the filler used in the RRIM elastomer can be 
pretreated with neat silane materials noted above, or solutions of the 
silane materials noted above, as well as mixtures of the same. The 
pretreated filler can then be used in the RRIM formulation without having 
to add the silane material to the formulation as described previously. 
The pretreated filler material can also be used in other areas such as 
injection molding of glass filled nylons and similar materials.