FIELD OF THE INVENTION The invention relates to new and improved aromatic diol compounds and methods for making and using the same. The present compounds are useful as chain extenders and plasticizers for thermoset and thermoplastic urethanes, and are particularly suited for use in preparing cast polyurethanes.

BACKGROUND OF THE INVENTION Cast polyurethanes have a wide range of applications due to their unique combination of valuable physical and mechanical properties. In general, these elastomers can be prepared by the extension reaction of either polyether or polyester based isocyanate prepolymers with diol or diamine type chain extenders.

Both polyether and polyester based elastomers have excellent tensile strength, abrasion resistance, and load bearing characteristics far superior to other elastomeric materials. To achieve an optimum performance for a particular application, various chain extenders are being used with toluene diisocyanate ("TDI") and 4,4'- diphenylmethane diisocyanate ("MDI") terminated prepolymers based on polyether or polyester polyols. In the case of MDI-terminated prepolymers, 1,4-butanediol ("BD") is the most commonly used chain extender. Though the physical and

mechanical properties of elastomers based on BD chain extenders are excellent, these elastomers have limited thermal stability.

Methylene-bis-ortho-chloroaniline or"MOCA"is a commonly used curing agent for TDI prepolymers, but concerns regarding its hazardous nature continue to be an issue in various industries. Other diols, such as solid resorcinol bis-(ß-hydroxyethyl)(ß-hydroxyethyl) ether, melting point = 89°C, and solid hydroquinone bis- (j3- hydroxyethyl) ether, melting point = 102°C, have been tested for various applications, as reported in Plastics Technology,"For Non-MOCA Urethanes- Solve MDI Prepolymer Processing Problems", Hagen, September 1978, and RPN Technical Notebook, Fujiwara,"New Polyester-Polyether Coprepolymers", April 28,1980. A Koppers Company Data Sheet"HER", January 15,1978, described resorcinol bis- (ß-hydroxyethyl) ether as being useful as a chain extender which, when used in the formulation of urethane elastomers, provided improved hardness, tensile strength and elongation properties. Resorcinol bis-(ß-hydroxyethyl) ether was also characterized as having a low melting point 89°C (102°F) and good solubility in organic solvents.

Addition of both aromatic diols such as bis- (ß-hydroxyethyl) ethers of resorcinol and hydroquinone to polyurethanes helps to maintain mechanical properties of the polyurethanes at elevated temperatures. Although these ethers possess similar molecular structures, they have different processing characteristics in the cured elastomers. For example, hydroquinone bis- (fl-hydroxyethyl) ether has a substantially higher melting point than resorcinol bis- (ß-hydroxyethyl) ether, about 102°C versus about 89°C. In order to use hydroquinone bis-(ß-hydroxyethyl) ether in cast urethane applications, the mixture must be processed at temperatures higher than 100°C and possibly as high as 120°-130°C. If lower temperatures are used, then"starring"occurs due to the localized concentration of hydroquinone bis- (O- hydroxyethyl) ether in the elastomer system. To overcome the processing problems associated with hydroquinone bis- (ß-hydroxyethyl) ether, resorcinol bis- (O- hydroxyethyl) ether is used, as its lower melting point allows for a more forgiving chemistry and greater processing ease.

European Patent No. 0 525 038 B1 (Summer et al.) discloses high yield, high purity resorcinol bis- (ß-hydroxyethyl) crystals made by a three step process. This process involves: contacting resorcinol with ethylene carbonate in

the presence of water and an alkali metal carbonate, at about 130°C-150°C for about 1 hr.-10 hrs.; adding a solution of water and sodium hydroxide to the cooled reaction product, at 90°C; and allowing the mixture to cool to 20°C to precipitate solid resorcinol bis- (O-hydroxyethyl) crystals which are then collected by filtration.

U. S. Patent No. 5,059,723 (Dressler) discloses using a triorganophosphine as a catalyst during reaction of phenolic or thiophenolic compounds and a cyclic organic carbonate; when resorcinol and ethylene carbonate are used, ultra pure, solid crystals of resorcinol bis- (fl-hydroxyethyl) ether are produced.

Other discussion of common chain extenders are found, for example, in Mendelsohn et al., Rubber Chemistry And Technology,"Characteristics Of A Series Of Energy Absorbing Polyurethane Elastomers"Vol. 58, pp. 997-1013, April 1985; that article discusses the need for polyurethanes having specialized "soft-hard"engineering applications, such as damping vibration, mitigating shock, and also providing rigid structured members with"soft-hard"characteristics.

Extenders, such as 2-ethyl-1,3-hexanediol ("EHD"), BD, dipropylene glycol ("DPG"), resorcinol bis- (ß-hydroxyethyl) ether and hydroquinone bis- (, 8- hydroxyethyl) ether, were reported as being used in polyurethanes. Mendelsohn et al., U. S. Patent Nos. 4,485,719 and 4,604,940, further disclose elastomeric materials requiring specialized properties of both strength and rigidity for aerospace missile launch pads and flexible missile shock isolator pads. These materials used hydroquinone bis- (ß-hydroxyethyl) ether as the sole chain extender for their polyurethane formulations.

Resorcinol derivatives have been used in a variety of applications including polymers, pharmaceuticals, agricultural chemicals, and the like. In the case of cast, thermoplastic and adhesive urethane applications, the industry is looking for aromatic diol extenders, preferably diols having liquid or very low melting characteristics, for improving the processing and enhancing the physical and mechanical properties of the cured thermoplastic and thermoset type urethane materials. In addition to the polyurethane industry, other industries are looking for improved aromatic diol molecules for a variety of applications. Thus, there remains a need for improved aromatic diols.

SUMMARY OF THE INVENTION The present invention has met the above need by providing aromatic diol compounds that can be used in numerous applications, including as a combination chain extender/plasticizer in thermoplastic and thermoset urethane formulations. The present compounds impart excellent thermal stability and physical and mechanical properties and good damping and flexibility properties to these polyurethanes. Novel methods for preparing the present compounds are the further subject of the present invention. As discussed below, fluid diol compounds can be prepared according to the present invention. The term"fluid"as used herein refers to both liquid and semi-liquid products;"semi-liquid products"have, for example, the pourability of a liquid but are still somewhat viscous. Low melting point solids are also within the scope of the term"fluid diols", such solids having melting points generally less than about 100°C. The liquid, semi-liquid, and low melting point solids of the present invention provide enhanced processability when used as chain extenders with polyurethanes, other resins or even rubber compositions. The present aromatic diol compounds can be generally described as the reaction product of a dihydric phenolic compound and one or more alkylene carbonate compounds. The result is an aromatic diol comprised of an aromatic ring or ring system to which is attached two substituents in place of the hydroxy groups of the starting dihydric phenol. The substituents can be the same or different based upon the alkylene carbonates used in the reaction.

The present compounds can also be used in a variety of applications including polymers, pharmaceuticals, agricultural chemicals and the like.

It is therefore an object of the present invention to provide novel aromatic diol compounds having broad application in numerous industries.

It is a further object of this invention to provide such compounds in fluid form.

Another object of this invention is to provide methods for preparing the present aromatic diol compounds.

Yet another object of this invention is to provide products having improved mechanical and physical properties through use of the present compounds.

These and other objects of the invention will be apparent to those skilled in the art based upon the following disclosure and appended claims.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 illustrates a reaction scheme according to the present methods wherein resorcinol is reacted with ethylene carbonate, according to the methods generally described in Example 1.

Figure 2 illustrates a reaction scheme according to the present methods wherein resorcinol is reacted with ethylene carbonate in two stages, according to the methods generally described in Example 4.

Figure 3 illustrates a reaction scheme according to the present methods wherein resorcinol is reacted first with ethylene carbonate and then with propylene carbonate, according to the methods generally described in Example 9.

Figure 4 illustrates a reaction scheme according to the present methods wherein resorcinol is reacted first with propylene carbonate and then with ethylene carbonate, according to the methods generally described in Example 6.

Figure 5 illustrates a reaction scheme according to the present methods wherein resorcinol is reacted with propylene carbonate, according to the methods generally described in Example 10.

Figure 6 illustrates a reaction scheme according to the present methods wherein resorcinol is reacted with a mixture of propylene carbonate and ethylene carbonate.

Figure 7 provides DSC analysis for elastomers prepared using the present compounds, according to the methods of Example 15.

Figure 8 provides pot-life determinations for elastomers prepared using the present compounds, according to the methods of Example 15.

Figure 9 provides pot-life determinations for elastomers prepared using the present compounds, according to the methods of Example 15.

DETAILED DESCRIPTION OF THE INVENTION The present invention is generally directed to high molecular weight aromatic diols and methods for making and using the same. More specifically, the present invention is directed to aromatic diol compounds having the general formula (1): R-Z-R, (1) wherein Z is an aromatic moiety;

wherein R is represented by the general formula (2): HO (X).-; (2) wherein R, is represented by the general formula (3): -(Y).OH;(3) wherein each X and Y is the same or different and is independently selected from the group consisting of substituted or unsubstituted alkoxy groups; and wherein n = 2 to 4 and m = 2 to 4. The alkoxy groups can be straight chain, branched chain or cyclic, and are derived from alkylene carbonates as discussed below. In a preferred embodiment, X and Y are straight or branched chain alkoxy groups having the general formula CJI2, O, wherein a is between 2 and 5.

The aromatic moieties identified as"Z"in Formula 1 are generally derived from aromatic compounds, more specifically dihydric phenols which have two OH groups. Thus, as used herein, the term"dihydric phenol"refers to aromatic compounds having at least one aromatic ring to which are attached two hydroxy groups; when two rings are present in the dihydric phenol, one OH group is typically attached to each ring. Examples of suitable dihydric phenols having only one aromatic ring include, for example, resorcinol, hydroquinone and catechol.

Examples of suitable dihydric phenols having 2 or more aromatic rings include members of the bisphenol family generally represented by the formula (4): wherein Q is a straight chain, branched chain, or cyclic aliphatic having from 1 to 6 carbon atoms and R2 and R3 are the same or different and can be H, alkyl or aralkyl groups having 1-10 carbon atoms. Examples include bisphenol A, bisphenol F and bisphenol Z. The preferred bisphenol is bisphenol A (BPA) in which Q is 2,2- propylidene and the two OH groups are in the para position relative to the attachment point of Q. Other bisphenols which can be used include, but are not limited to, 4,4'-thiodiphenol and 4,4'-sulfonyl diphenol. Bisphenols are widely commercially available.

Resorcinol is the preferred dihydric phenol, particularly for use in the thermoset/thermoplastic polyurethane applications. Use of resorcinol to derive the aromatic moiety in the present compounds provides low viscosity diols in the range of 20 to 400 poise at 25°C, low to medium-high molecular weight, and imparts superior flexibility and low damping characteristics when used in the thermoplastic/thermoset polyurethane application. Resorcinol derived diols also impart outstanding strength characteristics to these resins, virtually eliminating the need for plasticizers.

"R"is generally represented by formula (2).

HO (X) (2) Similarly,"Rl"is generally represented by formula (3).

- (Y). OH(3) Each X and Y can be the same or different and is independently selected from the group consisting of straight, branched or cyclic alkoxy or aralkoxy groups. In preferred compounds X and Y have the formula CaH2aO, wherein a is between 2 and 5. Both"m"and"n"are also independently selected and can range between about 2 and 4. Thus, for each"R"or"R,"group there will be at least 2 but as many as 4"X"or"Y"groups, respectively. Each of the X groups can be the same or different; likewise each of the Y groups can be the same or different. That is, if n is 2, there will be 2"X"groups in the"R"substituent. One of these"X"groups may be, for example, CaH2aO wherein a is 2 and the chain is straight, while the other"X"group may be, for example, CaH2aO wherein a is 3 and the chain is branched. The formulas used herein are therefore intended to illustrate that each "diol"portion of the present aromatic diols can have mixed ether linkages.

As is discussed further below, the composition of each of the X and Y groups, and thus the R and R, groups, will vary depending on the materials utilized to make the compound. A preferred embodiment is one in which X and Y are both CaH2aO, n and m are both equal to 2 and a is equal to 2. In another preferred embodiment, X and Y are both CaH2aO, n and m both equal 2, one X group and one Y group is a branched chained alkyl group wherein a equals 3 and one X group and one Y group is a straight chain alkyl group wherein a equals 2.

An additional preferred embodiment is one in which the X and Y groups are both Cash2, and are branched chain alkyl groups in which a equals 3.

The substituents generally represented by"R"and"R,"are derived from alkylene carbonate compounds, which are cyclic compounds having the general formula (5): wherein R4 is selected from the group consisting of H, alkyl groups of C,-C, g carbon atoms, and aryl groups. Alkylene carbonates wherein R4 is H or CH3 are preferred for use with the present invention, specifically ethylene carbonate, propylene carbonate and mixtures thereof. Other particularly suitable compounds include, for example, 1,2-butylene carbonate and phenylethylene carbonate.

The present invention is also directed to a method for synthesizing the present aromatic diol compounds comprising mixing a dihydric phenol with one or more alkylene carbonates in the presence of a triorganophosphine catalyst, heating the mixture, and cooling the mixture to less than 100°C. During the reaction between dihydric phenol and the alkylene carbonate or carbonates, CO2 will be given off. The temperature at which the reaction is performed should be sufficient to initiate and maintain the evolution of CO2. This is typically in the range of 150°- 225°C. The reaction will be run to completion when CO2 is no longer generated.

Thus, heating should be maintained for a length of time sufficient to achieve the desired reaction between the starting materials. Typically this will be the amount of time needed to complete the reaction, as evidenced by the CO2 no longer being evolved. This period of time will vary depending on the nature and volume of the starting ingredients.

The present methods should be performed in an inert environment, such as an inert atmosphere of either CO2 and/or N2, although other inert conditions are equally within the scope of the invention.

The present reaction is run using a stoichiometric excess of alkylene carbonate. The molar ratio of dihydric phenol to alkylene carbonate should therefore be 1: greater than 2, preferably about 1: 2.05, more preferably about 1: 4; ratios as high as 1: 8 or even higher are also within the scope of the present invention. Above about 1: 8 however, the compound, when used as a chain

extender, may cause too much of a plasticizer effect, degrading strength and toughness of the final plastic in certain applications.

A novel feature of the diols, and methods of making the same, of the present invention is that fluid diols can be prepared. Fluid diols can result from the use of various starting materials and/or various dihydric phenol: carbonate molar ratios. More specifically, when propylene carbonate, either alone or in combination with other carbonates, is reacted with dihydric phenol in a molar ratio of dihydric phenol to carbonate of about 1: 2.05 or greater, the resulting aromatic diol will be fluid. Use of any of the other carbonates taught herein in a molar ratio of dihydric phenol to carbonate of about 1: 4 or greater will similarly result in a fluid aromatic diol. The discovery of fluid aromatic diols and methods of making the same will be regarded as a significant advance in industries using aromatic diols, since the fluid diols can be processed at much lower temperatures than solid diols. The needs and desires of the user, along with the particular application, will determine the optimum ratio of dihydric phenol to alkylene compound; such determination is well within the skill of those practicing in the art.

The dihydric phenols described above are suitable for use in the present methods including, but not limited to, resorcinol, hydroquinone, catechol and bisphenols. Again, resorcinol is the preferred dihydric phenol. Similarly, one or more of the alkylene carbonates described above can be utilized here. Preferred are ethylene carbonate and/or propylene carbonate. If the carbonates are in solid form, they are preferably melted before being combined with the dihydric phenol and catalyst. In addition, in some instances ethylene oxide and/or propylene oxide can be employed in place of or in addition to the cyclic organic carbonates described.

Triorganophosphine compounds useful as the catalyst in the present reactions are represented by formula (6): wherein R5, R6 and R7 are independently selected from alkyl groups, aryl groups, alkylaryl groups or mixtures thereof. The triorganophosphine compound may be triaryl, trialkyl, trialkylaryl, or mixed aryl/alkyl. Examples of such catalysts include triphenylphosphine, tributylphosphine, diphenylbutylphosphine and

dibutylphenylphosphine. The preferred catalysts are triarylphosphines, particularly triphenylphosphine. Triorganophosphine compounds are widely commercially available, or can be made using the Grignard reaction, which will be known to those skilled in the art.

The amount of triorganophosphine compound necessary to effectively catalyze the present reaction will vary depending on the particular dihydric phenol, the particular cyclic organic carbonate or carbonates and the particular triorganophosphine compound. The amount of catalyst is also dependent on desired reaction time, temperature and pressure. In general, the amount of catalyst will be between 0.0005 wt% to 5 wt% based on the weight of the dihydric phenol.

Preferably, the catalyst will be between 0.003 and 2 percent by weight based on the weight of the phenolic compound.

The triorganophosphine catalyst may be used alone or in combination with other known hydroxyalkylation catalysts, such as alkali and alkali earth metal salts, hydroxides, carbonates, etc. Similarly, the alkali/alkali earth metal catalysts can be used alone : The catalyst may be utilized in an unsupported state or in an supported state. Suitable supports include alumina, silica gel, diatomaceous earths, porous gas, zeolites, clays, and activated carbons. The methods of supporting the catalyst or the substrates are well known in the catalysis art. It is preferred that the triorganophosphine catalyst be used as the only catalyst and be used in the unsupported state.

The reaction of the phenolic compound with the cyclic organic carbonate in the presence of the triorganophosphine catalyst may take place in the presence or absence of appropriate solvents. The use of a solvent will be dependent on the particular phenolic compound, cyclic organic carbonate and catalyst being used. In the preferred embodiment solvents are not necessary.

As noted above, the process of the present invention may be run at any temperature and for any length of time suitable to drive off all or nearly all of the CO2. Monitoring the CO2 generation is therefore one means by which to determine when the reaction is complete. Because the most complete reaction of dihydric phenol and alkylene carbonate possible would be desired to optimize utilization of starting materials and give a pure product, it is therefore desired to drive off as much CO2 as possible. Generally, a suitable temperature will be

between 150°C and 225°C. The total reaction time will generally not be less than about 2 hours and can be as long as about 20 hours, or longer, depending on batch size.

It will be understood that the alkylene carbonate or carbonates can be reacted with the dihydric phenol in more than one stage. For example, a first carbonate compound can be reacted with the dihydric phenol in the presence of a triorganophosphine catalyst for a given amount of time. In a second stage, a second carbonate, which can be the same or different from the first carbonate, can be further reacted with the mixture. As many stages as desired can be employed, as long as the final desired ratio of 1: greater than 2 is achieved.

Various preferred embodiments of the present invention are illustrated in Figures 1-6. These figures generally represent preferred embodiments wherein resorcinol is the dihydric phenol, ethylene and/or propylene carbonate is the alkylene carbonate compound, and triphenylphosphine is the catalyst. It will be appreciated by those skilled in the art, however, that these reaction schemes are representative of any of the dihydric phenols, alkylene carbonates or catalysts within the scope of the present invention. It will be further appreciated that the products depicted in the Figures represent what is believed to be the predominant isomer formed during the reaction, but that a distribution of isomers would actually be formed; the present invention encompasses all such isomers. In addition, non- symmetrical distribution of the alkoxy groups does occur and higher or lower molecular weight species can be formed in addition to those shown in the Figures.

Finally, while certain primary and secondary hydroxyl substituents are shown, other variations are possible in both the intermediate products and final products.

Figure 1 depicts the reaction of one mole of resorcinol with four moles of ethylene carbonate, at a temperature of between 160°C and 165°C for approximately three to four hours. In the resulting product, a equals 2 for both the X and Y groups and n and m both equal 2.

In Figure 2, one mole of resorcinol is reacted with two moles of ethylene carbonate at a temperature of between about 160°C to 165°C for approximately three to four hours to form the intermediate product, resorcinol bis- (ß-hydroxyethyl) ether. The intermediate is then further reacted with two additional moles of ethylene carbonate under the same temperature and time parameters as the

first stage. In the resulting product, both X and Y equal 2 and m and n equal 2.

This product, which is the same as that shown in Figure 1, is achieved in two stages rather than one.

Figure 3 depicts the same first stage as that described for Figure 2.

The intermediate product, however, is then further reacted with two moles of propylene carbonate at a temperature of between about 180°C to 210eC for approximately three to four hours. In the resulting product, R and Rl are different in that R is a secondary hydroxyl whereas R, is a primary hydroxyl.

Figure 4 depicts the reaction of one mole of resorcinol with two moles of propylene carbonate at a temperature of between about 180°C to 210°C for three to four hours. The resulting intermediate is then further reacted with two moles of ethylene carbonate at a temperature of between about 160°C to 200°C for a time of three to four hours. In the resulting product, R and R, are isomeric equivalents with m and n both equal to 2. The X and Y groups closest to the aromatic ring are branched groups wherein a equals 3; the other X and Y groups are straight chains wherein a equals 2.

In Figure 5, one mole of resorcinol is reacted with four moles of propylene carbonate at a temperature of between about 180°C to 210°C for a time of approximately three to ten hours. In the resulting product, R and R, differ in that the final linkage of one is a secondary hydroxyl and the final linkage of the other is a primary hydroxyl.

Figure 6 depicts the reaction of one mole of resorcinol with a mixture of both ethylene carbonate and propylene carbonate. The two carbonates can be present in any amount between 0.5 and 2.0 moles, so long as the total moles of carbonate is greater than 2. The reaction is run at a temperature of between about 160°C and 210°C for approximately three to ten hours. Various products which can result from using the mixture of the carbonates at the same time are depicted in the figure. It will be understood that other structures are also possible when running this scheme.

The product resulting from the present methods can be used as is, or it may be further purified to remove any small amount of reaction product impurities, using common purification technique.

The high molecular weight aromatic diol compounds of the present invention are useful in any application wherein aromatic diols are needed or desired.

The compounds, however, find particular application in the thermoset/thermoplastic polyurethane applications, particularly in the preparation of cast polyurethanes. As discussed in the examples below, two new fluid aromatic diols are particularly useful in this application. The first of these products is the reaction product of resorcinol and ethylene carbonate with the hydroxyl number of 375-385 and room temperature viscosity of about 20 poise. The second diol product prepared according to the present invention is the result of the reaction of resorcinol, ethylene carbonate and propylene carbonate with a hydroxyl number of 345-355 and a viscosity of about 39 poise; this material contains about 50% primary hydroxyl groups per molecule. These unique products were generated by controlling reaction conditions and co-reactants, namely the different carbonates, to arrive at these superior products. Elastomers made from these products are softer than elastomers made with compounds known in the art; the elastomers made using the compounds of the present invention also appeared clearer and more transparent than elastomers made with art-known compounds.

For example, the elastomers made using the present compounds exhibited very low rebound values. It has been reported that soft polyurethanes with a low Bashore rebound (less than 20) are considered good energy absorbing materials for various applications. Typically, in order to achieve such energy absorbing soft polyurethane materials, use of plasticizers and/or trifunctional monomers are employed. Use of the compounds of the present invention in these applications eliminates the need to use plasticizers and triol curatives, which are know to affect the physical and mechanical properties of the resins to which they are added. In addition, elastomers prepared using the present aromatic diol compounds showed good overall physical and mechanical properties in addition to very low rebound values.

Thus, the present invention is also directed to a polyurethane composition and methods for making the same in which the present aromatic diol compounds have been used as a chain extender and/or plasticizer. These polyurethanes include thermoset and thermoplastic urethanes, preferably cast polyurethanes. These polyurethanes can be made by any means standardly reported

in the art, with the addition of the present aromatic diol compounds in place of the chain extenders and/or plasticizers reported as being used in those methods.

EXAMPLES The following examples are intended to illustrate the invention, and should not be construed as limiting the invention in any way. All of the synthesis examples were carried out under inert conditions of either N2 or CO2. When the reaction evolved CO2, the N2 could be minimized or eliminated; as CO2 evolution slowed or stopped, an N2 sparge was reintroduced.

EXAMPLE 1 88.1 g (1.0 mole) of solid ethylene carbonate was added to a 200 ml 3-necked flask equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflux condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes and heat was then applied to melt the ethylene carbonate. As the ethylene carbonate began to melt (35°C to 40°C), the stirrer was turned on and the stirring speed gradually increased until the molten ethylene carbonate was at a temperature of about 75°C to 80°C. At this point, the controller set point was adjusted to 110°C and 27.5 g (0.25 mole) of resorcinol and 0.38 g (0.00145 mole) of triphenylphosphine were added to the reaction flask as solid materials. The total molar ratio of phenolic compound to carbonate was 1 to 4. After the temperature stabilized at 110°C, the temperature was gradually raised to 165°C. At around 150°C to 155°C, the mixture began to evolve CO2. The pot temperature equilibrated at 160°C to 165°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 5.5 hours. The temperature was then gradually raised to 170°C for an additional reaction time of 1 hour. The reaction mass was then cooled to less than 100°C giving a clear light-yellow liquid. The yield was 71.6 g (99%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 376 (mg KOH/g sample).

The viscosity was approximately 20 poise at room temperature (about 25°C) and it remained liquid at room temperature upon storage.

EXAMPLE 2 The procedure of Example 1 was repeated using a 2-liter resin kettle instead of a 3-necked flask, 704.8 g (8.0 mole) of solid ethylene carbonate, 220.2 g (2.0 moles) of resorcinol and 3.0 g (0.00114 mole) of triphenylphosphine.

Additionally, the mixture was heated for a period of 4.5 hours, instead of 5.5 as in Example 1, after which time the temperature was raised to 175°C for an additional reaction time of 1 hour. The reaction mass was then cooled to less than 100°C giving a clear-yellow liquid. The yield was about 581.6 g (100%) which was confirmed by both compositional analysis by proton magnetic resonance techniques and hydroxyl number of 384 (mg KOH/g sample). The viscosity was approximately 20 poise at room temperature (about 25°) and it remained liquid at room temperature upon storage.

EXAMPLE 3 Example 2 was repeated using a 3-liter resin kettle, 1762 g (20.0 mole) of solid ethylene carbonate, 550.5 g (5.0 moles) of resorcinol and 1.5 g (0.0057 mole) of triphenylphosphine. Additionally, the mixture was heated for a period of 8.0 hours instead of 4.5 as in Example 2, after which time the temperature was raised to 185°C for an additional reaction time of 6 hours. The reaction mass was then cooled to less than 100°C giving a clear-yellow liquid. The longer reaction time in this example is due to the large batch size. The yield was 1446 g (100%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 379 (mg KOH/g sample).

The viscosity was approximately 20 poise at room temperature (about 25°) and it remained liquid at room temperature upon storage.

EXAMPLE 4 44.1 g (0.5 mole) of solid ethylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2) and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes and heat was then applied to melt the ethylene carbonate. As the ethylene carbonate began to melt (35°C to 40°C), the stirrer was turned on and the stirring speed gradually increased until the molten ethylene carbonate was at a temperature of 75°C to 80°C. At this point, the controller set point was adjusted to 110°C and 27.5 g (0.25 mole) of resorcinol and 0.38 g (0.00145 mole) of triphenylphosphine

were added to the reaction flask as solid materials. After the temperature stabilized at 110°C, the temperature was gradually raised to 165°C. At around 150°C to 155°C, the mixture began to evolve CO2. The pot temperature equilibrated at 165°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 1.5 hours. After an additional 15 minutes, the reaction mixture was cooled to 110°C and an additional charge of 44.0 g (0.5 mole) of solid ethylene carbonate was added to the clear yellow liquid in the flask. The total molar ratio of phenolic compound to ethylene carbonate was 1 to 4. The mixture was reheated to 165°C until a steady evolution of CO2 was again apparent. The temperature was then gradually raised to 185°C for an additional reaction time of about 2 hours and 30 minutes. The reaction mass was then cooled to less than 100°C giving a clear light-yellow liquid. The yield was 69.7 g (97%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 376 (Mg KOH/g sample). The viscosity was approximately 20 poise at room temperature (about 25 °C) and it remained liquid at room temperature upon storage.

EXAMPLE 5 44.1 g (0.5 mole) of solid ethylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflux condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes and heat was then applied to melt the ethylene carbonate. As the ethylene carbonate began to melt (35°C to 40°C), the stirrer was turned on and the stirring speed gradually increased until the molten ethylene carbonate was at a temperature of 75°C to 80°C. At this point, the controller set point was adjusted to 110°C and 27.5 g (0.25 mole) of resorcinol and 0.38 g (0.00145 mole) of triphenylphosphine were added to the reaction flask as solid materials. After the temperature stabilized at 110°, the temperature was gradually raised to 165°C. At around 150°C to 155°C, the mixture began to evolve CO2. The pot temperature equilibrated at 165°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 2 hours. After an additional 15 minutes, the reaction mixture was cooled to 110°C and an additional charge of 44.1 g (0.5 mole) of solid ethylene carbonate was added to the clear-yellow liquid. The mixture was the reheated to 165°C until

a steady evolution of CO2 was again apparent and held at this temperature for an additional reaction time of 4 hours and 15 minutes. The temperature was again dropped to 110°C and a final charge of 44.1 g (0.5 mole) of solid ethylene carbonate was added to the reaction mass. The total molar ratio of phenolic compound to the ethylene carbonate was 1 to 6. The temperature was raised to 165°C and a steady evolution of CO2 was again apparent. The temperature was gradually raised to 195°C for a final reaction period of 1 hour and 15 minutes. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid. The yield was about 96.8 g (100%) which was confirmed by both compositional analysis by proton magnetic resonance techniques and hydroxyl number of 281 (mg KOH/g sample). The viscosity was approximately 20 poise at room temperature (about 25°) and it remained liquid at room temperature upon storage.

EXAMPLE 6 51.0 g (0.5 mole) of liquid propylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes with stirring. At this point, the controller set point was adjusted to approximately 100°C and 27.7 g (0.25 mole) of resorcinol and 0.38 g (0.00145 mole) of triphenylphosphine were added to the reaction flask as solid materials. After the temperature stabilized 100°C, the temperature was gradually raised to 195°C. At around 190°C to 195°, the mixture began to evolve CO2. The pot temperature equilibrated at 195°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 3.5 hours. After an additional 15 minutes, the reaction mixture was cooled to 130°C and an additional charge of 44.2 g (0.5 mole) of solid ethylene carbonate and 0.2 g (0.00076 mole) of triphenylphosphine were added to the clear orange liquid for a two step process using two different carbonates. The total molar ratio of phenolic compound to carbonate was 1 to 4. The mixture was then reheated to 165°C until a steady evolution of CO2 was again apparent. The temperature was then gradually raised to 180°C for an additional reaction time of 4 hours and 15 minutes. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid. The yield was about 79.4 g (100%) which was conformed by both compositional analyses by proton magnetic resonance techniques

and hydroxyl number of 343 (mg KOH/g sample). The viscosity was approximately 38 poise to 40 poise at room temperature (about 25°C).

EXAMPLE 7 1021 g (10.0 mole) of liquid propylene carbonate were added to a 3- liter resin kettle, equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflux condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 60 minutes with stirring. At this point, the controller set point was adjusted to 150°C and 550.5 g (5.0 moles) of resorcinol and 1.5 g (0.0057 mole) of triphenylphosphine were added to the reaction flask as solid materials. After the temperature stabilized at 150°C, the temperature was gradually raised to 195°C. At around 190°C to 195°C, the mixture began to evolve CO2. The pot temperature equilibrated at 195°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 12 hours. After an additional 15 minutes, the reaction mixture was cooled to 100°C and an additional charge of 881 g (10.0 moles) of solid ethylene carbonate was added to the clear orange liquid for a two step process using two different carbonates. The total molar ratio of phenolic compound to carbonate was 1 to 4.

The mixture was then reheated to 195°C until a steady evolution of CO2 was again apparent. The temperature was then maintained for an additional reaction time of 5 hours for a total of about 17 hours. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid. The yield was 1552.6 g (99%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 355 (mg KOH/g sample). The viscosity was approximately 38 poise to 40 poise at room temperature (about 25°C) and it remained liquid at room temperature upon storage.

EXAMPLE 8 Example 4 was repeated, but rather than using a second charge of solid ethylene carbonate, a charge of 51.1 g (0.5 mole) of liquid propylene carbonate was added to the clear yellow liquid. The total molar ratio of phenolic compound to carbonate was still 1 to 4. The mixture was reheated to 165°C until a steady evolution of CO2 until a steady evolution of CO2 was again apparent. The temperature was then gradually raised to 185°C for an additional reaction time of 4 hours. The reaction mass was then cooled to less than 100°C giving a clear yellow

liquid. The yield was 76.9 g (97%) which was confirmed by both compositional analyses by proton magnetic resonance techniques a hydroxyl number of 367 (mg KOH/g sample).

EXAMPLE 9 44.2 g (0.5 mole) of solid ethylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2) and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes and heat was then applied to melt the ethylene carbonate. As the ethylene carbonate began to melt (35°C to 40°C), the stirrer was turned on and the stirring speed gradually increased until the molten ethylene carbonate was at a temperature of 55°C to 60°C. At this point, the controller set point was adjusted to 150°C, and 27.7 g (0.25 mole) of resorcinol and 0.38 g (0.00145 mole) of triphenylphosphine were added to the reaction flask as solid materials. After the temperature stabilized at 150°C, the temperature was gradually raised to 165°C. At around 150°C to 155°, the mixture began to evolve CO2. The pot temperature equilibrated at 165°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 3.0 hours. After an additional 15 minutes, an additional charge of 51.2 g (0.5 mole) of liquid propylene carbonate and an additional 0.38 g (0.00145 mole) of triphenylphosphine was added to the clear yellow liquid. The total molar ratio of phenolic compound to carbonate was 1 to 4. The mixture was then reheated to 165°C until a steady evolution of C02 was again apparent. The temperature was then gradually raised to 205°C for an additional reaction time of 5 hours. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid. The yield was 76.2 g (97%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 374 (mg KOH/g sample).

EXAMPLE 10 102.1 g (1.0 mole) of liquid propylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflux condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes with stirring. At this point, the controller set point was adjusted to 100°C and 27.6 g (0.25 mole) of resorcinol and 0.38 g (0.00145 mole) of triphenylphosphine were

added to the reaction flask as solid materials. The total molar ratio of phenolic compound to carbonate was 1 to 4. After the temperature stabilized at 100°C, the temperature was gradually raised to 195°C. At around 195°C, the mixture began to evolve CO2. The pot temperature equilibrated at 195°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 6.5 hours. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid. The yield was 71.4 g (83%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 393 (mg KOH/g sample).

The viscosity was about 200 poise (at room temperature (about 25°C).

EXAMPLE 11 88.1 g (1.0 mole) of solid ethylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflux condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes and heat was then applied to melt the ethylene carbonate. As the ethylene carbonate began to melt (35°C to 40°C), the stirrer was turned on and the stirring speed gradually increased until the molten ethylene carbonate was at a temperature of 75°C to 80°C. At this point, the controller set point was adjusted to 100°C and 57.1 g (0.25 mole) of recrystallized Bisphenol-A and 0.38 g (0.0045 mole) of triphenylphosphine were added to the reaction flask as solid materials. The total mole ratio of phenolic compound to carbonate was 1 to 4. After the temperature stabilized at 110°C, the temperature was gradually raised to 165°C. At around 150°C to 155°C, the mixture began to evolve CO2. The pot temperature equilibrated at 165°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 1.0 hour. The temperature was then gradually raised to 175°C for an additional reaction time of 2 hours and 15 minutes. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid. The yield was 101.2 g (100%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number of 261 (mg KOH/g sample).

EXAMPLE 12 88.1 g (1.0 mole) of solid ethylene carbonate were added to a 200 ml 3-necked flask, equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflux condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 30 minutes and heat was then applied to melt the ethylene carbonate. As the ethylene carbonate began to melt (35°C to 40°C), the stirrer was turned on and the stirring speed gradually increased until the molten ethylene carbonate was at a temperature of 75°C to 80°C. At this point, the controller set point was adjusted to 110°C and 27.3 g (0.25 mole) of hydroquinone and 0.38 g (0.00145 mole) of triphenylphosphine were added to the reaction flask as solid materials. The total molar ratio of phenolic compound to carbonate was 1 to 4. After the temperature stabilized at 110°C, the temperature was gradually raised to 165°C. At around 150°C to 155°C, the mixture began to evolve CO2. The pot temperature equilibrated at 165°C and a steady flow rate of CO2 evolved. The mixture was heated for a period of 6.0 hours. The reaction mass was then cooled to less than 100°C giving a clear light-yellow semi-liquid compound. The yield was 70.1 g (97%) which was confirmed by both compositional analyses by proton magnetic resonance techniques and hydroxyl number 366 (mg KOH/g sample).

EXAMPLE 13 210.4 g (2.06 moles) of liquid propylene carbonate were added to a 500-ml resin kettle, equipped with a stirrer, thermocouple well, nitrogen (N2) and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 60 minutes with stirring. At this point, the controller set point was adjusted to 100°C and 1101.1 g (1.0 mole) of resorcinol and 1.5 g (0.0057 mole) of triphenylphosphine were added to the reaction flask as sold materials. The total molar ratio of phenolic compound to carbonate was 1 to 2.06. After the temperature stabilized at 100°C, the temperature was gradually raised to 200°C. At around 180°C to 185°C, the mixture began to evolve CO2. The pot temperature equilibrated at 195°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 3.0 hours. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid with a green hue. The yield was 225.4 g (99%) which was confirmed by both compositional analysis by proton-magnetic resonance

techniques and hydroxyl number of 482 (mg KOH/g sample). The viscosity was about 200 poise at room temperature (about 25°C).

EXAMPLE 14 1472.8 g (14.4 moles) of liquid propylene carbonate were added to a 3-liter resin kettle, equipped with a stirrer, thermocouple well, nitrogen (N2) inlet, heating mantle and reflex condenser attached to a bubbler to monitor N2 and/or carbon dioxide (CO2) evolution rate. The vessel was purged with N2 for 60 minutes with stirring. At this point, the controller set point was-adjusted to 100°C and 770.7 g (7.0 moles) of resorcinol and 10.5 g (0.040 mole) of triphenylphosphine were added to the reaction flask as solid materials. The total mole ratio of phenolic compound to carbonate was 1 to 2.06. After the temperature stabilized at 110°C, the temperature was gradually raised to 190°C. At around 180°C to about 185°C, the mixture began to evolve CO2. The pot temperature equilibrated at 190°C, and a steady flow rate of CO2 evolved. The mixture was heated for a period of 4.0 hours. The reaction mass was then cooled to less than 100°C giving a clear yellow liquid with a green hue. The yield was 1596.7 g (100%) which was confirmed by both compositional analyses by proton-magnetic resonance techniques and hydroxyl number of 475 (mg KOH/g sample). The viscosity was about 200 poise at room temperature (about 25°C).

EXAMPLE 15 A liquid aromatic diol was prepared using resorcinol, Ph3P and ethylene carbonate, as generally taught in Examples 1-3; the product, referred to herein as"Diol A", had a viscosity of about 20 poise at 25°C and a hydroxyl number between 375 and 385. A second liquid aromatic diol was prepared using resorcinol, Ph3P and both propylene carbonate and ethylene carbonate as generally taught in Examples 6-7; the product, referred to herein as"Diol B", had a viscosity of about 39 poise at 25°C and a hydroxyl number between 340 and 355. To investigate the physical and mechanical properties of elastomers extended with Diol A and Diol B, cast polyurethanes were made using these compounds. Diols A and B were compared with cast polyurethanes made with resorcinol bis-(ß-hydroxyethyl) ether ("Diol C") and a product having a mixture of approximately 93% resorcinol bis-(ß-hydroxyethyl)(ß-hydroxyethyl) ether and 7% of the high molecular weight diol of the present invention, ("Diol D"). Diols C and D are commercially available from Indspec

Chemical Corporation as"HER'HP"and"HER'TG-210", respectively. The procedures for preparing and testing parameters of these polymers are detailed below.

ElastomerPreparation A known quantity of prepolymer, as identified in the Tables below, was weighed and placed in a glass vessel. The chain extender was weighed separately in another glass vessel to achieve an NCO/OH ratio of either 1.1/1 or 1.05/1 (% stoichiometry = 90 or 95, respectively). Both jars were placed in a vacuum oven at temperatures of between about 80°C and 110°C and held under vacuum until the bubbles disappeared, indicating that all the dissolved gases and any moisture, if present, had been removed. This process required about lmm Hg vacuum and 2.5 to 3.0 hours. After degassing, both the prepolymer and extender were thoroughly mixed for a period of one minute using a stirrer, avoiding bubbles.

The mix was then poured into a heated stainless steel plate mold treated with Teflon mold release agent. After pouring, the mold was placed in a programmable oven and cured for about 1 hour at 130° and 16 hours at 100°C. After this curing period, the samples were allowed to cool slowly to room temperature. The test specimens were cut from the cured sheet for tensile strength, tear strength and DMA analysis and then stored for at least 7 days at 22°C, 50% relative humidity conditions before testing. Compression set samples were prepared separately, following the degassing procedure similar to that for plate casting, and aged similarly before testing.

Test Methods The following test methods were used to determine the physical properties of the cast elastomers.

1. Tensile Strength, % elongation and modulus (ASTM D412).

2. Tear Strength, Die C (ASTM D 624).

3. Shore Hardness, Durometer A and D (ASTM D 2240).

4. Bashore Rebound (ASTM D 2632).

5. Compression Set % (ASTM D 395), Method B.

6. Dynamic Mechanical Analysis (DMA) was determined using a Rheometrics RMS-800 instrument at 1 Hz frequency with a heating rate of 2°C- 10°C/min.

7. DSC Analysis, DSC thermograms, of the cast elastomers were measured on a Perkin Elmer (DSC-7) at a heating rate of 10°C/minute under nitrogen atmosphere.

Results of the elastomer testing are presented in Tables 1 and 2 below.

In addition, pot life determinations of cast elastomers made with Diol D, as compared with a cast elastomer made with hydroquinone bis- (O-hydroxyethyl) ether (HQEE), were done using a Brookfield viscometer at controlled temperatures.

Results are presented in Figures 8 and 9. The cast elastomers were made as described above using either Baytec ME-050 or Baytec MS-242.

Table1 PREPOLYMER TYPE BAYTEC MS-242* CHAINEXTENDER Diol A Diol B Diol C Diol D PrepolymerTemperature, °C 80 80 110 85 Chain Extender Temperature, °C 80 80 110 85 Mix Ratio (Prepolymer/Chain Extender) 100/14.0 100/14.8 Stoichiometry, % Theory 90 90 90 90 Cure, HR/C 16/100 16/110 16/110 16/110 TENSILE PROPERTY 100% Modulus (PSI) 334 352 1798 1488 200% Modulus (PSI) 445 483 2436 2016 300% Modulus (PSI) 605 651 3071 2667 Tensile Strength (PSI) 2155 2050 4624 4959 l Elongation, % 473 466 645 622 Tear Strength, Die °C (Lb/in) 221 229 768 783 Compression Set, % 17.2 48 30.4 32.4 Bashore Rebound, % 3 3 NA 34 Hardness, Shore-A/D 69A 70A 45D 44D DYNAMIC MECHANICAL ANALYSIS Tan Delta at 10 HZ/23 °C (Frequency) 0.073 0.083 Tan Delta at 25° C (Temp. Sweep) 0.054 0.061 Tg (Tan Delta Peak) 9-24 Tg (G"Peak), °C-9.6-7.5-29. 4-30.1 THERMAL STABILITY (TEMP. MAX FOR CONSTANT G') Temperature, °C 150 150 150 150 G' (Dynes/cm2) x 108 0.25 0.25 1.48 1.47 * MDI-polyester prepolymer, 6.6% NCO, commercially available from Bayer Corporation Table 2 PREPOLYMERTYPE BAYTEC ME-050* CHAIN EXTENDER Diol A Diol B Diol C Diol D Prepolymer Temperature, °C 80 80 110 85 Chain Extender Temperature, °C 80 80 110 85 Mix Ratio (Prepolymer/Chain Extender) 100/17.9 100/18.4 100/12.5 100/12.1 Stoichiometry, % Theory 90 90 90 90 Cure, HR/C 16/100 16/110 16/110 16/110 TENSILEPROPERTY 100% Modulus (PSI) 429 325 1345 1182 200% Modulus (PSI) 603 403 1750 1612 300% Modulus (PSI) 1012 555 2214 2120 Tensile Strength (PSI) 1175 2011 3412 3780 Elongation, % 319 418 605 527 Tear Strength, Die °C (Lb/in) 201 180 626 558 Compression Set, % 25.8 27 14.6 17.6 Bashore Rebound, % 48 42 NA 63 Hardness, Shore-A/D 74A 67A 47D 43D DYNAMIC MECHANICAL ANALYSIS Tan Delta at 10 HZ/23 °C (Frequency) 0.086 0.052 0.038 0.034 Tan Delta at 25° C (Temp. Sweep) 0.05 0.03 0.032 0.024 Tg (Tan Delta Peak)-33.6-23.6-62.9-59.4 Tg (G"Peak), °C-61.3-45.4-70.4-68.8 THERMAL STABILITY (TEMP. MAX FOR CONSTANT G") Temperature, °C 150 150 160 155 G' (Dynes/cm2) x 108 1.55 1.42 * MDI-polyether prepolymer, 5.8% NCO, commercially available from Bayer Corporation

As can be seen from the above tables, the elastomers made from Diol A and Diol B had many properties desirable for resin applications. For example, these elastomers showed very low rebound properties and therefore would be good energy absorbing materials for various applications. The rebound properties are achieved without the need for plasticizers or trial curatives. Good overall physical and mechanical properties were also seen with these elastomers. The elastomers made from the present compounds also appeared clearer and more transparent.

Significantly, these properties were achieved by using a fluid chain extender, that provided for ease of handling and processability. The elastomer prepared with Diol D also had excellent properties, including high rebound, low tan delta, and low compression set values. Thus, even a small amount (i. e. 7%) of the present aromatic diol compounds yields enhanced results.

DSC curves were obtained during the first heating of the elastomers made with Diol A and Diol B liquid chain extenders. Results are shown in Figure 7. Diol A based elastomers showed very minor endothermic peaks around 213°C (MS-242) and 221°C (ME-050) and liquid Diol B did not show any transition behavior between room temperature and 200°C indicating the absence of any crystalline hard segments in this system. These results suggest that the hard segment formed between Diol A or Diol B chain extenders and the prepolymer is more amorphous than crystalline in character, which allows for a greater degree of phase mixing between the formed amorphous hard segment and the soft segment of the polyurethane elastomers. These phenomena can also be evidenced from the observation of higher glass transition temperatures (Tg) determined by the DMA analysis as well as the clearer appearances of the cast urethane elastomeric materials.

Figures 8 and 9 show the pot life of cast elastomers made with Baytec ME-050 (Figure 8) and Baytec MS-242 (Figure 9) extended with either HQEE or Diol D. Since the Diol D elastomer can be processed at a lower temperature, the rate of reaction was reduced thereby resulting in a greater pot life.

While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of invention which is to be given the full breadth of the claims appended and any and all equivalents thereof.