Field of Disclosure

This disclosure relates to a polyurethane textile backing and methods for preparing the polyurethane textile backing.

Background

Polyurethane can be used in the production of textiles to form backings on textiles. For example, in the production of carpeting, a polyurethane backing can adhere a pile of the carpeting to a primary backing of the carpeting. By adhering the pile to the primary backing with the polyurethane, the dimensional stability of the carpeting can be increased, thus preventing the pile from becoming detached from the primary backing when the textile is subjected to stress, heat, and/or moisture, for example.

Preparation and application of the polyurethane can be performed with equipment that has limitations associated with application and curing of the polyurethane. This equipment can be large and expensive to manufacture, which prompts polyurethane compositions to be formulated around equipment limitations. In an example, during preparation and application, polyurethane is present within the equipment for a particular residence time and thus presents limitations associated with formulation of the polyurethane. For instance, premature gelation of the polyurethane should be avoided so the polyurethane remains workable within the equipment during preparation and application. If premature gelation occurs, difficulties can ensue with regards to preparation and application of the polyurethane.

In addition, upon application, the polyurethane can be cured by applying heat to the polyurethane for a particular amount of time in a curing stage. This can be accomplished by passing the textile with the polyurethane backing under a heat source to cure the polyurethane. Upon completion of the curing stage, a strong cure should be obtained.

One way to obtain properties of the polyurethane that are requisite for

preparation, application, and curing of the polyurethane is through use of a catalyst with the polyurethane reaction components (e.g., polyol, polyisocyanate). Use of a catalyst with the polyurethane reaction components can provide for an increased time in which the reaction mixture retains a viscosity low enough for preparation and application (e.g., an increased pot life) and also can provide for a strong cure in the curing stage.

However, challenges can arise with use of some catalysts because they do not provide both a sufficient pot life and/or a strong cure for use with a polyurethane textile backing. In addition, some catalysts that do provide a strong cure and increased pot life for polyurethane backings can be associated with environmental concerns. Therefore, it is desirable to improve upon the selection of catalysts for use with polyurethane textile backings.

Summary

Embodiments of the present disclosure include a method for preparing a polyurethane textile backing that is particularly suited to processing conditions used to produce textiles with polyurethane backings. For example, the polyurethane textile backing provides a strong cure at temperatures that will not cause heat related damage to the textile. In addition, the polyurethane textile backing can provide an increased pot life that allows for preparation and application of the polyurethane textile backing without premature gelation.

The method includes admixing a polyol, a polyisocyanate, and a catalyst. The catalyst can be selected from the group consisting of a chelated zinc carboxylate, a chelated bismuth carboxylate or a combination thereof. The admixture is applied to a textile and cured at a temperature in a range of from 60 degrees Celsius (°C) to 135 °C to form the polyurethane textile backing on the textile. The textile can be a woven textile, a non-woven textile, a tufted textile or a combination thereof, and can be formed from a poly olefin, a poly amide, a polyester or a combination thereof.

The present disclosure also provides for a polyurethane textile backing formed from the reaction of a polyisocyanate, a polyol, and a catalyst. The polyisocyanate has an isocyanate group (NCO) content of 10 to 45 weight percent NCO (wt.% NCO) and is present in an amount to provide for an isocyanate reaction index of from 85 to 130. The polyol has a number average molecular weight of from 800 to 4,000. The catalyst is selected from the group consisting of a chelated zinc carboxylate, a chelated bismuth carboxylate or a combination thereof and is present in an amount of from 0.01 to 1.0 parts by weight (PB ) per 100 PBW of the polyol.

The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The description that follows more particularly exemplifies illustrative embodiments. In several places throughout the application, guidance is provided through lists of examples, which examples can be used in various combinations. In each instance, the recited list serves only as a representative group and should not be interpreted as an exclusive list, Detailed Description

Embodiments of the present disclosure provide a method for preparing a polyurethane textile backing with an increased pot life. As used herein "pot life" refers to a time in which the reaction mixture retains a viscosity low enough for preparation and application. In an example, this value is quantified as a viscosity of 20,000 centipoise, measured at 27 °C and atmospheric pressure. The increase in pot life allows for a longer time for preparation and/or application of the polyurethane textile backing. In addition, the increase in pot life allows for a delayed gelation of the polyurethane textile backing, thus allowing the reaction mixture forming the polyurethane textile backing to maintain a lower viscosity over a period of time.

The lower viscosity can allow the polyurethane textile backing to be spread more evenly over the textile. In an example, the polyurethane textile backing can be applied with a knife coating system. For instance, knife coating systems can deposit a puddle of the polyurethane textile backing on the textile and spread the puddle with a knife. As such, the knife coating system can spread the lower viscosity puddle more evenly since premature gelation of the polyurethane textile backing does not occur.

In addition, the lower viscosity of the polyurethane textile backing can cause less stress on components in the application system. In an example, the lower viscosity can allow the polyurethane textile backing to flow more easily through the application system. For instance, the lower viscosity can allow the polyurethane textile backing to be pumped more easily, saving additional wear and electricity costs associated with pumps in the application system. Embodiments of the present disclosure provide a polyurethane textile backing with a decreased cure time. In an example, upon application of the polyurethane textile backing to the textile, the polyurethane can be cured by applying heat to the polyurethane for a particular time in a curing stage. Generally, it is desirable that this time be minimized to match the speed at which textiles are processed. Accordingly, the polyurethane textile backing can provide a decreased cure time that is compatible with the speeds at which textiles are processed.

In addition, the decreased cure time associated with the polyurethane textile backing can be attained at a temperature that does not cause thermal deformation of heat sensitive materials. For example, textiles can be made from heat sensitive materials such as polyethylene, which can have low melting points relative to other materials that are used in textiles. The polyurethane textile backing of the present disclosure can be applied to these heat sensitive materials and cured at a temperature that will not cause thermal deformation of the textile.

As provided herein, the method for preparing a polyurethane textile backing includes admixing a polyol, a polyisocyanate, and a catalyst. Polyols are members of a family of polymers that contain terminal hydroxy 1 groups and can be either polyethers or polyesters, for example.

Polyether polyols can be produced by reacting either amines or materials having terminal hydroxyl groups with alkylene oxides using a catalyst. Examples of polyether polyols include, but are not limited to those sold under the trade designator,

VORANOL™ polyols (The Dow Chemical Company), VORANOL™ VORACTIV™ polyols (The Dow Chemical Company), hydroxylated soybean oil polyols, propoxylated and/or ethoxylated glycerol polyols, ethoxylated and/or propoxylated sorbitol polyols, propoxylated and/or ethoxylated glycols, ethoxylated and/or propoxylated sucrose polyols, amine-initiated polyols such as propoxylated ethylenedi amine polyols, propoxylated/ethoxylated ethylenediamine polyols, toluenediamine

propoxylated/ethoxylated polyols, and toluenediamine propoxylated polyols.

Polyester polyols can be produced by reacting either diacids or terephthalates with glycols having terminal hydroxyl groups using a catalyst. Diacids can include, but are not limited to, adipic acid, for example. Glycol sources can include, but are not limited to, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerine, and 1,4-butanediol, among others. Examples of polyester polyols can include

DIOREZ™ polyester polyols, available from The Dow Chemical Company.

The polyol can have an average functionality within a range of from 2 to 8, preferably within a range of from 2 to 3. The polyol can have a number average molecular weight of from 800 to 4,000, preferably within a range of from 1,000 to 3,000. In addition, the polyol can have a number average molecular weight of 2,000. The number average molecular weight can be determined based on analysis of the hydroxyl end groups of the polyol.

The polyisocyanate can include aromatic, aliphatic, and cycloaliphatic isocyanates. The isocyanate group of the polyisocyanate combines with the hydroxyl group of the polyol to form a urethane linkage. Preferred isocyanates have an average functionality within the range of 2 to 8, preferably within the range of 2 to 5. Examples of polyisocyanates include, but are not limited to, methylene diphenyl diisocyanate (MDI), such as ISONATE ^® PR 7594 (The Dow Chemical Company), polymeric methylene diphenyl diisocyanate (PMDI), a MDI prepolymer, a PMDI prepolymer, a carbodiimide modified MDI, a uretonimine modified MDI or a combination thereof.

Use of a catalyst can speed the reaction of the isocyanate group of the

polyisocyanate with the hydroxyl group of the polyol, which can otherwise be slow. As such, the cure time associated with the polyurethane textile backing can be increased, providing compatibility with increased speed of processing of the textile.

The catalyst can be a chelated metal carboxylate. A chelate is a complex ion in which a metal ion is bonded to two or more atoms of a chelating agent. Some organic acids, including an organic acid selected from the group of oxalic acid, citric acid, acetic acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid, ethyIeneglycol-bis(beta- aminoethyl ether)-N,N-tetraacetic acid or a combination thereof, have a chelating capacity and can be considered chelating agents. Chelated metal ions, or chelate formation, can occur when a solution that includes a chelating agent, such as an organic acid or amine, contacts a metal ion.

Examples of the chelated metal carboxylate can include, but are not limited to, a chelated zinc carboxylate, a chelated bismuth carboxylate or a combination thereof. Examples of chelated zinc carboxylates that are commercially available include, but are not limited to, those sold under the trade designator K-Kat XK-614 (King Industries).

The method for preparing the polyurethane textile backing of the present disclosure can also, optionally, include admixing a co-catalyst with the polyol, polyisocyanate, and the catalyst. In some embodiments, the co-catalyst can be activated by heat. For example, in the absence of heat, the co-catalyst can provide for a delayed initiation of the urethane (polyol-isocyanate) reaction. This can help provide an admixture, which includes the co-catalyst, with an increased pot life, because the urethane reaction is delayed. However, upon application of heat to the admixture, which includes the co-catalyst, the urethane reaction can be promoted by the co-catalyst, thus providing a reduced cure time that is compatible with the speed of processing.

In some embodiments, the co-catalyst can be a tertiary amine. Examples of the tertiary amine include, but are not limited to, l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (Air Products), DBU blocked with 2-ethylhexanoic acid (Air Products) or a combination thereof. In particular, DBU blocked with 2-ethylhexanoic acid can provide for a further delay in the urethane reaction, thus providing an increase in pot life.

The method includes applying the admixture of the polyol, polyisocyanate, and catalyst to the textile. In some embodiments, a "B" component can be formed of the polyol and all other components, besides the polyisocyanate. The B component and the polyisocyanate can then be admixed at a frothing mix head, which can be configured to mix the B component and the polyisocyanate mechanically through baffles and/or by injecting a blowing agent gas into the frothing mix head, for example, an Oakes Frother (E.T. Oakes Corporation). Examples of the blowing agent include, but are not limited to, air, nitrogen, carbon dioxide or a combination thereof.

The admixture can then be applied to the textile. Examples of the textile can include, but are not limited to, woven textiles, non-woven textiles, tufted textiles or a combination thereof. The textile can be formed from a poly olefin, a poly amide, a polyester or a combination thereof. The polyurethane textile backing can provide benefits when used as a backing on textiles made from poly olefin. For instance, the polyurethane textile backing can be cured at a temperature that is below the melting point of a polyolefin, thus avoiding deformation of the textile. As such, embodiments of the present disclosure allow for polyurethane textile backings to be applied to textiles made from heat sensitive materials.

In some embodiments, the admixture can be applied to the textile using a doctor blade, air knife, or extruder to apply and gauge the layer of the admixture. Alternatively, the polyurethane can be applied by depositing the admixture onto a moving belt and allowing it to partially cure, before marrying it to the textile using equipment such as a double belt laminator, for example.

Upon application of the admixture to the textile, the admixture can be cured to obtain the polyurethane textile backing. The admixture can be cured by applying heat from a heat source (e.g., open flame oven, infrared oven). The admixture can be cured at a cure temperature in a range of from 60 °C to 135 °C to form the polyurethane textile backing on the textile. All individual values and subranges from 60 °C to 135 °C are included; for example, the cure temperature can be a lower limit of 60 °C, 70 °C, or 85 °C to an upper limit of 100 °C, 120 °C, or 135 °C. Specific examples include a cure temperature in a range from 60 °C to 100 °C, 60 °C to 120 °C , 70 °C to 100 °C, 70 °C to 120 °C, 70 °C to 135 °C, 85 °C to 100 °C, 85 °C to 120 °C, and 85 °C to 135 °C.

Upon preparation and application of the admixture, water can be introduced into the admixture, which can cause detrimental effects associated with curing the admixture. Water can be introduced through moisture in the air, condensation in the equipment, and/or through fillers that are admixed into the admixture, for example. Introduction of water in the admixture can affect performance of the catalyst and/or co-catalyst, resulting in an incomplete cure of the polyurethane textile backing. In some embodiments, the method can include removing the water from the admixture through the addition of a molecular sieve. Examples of the molecular sieve include, but are not limited to, zeolite.

As provided herein, embodiments of the present disclosure include a

polyurethane textile backing formed from the reaction of the polyisocyanate, the polyol, and the catalyst. The polyisocyanate includes isocyanate groups that react with hydroxyl groups of the polyol in a urethane reaction to form the polyurethane textile backing of the present disclosure.

As discussed herein, examples of the polyisocyanate include, but are not limited to, methylene diphenyl diisocyanate (MDI), such as ISONATE ^® PR 7594 (The Dow Chemical Company), polymeric methylene diphenyl diisocyanate (PMDI), a MDI prepolymer, a PMDI prepolymer, a carbodiimide modified MDI, a uretonimine modified MDI, toluene diisocyanate (TDI) or a combination thereof.

The polyisocyanate can have an isocyanate group (NCO) content of 10 to 45 weight percent wt. % NCO. All individual values and subranges from 10 wt. % NCO to 45 wt. % NCO are included; for example, the wt. % NCO can be a lower limit of 10 wt. % NCO, 20 wt. % NCO, or 25 wt. % NCO to an upper limit of 35 wt. % NCO, 40 wt. % NCO, or 45 wt. % NCO. Specific examples include a wt. % NCO in a range of from 10 wt. % NCO to 25 wt. % NCO, 10 wt. % NCO to 40 wt. % NCO, 20 wt. % NCO to 35 wt. % NCO, 20 wt. % NCO to 40 wt. % NCO, 20 wt. % NCO to 45 wt. % NCO, 25 wt. % NCO to 35 wt. % NCO, 25 wt. % NCO to 40 wt. % NCO, and 25 wt. % NCO to 45 wt. % NCO. In addition, the NCO content of the polyisocyanate can be 27.5 wt. %.

For the preparation of a polyurethane textile backing, the polyisocyanate is present in an amount, relative to the polyol, so as to provide an isocyanate reaction index from 85 to 130, preferably from 100 to 115. In addition, the isocyanate reaction index can be 110. An isocyanate reaction index of 100 corresponds to one isocyanate equivalent per active hydroxyl group present in the polyol composition. Accordingly, if the isocyanate reaction index is 115, there is a 15% excess of isocyanate groups to hydroxyl groups, and if the isocyanate reaction index is 85, there is a 15% deficit of isocyanate groups to hydroxyl groups.

For the various embodiments, the polyol has a number average molecular of 800 to 4,000. All individual values and subranges from 800 to 4,000 are included; for example, the number average molecular weight can be from a lower limit of 800 or 1,000 to an upper limit of 3,000 or 4,000. Specific examples include a number average molecular of the polyol from 800 to 3,000, 1,000 to 3,000, and 1,000 to 4,000.

The polyurethane textile backing of the present disclosure speeds the rate of reaction of the isocyanate group and the hydroxyl group of the polyol through use of a catalyst. Examples of the catalyst include, but are not limited to, a chelated zinc carboxylate, a chelated bismuth carboxylate or a combination thereof.

The catalyst can be present in an amount from 0.01 PBW per 100 PBW of the polyol to 1.0 PBW per 100 PBW of the polyol. All individual values and subranges from 0.01 PBW per 100 PBW of the polyol to 1.0 PBW per 100 PBW of the polyol are included; for example, the polyurethane textile backing can include an amount of catalyst from a lower limit of 0.01 PBW per 100 PBW of the polyol, 0.05 PBW per 100 PBW of the polyol, 0.075 PBW per 100 PBW of the polyol, or 0.1 PBW per 100 PBW of the polyol to an upper limit of 0.45 PBW per 100 PBW of the polyol, 0.75 PBW per 100 PBW of the polyol, or 1.0 PBW per 100 PBW of the polyol. Specific examples include a polyurethane textile backing with catalyst present in an amount from 0.01 PBW per 100 PBW of the polyol to 0.45 PBW per 100 PBW of the polyol, 0.01 PBW per 100 PBW of the polyol to 0.75 PBW per 100 PBW of the polyol, 0.05 PBW per 100 PBW of the polyol to 0.45 PBW per 100 PBW of the polyol, 0.05 PBW per 100 PBW of the polyol to 0.75 PBW per 100 PBW of the polyol, 0.05 PBW per 100 PBW of the polyol to 1.0 PBW per 100 PBW of the polyol, 0.075 PBW per 100 PBW of the polyol to 0.45 PBW per 100 PBW of the polyol, 0.075 PBW per 100 PBW of the polyol to 0.75 PBW per 100 PBW of the polyol, 0.075 PBW per 100 PBW of the polyol to 1.0 PBW per 100 PBW of the polyol, 0.1 PBW per 100 PBW of the polyol to 0.45 PBW per 100 PBW of the polyol, 0.1 PBW per 100 PBW of the polyol to 0.75 PBW per 100 PBW of the polyol, and 0.1 PBW per 100 PBW of the polyol to 1.0 PBW per 100 PBW of the polyol.

For one or more embodiments, the polyol can include a chain extender and/or cross-linker. The chain extender and/or cross-linker can tie the polymer chains together into a polymer network, for example. Suitable chain extenders and/or cross-linkers that can be used in the polyol mixture include organic compounds having an equivalent weight of less than 500. These compounds can be selected from hydroxyl terminated and amine terminated compounds or a combination thereof.

Preferably, the chain extender can be present in a range of 2 to 20 PBW of the chain extender per 100 PBW of the polyol. Examples of the chain extender can include, but are not limited to, 1,4-butanediol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, diethyltoluenediamine, dimethylthiotoluenediamine or a combination thereof. In addition, the polyol can include 15 PBW of a chain extender per 100 PBW of the polyol.

Preferably, the cross-linker can be present in a range of 1 to 10 PBW of the cross- linker per 100 PBW of the polyol. Examples of the cross-linker can include, but are not limited to, glycerol, trimethylol propane, diethanolamine, triethanolamine or a combination thereof.

For one or more embodiments, the polyurethane textile backing can include a filler, which can allow for substitution of part of the polymeric agents and also confer dimensional stability and hardness to the polyurethane textile backing. Examples of fillers can include, but are not limited to, calcium carbonate, alumina trihydrate, coal fly ash, barium sulfate, antimony trioxide, talc, bentonite, kaolin, barite, barium sulfate, gypsum or a combination thereof.

The filler can be present in an amount from 50 parts per 100 PBW of the polyol to 600 parts per 100 PBW of the polyol, depending on filler type and particle size distribution. All individual values and subranges from 50 parts per 100 PBW of the polyol to 600 parts per 100 PBW of the polyol are included; for example, the

polyurethane textile backing can include a filler from a lower limit of 50 parts per 100 PBW of the polyol, 100 parts per 100 PBW of the polyol, or 190 parts per 100 PBW of the polyol to an upper limit of 210 parts per 100 PBW of the polyol, 220 parts per 100 PBW of the polyol, or 600 parts per 100 PBW of the polyol. Specific examples include a polyurethane textile backing with filler present in an amount from 50 parts per 100 PBW of the polyol to 210 parts per 100 PBW of the polyol, 100 parts per 100 PBW of the polyol to 210 parts per 100 PBW of the polyol, 190 parts per 100 PBW of the polyol to 210 parts per 100 PBW of the polyol, 50 parts per 100 PBW of the polyol to 220 parts per 100 PBW of the polyol, 100 parts per 100 PBW of the polyol to 220 parts per 100 PBW of the polyol, 190 parts per 100 PBW of the polyol to 220 parts per 100 PBW of the polyol, 100 parts per 100 PBW of the polyol to 600 parts per 100 PBW of the polyol, and 190 parts per 100 PBW of the polyol to 600 parts per 100 PBW of the polyol. In addition the polyurethane textile backing can include 200 PBW of the filler per 100 PBW of the polyol.

The amount of filler can be adjusted to accommodate economic and rheological requirements. As the amount of filler approaches 200 parts per 100 PBW of the polyol, an increase in dimensional stability and hardness is noticed with the polyurethane textile backing. So the embodiments of the present disclosure allow for some control over the dimensional stability and hardness of the polyurethane textile backing. As discussed herein, water can be introduced into the polyurethane textile backing through the filler, affecting performance of the catalyst and/or co-catalyst, resulting in incomplete cure of the polyurethane textile backing. Accordingly, water can be removed from the polyurethane textile backing through use of a molecular sieve. Examples of the molecular sieve can include, but are not limited to, zeolite, aluminosilicate or a combination thereof.

The polyurethane textile backing can be applied to textiles formed from a polyolefin (e.g., polyethylene), a polyamide (e.g., polyamide 6, polyamide 6,6), a polyester (e.g., polyethylene terephthalate), and/or combinations thereof. As discussed herein, the polyurethane textile backing of the present disclosure can be applied to heat sensitive materials and cured at a temperature that is less than the melting point of the material that forms the textile, thus preventing deformation of the textile.

Examples

The following examples are given to illustrate, but not limit, the scope of this disclosure. Unless otherwise indicated, percentages are by weight. Weight percent is the percentage of one compound included in a total mixture, based on weight. The weight percent can be determined by dividing the weight of one component by the total weight of the mixture and then multiplying by 100. Unless otherwise specified, all instruments and chemicals used are commercially available.

The following procedure exemplifies a standard procedure for making the chelated zinc carboxylate catalyst, the chelated bismuth carboxylate catalyst, and the polyurethane textile backing and measuring the pot life and tack free time of the resulting polyurethane textile backing. In addition, one skilled in the art will appreciate that this is an exemplary procedure and that other components can be substituted or removed in the procedure to make the chelated zinc carboxylate catalyst, the chelated bismuth carboxylate catalyst, and the polyurethane textile backing.

Materials

BiCAT ^® 8210 (Bismuth 2-ethylhexanoate, The Shepherd Chemical Company),

BiCAT ^® 3228 (Co-catalyst, Zinc 2-ethylhexanoate, The Shepherd Chemical Company), BiCAT V (Co-catalyst, blend of bismuth neodecanoate and bismuth 2-ethyIhexanoate, The Shepherd Chemical Company), VORANOL ^® 9287A (Polyol, 2,000 number average molecular weight, Ethylene oxide-capped diol, The Dow Chemical Company),

VORANOL ^® 9120 A (Polyol, 2,000 number average molecular weight, The Dow

Chemical Company), JEFFAMINE ^® D230 (Huntsman), Dipropylene glycol (Chain extender, Dow Chemical), Calcium Carbonate (Filler, Imerys), Molecular sieve (Type 3 A powder, UOP), ISONATE ^® PR 7594 modified Methylene diphenyl diisocyanate

(Polyisocyanate, 27.5 wt.% NCO, The Dow Chemical Company), K-KAT ^® XK-614 in VORANOL 9281 A polyol (Chelated zinc carboxylate, King Industries), POLYCAT ^® DBU (Co-catalyst, l,8-Diazabicyclo[5.4.0]undec-7-ene (DBU), Air Products), IPDA (Isophorone diamine, (BASF)), TOYOCAT ^® DB-30 (Co-catalyst, 1,2,4 triazol, TOSO USA).

Preparation of a Chelated Zinc Carboxylate (CATALYST 1)

Add 5.0 g of BiCAT ^® 3228 and 39.4 g of VORANOL ^® 9287A to a plastic beaker.

Stir the mixture at room temperature (23 °C) with a wooden spatula for 1 minute. Add 5.6 g of JEFFAMINE ^® D230 to the mixture and stir the mixture with the wooden spatula for 1 minute at room temperature. BiCAT ^® 3228 contains excess 2-ethylhexanoic acid, therefore, the amount of JEFFAMINE ^® D230 added was determined to give a nitrogen to zinc ratio of 2:1 and also account for the excess 2-ethylhexanoic acid.

Allow the mixture to sit for 24 hours until the mixture changes in color from clear to milky white.

Preparation of a Chelated Bismuth Carboxylate (CATALYST 2)

Add 5.0 g of BiCAT ^® 8210 and 40.0 g of VORANOL® 9287A to a plastic beaker. Stir the mixture at room temperature with a stainless steel spatula for 1 minute. Add 5.0 g of IPDA to the mixture and stir the mixture with the stainless steel spatula for 1 minute at room temperature. BiCAT ^® 8210 contains excess 2-ethylhexanoic acid, therefore, the amount of IPDA added was determined to give a nitrogen to zinc ratio of 4.5: 1 and also account for the excess 2-ethylhexanoic acid. Initially, the mixture formed a clear solution, but after 1 minute of stirring the viscosity increased to form a paste-like consistency.

Preparation of Filled Polyol Compound

Add 85 PBW of VO ANOL ^® 9120A and 15 PBW of dipropylene glycol to a container to obtain 100 PBW of polyol. 100 parts polyol is taken as combination of 85 PBW VORANOL ^® 9120A and 15 PBW glycol. Add 200 PBW of calcium carbonate filler per 100 PBW of the polyol and 5 PBW of molecular sieve per 100 PBW of the polyol. Stir the mixture at room temperature with a 2 inch diameter Cowles-type mixer at 2,000 revolutions per minute (RPM) for one minute until the filler is completely dispersed into the polyol to form the filled polyol compound.

Equipment

Viscosity

A Brookfield viscometer (model RVDV-II+) was used to measure changes in viscosity. The viscometer was calibrated by an accredited instrument maintenance firm using appropriate calibration procedures. In obtaining data from the viscometer, a #7 spindle and 9 ounce waxed paper cup (Solo Cup Co.) were used and the speed control was set to 20 RPM. A thermocouple was inserted into the cup to obtain a temperature for each test.

Tack free time

Equipment used in measuring the tack-free time includes a piece of substrate that is formed from a woven fiberglass impregnated with Teflon ^® , a wooden tongue depressor and an oven.

Comparative Examples A, B, C, and D

Prepare comparative Examples A, B, and C (containing non-chelated metal catalysts, the filled polyol compound, and the polyisocyanate) as follows.

Comparative Example A Add ISONATE ^® PR 7594 modified methylene diphenyl diisocyanate to the filled polyol compound in an amount relative to the filled polyol compound to provide for an isocyanate (NCO) reaction index of 110. The NCO reaction index can be calculated through the equation:

No. of equivalents of NCO

NCO reaction index = ~ :— : — :——— x 100

No. of equivalents of polyol OH

Stir the mixture with the 2-inch diameter Cowles-type mixer at 1500 rpm until the mixture reaches a temperature of 26.7 °C. Add 0.08 PBW of dibutyltin sulfide per 100

PBW of the polyol to the mixture and record the time as T=0. Stir the mixture for an additional 30 seconds.

Determination of Pot Life

The viscosity of the mixture was measured as a function of time using the

Brookfield viscometer (model RVDV-II+) and the #7 spindle at a speed of 20 rpm. The time, from T=0, to the time when the viscosity reaches 20,000 centipoise (cP), a value which is used to quantify pot life.

Determination of Tack Free Time

Deposit 20 to 50 grams of the mixture on a piece of substrate. Place the piece of substrate in an oven heated to 85 °C and/or 120 °C. Probe the mixture every 15 seconds with a wooden tongue depressor to check whether the mixture adheres to the depressor, using a new tongue depressor each time. Record the time, from T=0, to the time when no material in the mixture adheres to a wooden tongue depressor when the depressor is removed from the sample, a value used to quantify tack free time.

Comparative Example B

Prepare Comparative Example B using the same method as Comparative Example

A except, rather than adding dibutyltin sulfide, add 0.05 PBW of BiCAT ^® 3228 (Zinc 2- efhylhexanoate) per 100 PBW of the polyol.

Comparative Example C

Prepare Comparative Example C using the same method as Comparative Example

A except, rather than adding dibutyltin sulfide, add 0.05 PBW of BiCAT ^® 8210 (Bismuth

2-ethylhexanoate) per 100 PBW of the polyol. Comparative Example D

Prepare Comparative Example D using the same method as Comparative Example A except, rather than adding dibutyltin sulfide, add 0.01 PBW of BiCAT ^® 8210 per 100 PBW of the polyol.

Comparative Example E

Prepare Comparative Example D using the same method as Comparative Example A except, rather than adding dibutyltin sulfide, add 0.023 PBW of BiCAT ^® V per 100 PBW of the polyol and add 0.306 PBW of TOYOCAT ^® DB-30 per 100 PBW of the polyol.

Table I

The data in Table I shows that the use of BiCAT 3228 in Comparative Example B provides a decreased pot life time and a similar time to reach tack free state versus use of dibutyltin sulfide in Comparative Example A. Comparative Examples C and D show BiCAT ^® 8210 is more catalytic than Comparative Examples A or B. Comparative Example D demonstrates that a low use level of BiCAT ^® 8210 provides an increased pot life time, but also provides an increased time to reach tack free state. The use of BiCAT V with a co-catalyst of TOYOCAT ^® DB-30 in Comparative Example E provides a decreased time to reach tack free state at a lower temperature of 85°C, but has a decreased pot life versus use of dibutyltin sulfide in Comparative Example A.

Examples 1 to 5

Prepare examples 1 to 5 (containing chelated zinc catalysts, the filled polyol compound, and the polyisocyanate) as follows.

Example 1

Prepare Example 1 using the same method as Comparative Example A except, rather than adding dibutyltin sulfide, add 0.05 PBW of CATALYST 1 per 100 PBW of the polyol.

Example 2

Prepare Example 2 using the same method as Comparative Example A except, rather than adding dibutyltin sulfide, add 0.1 PBW of K-Kat® XK-614 per 100 PBW of the polyol.

Example 3

Prepare Example 3 using the same method as Example 2 except, rather than adding 0.1 PBW of K-KAT® XK-614 per 100 PBW of the polyol, add 0.05 PBW of K- KAT® XK-614 per 100 PBW of the polyol and add 0.05 PBW of POLYCAT® DBU per 100 PBW of the polyol.

Example 4

Prepare Example 4 using the same method as Example 3 except, rather than adding 0.05 PBW of K-KAT® XK-614 per 100 PBW of the polyol and adding 0.05 PBW of POLYCAT® DBU per 100 PBW of the polyol, add 0.075 PBW of K-KAT® XK-614 per 100 PBW of the polyol and add 0.075 PBW of POLYCAT® DBU per 100 PBW of the polyol.

Example 5

Prepare Example 5 using the same method as Example 4 except, rather than adding 0.075 PBW of K-KAT® XK-614 per 100 PBW of the polyol and adding 0.075 PBW of POLYCAT® DBU per 100 PBW of the polyol, add 0.1 PBW of K-KAT® XK- 614 per 100 PBW of the polyol and add 0.1 PBW of POLYCAT® DBU per 100 PBW of the polyol. Table II

The data in Table II shows that use of CATALYST 1 in Example 1, which has been chelated, offers an increased time to reach 20,000 cP over Comparative Example B, which has a catalyst that has not been chelated. The data in Table II also shows that Catalyst 1 has the same time to reach a tack free state as the non-chelated catalyst in Comparative Example B. In addition, data from Table II shows that with addition of a DBU co-catalyst, an increase in time to reach 20,000 cP and the same or decreased time to reach tack free state can be achieved over Comparative Example A and B.

Examples 6 to 9

Prepare examples 6 to 9 (containing chelated bismuth catalysts, the filled polyol compound, and the polyisocyanate) as follows.

Example 6

Prepare Example 6 using the same method as Comparative Example A except, rather than adding dibutyltin sulfide, add 0.01 PBW of CATALYST 2 per 100 PBW of the polyol.

Example 7

Prepare Example 7 using the same method as Example 6 except, add 0.45 PBW of POLYCAT ^® DBU per 100 PBW of the polyol. Example 8

Prepare Example 8 using the same method as Example 7 except, rather than adding 0.45 PBW of CATALYST 2 per 100 PBW of the polyol, add 0.01 PBW of CATALYST 2 per 100 PBW of the polyol and add 0.05 PBW of POLYCAT ^® DBU per 100 PBW of the polyol.

Example 9

Prepare Example 9 using the same method as Example 8 except, rather than adding 0.01 PBW of CATALYST 2 per 100 PBW of the polyol and adding 0.05 PBW of POLYCAT ^® DBU per 100 PBW of the polyol, add 0.015 PBW of CATALYST 2 per 1 0 PBW of the polyol and add 0.075 PBW of POLYCAT ^® DBU per 100 PBW of the polyol. Example 10

Prepare Example 10 using the same method as Example 9 except, rather than adding 0.015 PBW of CATALYST 2 per 100 PBW of the polyol and adding 0.075 PBW of POLYCAT ^® DBU per 100 PBW of the polyol, add 0.02 PBW of CATALYST 2 per 100 PBW of the polyol and add 0.10 PBW of POLYCAT ^® DBU per 100 PBW of the polyol.

Example 11

Prepare Example 11 using the same method as Example 10 except, rather than adding 0.02 PBW of CATALYST 2 per 100 PBW of the polyol and adding 0.10 PBW of POLYCAT ^® DBU per 100 PBW of the polyol, add 0.10 PBW of CATALYST 2 per 100 PBW of the polyol and add 0.05 PBW of POLYCAT ^® DBU per 100 PBW of the polyol. Example 12

Prepare Example 12 using the same method as Example 11 except, rather than adding 0.10 PBW of CATALYST 2 per 100 PBW of the polyol and adding 0.05 PBW of POLYCAT ^® DBU per 100 PBW of the polyol, add 0.15 PBW of CATALYST 2 per 100 PBW of the polyol and add 0.075 PBW of POLYCAT ^® DBU per 100 PBW of the polyol. Example 13

Prepare Example 13 using the same method as Example 12 except, rather than adding 0.075 PBW of POLYCAT ^® DBU per 100 PBW of the polyol, add 0.10 PBW of POLYCAT ^® DBU per 100 PBW of the polyol. Example 14

Prepare Example 14 using the same method as Example 13 except, rather than adding 0.15 PBW of CATALYST 2 per 100 PBW, add 0.25 PBW of CATALYST 2 per 100 PBW of the polyol.

Table III

POLYCAT ^® 0.10

DBU

The data in Table III shows that use of CATALYST 2 in Example 6, which has been chelated, offers an increased time to reach 20,000 cP over Comparative Examples A to E, which have a catalyst that has not been chelated. Examples 8 through 14 demonstrate that the levels of CATALYST 2 and POLYCAT DBU co-catalyst can be adjusted to give a time to reach tack free state that is equivalent to Comparative Example A, even at a lower cure temperature than Comparative Example A, and still have an increased time to reach 20,000 cP versus Comparative Example A.