Two-component spray flexible polyurethane foam system

Abstract

A two-component spray flexible polyurethane foam system includes an isocyanate component including a polymeric isocyanate present in an amount between about 40 percent and about 50 percent by weight and a resin component reactive with and separate from the isocyanate component. The resin component includes a polyether polyol having a weight average molecular weight of between about 4000 and about 7000 grams per mole present in an amount between about 40 and about 55 percent by weight. The resin component also includes a blowing agent and an alkyl triol present in an amount between about 0.1 and about 0.5 percent by weight to delay foaming by at least one second. The resin component further includes a diorganotin dilauryl mercaptide present in an amount between about 0.005 and about 0.05 percent by weight to catalyze foaming within at most five seconds.

Description

TWO-COMPONENT SPRAY FLEXIBLE POLYURETHANE FOAM SYSTEMBACKGROUND OF THE INVENTION1. Field of the Invention

[0001] The invention relates generally to a two-component spray flexible polyurethane foam system.2. Description of the Related Art

[0002] Two-component spray polyurethane foam systems commonly include an isocyanate component and a resin component reactive with the isocyanate component. The isocyanate component and the resin component are typically kept separate from one another until the reaction is desired to occur. Conventional two-component spray polyurethane foam systems also typically include a blowing agent such that a foam reaction product forms from the reaction of the isocyanate component and the resin component. The isocyanate component, the resin component, and the blowing agent are fed through a nozzle and sprayed upon a substrate to be coated. Commonly, the substrate is supported to permit the isocyanate component, the resin component, and the blowing agent to be sprayed upward onto a bottom of the substrate. However, there is typically a delay after contact of the isocyanate component, the resin component, and the blowing agent before the reaction occurs and the foam reaction product forms. During this delay, the isocyanate component and the resin component may drip from the bottom of the substrate, either preventing complete coating of the bottom of the substrate or forming stalactites which hang from the bottom of the substrate. To attempt to combat these drips, a primer is commonly applied to the bottom of the substrate. However, the primer adds additional cost and processing time, and still fails to completely prevent drips.

[0003] As such, there remains a need for an improved two-component spray polyurethane foam system.SUMMARY OF THE INVENTION AND ADVANTAGES

[0004] A two-component spray flexible polyurethane foam system includes an isocyanate component and a resin component reactive with and separate from the isocyanate component. The isocyanate component includes a polymeric isocyanate present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system. The resin component includes a polyether polyol having a weight average molecular weight of between about 4000 and about 7000 grams per mole present in an amount between about 40 and about 55 percent by weight of the spray flexible polyurethane foam system. The resin component also includes a blowing agent and an alkyl triol present in an amount between about 0.1 and about 0.5 percent by weight of the spray flexible polyurethane foam system such that the alkyl triol is sufficient to delay foaming by at least one second after contact of the isocyanate component and the resin component. The resin component further includes a diorganotin dilauryl mercaptide present in an amount between about 0.005 and about 0.05 percent by weight of the spray flexible polyurethane foam system such that the diorganotin dilauryl mercaptide is sufficient to catalyze foaming within at most five seconds after contact of the isocyanate component and the resin component.

[0005] The alkyl triol is present in an amount between about 0.1 and about 0.5 percent by weight of the spray flexible polyurethane foam system such that the alkyl triol is sufficient to delay foaming by at least one second after contact of the isocyanate component and the resin component, thereby permitting the two-component spray flexible polyurethane foamsystem to be sprayed onto an entire surface of a substrate without being inhibited by premature formation of a foam reaction product of the isocyanate component and the resin component which blocks surfaces of the substrate from being sprayed. Moreover, the fact that the diorganotin dilauryl mercaptide is present in an amount sufficient to catalyze foaming within at most five seconds after contact of the isocyanate component and the resin component prevents drips which either result in incomplete coating of the substrate or allow formation of stalactites.DETAILED DESCRIPTION OF THE INVENTION

[0006] A two-component spray flexible polyurethane foam system is able to be applied to a substate, including to a vehicle and particularly a vehicle undercarriage of a vehicle, to form a foam reaction product. The two-component spray flexible polyurethane foam system includes an isocyanate component and a resin component reactive with and separate from the isocyanate component. The isocyanate component includes a polymeric isocyanate present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system. The resin component includes a polyether polyol having a weight average molecular weight of between about 4000 and about 7000 grams per mole present in an amount between about 40 and about 55 percent by weight of the spray flexible polyurethane foam system. The resin component also includes a blowing agent and an alkyl triol present in an amount between about 0.1 and about 0.5 percent by weight of the spray flexible polyurethane foam system such that the alkyl triol is sufficient to delay foaming by at least one second after contact of the isocyanate component and the resin component. The resin component further includes a diorganotin dilauryl mercaptide present in an amount between about 0.005 and about0.05 percent by weight of the spray flexible polyurethane foam system such that the diorganotindilauryl mercaptide is sufficient to catalyze foaming within at most five seconds after contact of the isocyanate component and the resin component.

[0007] The alkyl triol is present in an amount between about 0.1 and about 0.5 percent by weight of the spray flexible polyurethane foam system such that the alkyl triol is sufficient to delay foaming by at least one second after contact of the isocyanate component and the resin component, thereby permitting the two-component spray flexible polyurethane foam system to be sprayed onto an entire surface of a substrate without being inhibited by premature formation of the foam reaction product of the isocyanate component and the resin component which blocks surfaces of the substrate from being sprayed. Moreover, the fact that the diorganotin dilauryl mercaptide is present in an amount sufficient to catalyze foaming within at most five seconds after contact of the isocyanate component and the resin component prevents drips which either result in incomplete coating of the substrate or allow formation of stalactites.

[0008] Although not required, the diorganotin dilauryl mercaptide may include a dialkyltin dilauryl mercaptide. As non-limiting examples, the dialkyltin dilauryl mercaptide may include dimethyltin dilauryl mercaptide, dibutyltin dilauryl mercaptide, and / or dioctyltin dilauryl mercaptide. Other dialkyltin dilauryl mercaptides not specifically recited above are contemplated in the subject description. As such, it is to be appreciated that the diorganotin dilauryl mercaptide may include dimethyltin dilauryl mercaptide, dibutyltin dilauryl mercaptide, and / or dioctyltin dilauryl mercaptide. Dimethyltin dilauryl mercaptide, dibutyltin dilauryl mercaptide, and dioctyltin dilauryl mercaptide are all suitable to assist formation of the foam reaction product and all have high hydrolytic stability as compared to catalysts with other anions, for example, catalysts with oxides, thioglycolates, and carboxylates. Hydrolytic stability is a measure of a chemical’s capacity to withstand and resist chemical decomposition when exposed to water. As such,hydrolytic stability of the dialkyltin dilauryl mercaptide is particularly important when the blowing component is water. Although all dialkyltin dilauryl mercaptides have high hydrolytic stability, it is to be appreciated that dioctyltin dilauryl mercaptide has the highest hydrolytic stability as compared to dibutyltin dilauryl mercaptide and dimethyltin dilauryl mercaptide. Dibutyltin dilauryl mercaptide has a hydrolytic stability between that of dioctyltin dilauryl mercaptide and dimethyltin dilauryl mercaptide. Additionally, dimethyltin has the relatively lowest hydrolytic stability as compared to dioctyltin dilauryl mercaptide and dibutyltin dilauryl mercaptide.

[0009] Dimethyltin dilauryl mercaptide has the highest endcure catalytic activity as compared to dibutyltin dilauryl mercaptide and dioctyltin dilauryl mercaptide. Dibutyltin dilauryl mercaptide has an endcure catalytic activity between that of dimethyltin dilauryl mercaptide and dioctyltin dilauryl mercaptide. Dioctyltin dilauryl mercaptide has the relative lowest hydrolytic stability as compared to dimethyltin dilauryl mercaptide and dibutyltin dilauryl mercaptide.

[0010] The dialkyltin dilauryl mercaptide may also consist essentially of dimethytin dilauryl mercaptide. It is to be appreciated that the dialkyltin dilauryl mercaptide may consist essentially of dimethyltin dilauryl mercaptide and still include an amount of dibutyltin dilauryl mercaptide and dioctyltin dilauryl mercaptide, for example to increase the hydrolytic stability of the dialkyltin dilauryl mercaptide, should the primary endcure catalytic activity of the dialkyltin dilauryl mercaptide be resultant from the dimethyltin dilauryl mercaptide. It is to be appreciated that the primary purpose of the dialkyltin dilauryl mercaptide is to function as a blow catalyst. As such, the endcure catalytic activity is the primary consideration in determining which particular dialkyl dilauryl mercaptide to include and the hydrolytic stability, while still an important formulation concern, is a secondary consideration in determining which particulardialkyl dilauryl mercaptide to include. The dialkyltin dilauryl mercaptide may even consist of dimethyltin dilauryl mercaptide. It is to be appreciated that the dialkyltin dilauryl mercaptide may be dimethyltin dilauryl mercaptide.

[0011] More specifically, the dimethyltin dilauryl mercaptide may be between about 0.005 and about 0.05 percent by weight of the spray flexible polyurethane foam system. It is also to be appreciated that dimethyltin dilauryl mercaptide present in an amount between 0.005 and about 0.05 percent by weight of the spray flexible polyurethane foam system is sufficient to catalyze foaming within at most five seconds after contact of the isocyanate component and the resin component. Moreover, the dimethyltin dilauryl mercaptide may be between about 0.01 and about 0.03 percent by weight of the spray flexible polyurethane foam system. The dimethyltin dilauryl mercaptide may also be about 0.02 percent by weight of the spray flexible polyurethane foam system.

[0012] Dimethyltin dilauryl mercaptide has very high hydrolytic stability and provides for fast gelification, fast cure speed, and reduction of the tack time of the two-component spray flexible polyurethane foam system. The dimethyltin dilauryl mercaptide may be Fomrez UL- 22 from Galata Chemicals.

[0013] Additionally, the alkyl triol may include glycerin. The alkyl triol may also consist essentially of glycerin. The alkyl triol may even consist of glycerin. It is to be appreciated that the alkyl triol may be glycerin. More specifically, the alkyl triol may be between about 0.1 and about 0.5 percent by weight of the spray flexible polyurethane foam system. It is also to be appreciated that glycerin present in an amount between about 0.1 and about 0.5 percent by weight of the spray flexible polyurethane foam system is sufficient to delay foaming by at least one second after contact of the isocyanate component and the resin component. Moreover, the glycerin maybe between about 0.2 and about 0.4 percent by weight of the spray flexible polyurethane foam system. The glycerin may also be about 0.3 percent by weight of the spray flexible polyurethane foam system. More specifically, the glycerin may be about 0.32 percent by weight of the spray flexible polyurethane foam system. Glycerin participates in the reaction between the isocyanate component and the resin component. The glycerin may act as a cross-linker.

[0014] The resin component of the spray flexible polyurethane foam system advantageously may particularly include both dimethyltin dilauryl mercaptide and glycerin. The combination of dimethyltin dilauryl mercaptide and glycerin in the resin component greatly improves adhesiveness (e.g. to the substrate being sprayed) of an uncured reaction product of the resin component and the isocyanate component formed prior to curing. The improved adhesiveness of the uncured reaction product of the resin component and the isocyanate component formed prior to curing permits the uncured reaction product to coat surfaces of a substrate without dripping, thus permitting complete coating of the substrate and preventing formation of stalactites.

[0015] Although not required, the resin component may further include a gel catalyst. The gel catalyst may include a tertiary amine present in an amount between about 0.85 and about 1.6 percent by weight of the spray flexible polyurethane foam system. The tertiary amine may include at least one chosen from triethylene diamine and 2-dimethylaminoethanol. In other words, the tertiary amine may include triethylene diamine, may include 2-dimethylaminoethanol, or may include both triethylene diamine and 2-dimethylaminoethanol. The tertiary amine may include triethylene diamine present in an amount between about 0.05 and about 0.4 percent by weight of the spray flexible polyurethane foam system. More particularly, the tertiary amine may include triethylene diamine present in an amount between about 0.1 and about 0.3 percent by weight of the spray flexible polyurethane foam system, present in an amount between about 0.1and about 0.2 percent by weight of the spray flexible polyurethane foam system, or about 0.15 percent by weight of the spray flexible polyurethane foam system. The triethylene diamine may be TEGOAMIN 33LV from Evonik. The tertiary amine may also include 2-dimethylaminoethanol present in an amount between about 0.8 and about 1.2 percent by weight of the spray flexible polyurethane foam system. More specifically, the tertiary amine may include 2- dimethylaminoethanol present in an amount between 0.9 and about 1.1 percent by weight of the spray flexible polyurethane foam system, or about 1.0 percent by weight of the spray flexible polyurethane foam system. The tertiary amine may be Tegoamin DMEA from Evonik.

[0016] The polymeric isocyanate may include at least two chosen from 2,2’- diphenyl methane diisocyanate, 2,4’-diphenyl methane diisocyanate, and 4,4’-diphenyl methane diisocyanate together present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system. In other words, the polymeric isocyanate may include 2,2’-diphenyl methane diisocyanate and 2,4’-diphenyl methane diisocyanate together present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system, may include 2,2’-diphenyl methane diisocyanate and 4,4’-diphenyl methane diisocyanate together present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system, may include 2,4’ -diphenyl methane diisocyanate and 4,4 ’-diphenyl methane diisocyanate together present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system, or may include 2,2’ -diphenyl methane diisocyanate, 2,4’ -diphenyl methane diisocyanate, and 4,4’- diphenyl methane diisocyanate together present in an amount between about 40 percent and about 50 percent by weight of the spray flexible polyurethane foam system.

[0017] More specifically, polymeric isocyanate may include 4,4’-diphenyl methane diisocyanate present in an amount between about 25 and about 35 percent by weight of the spray flexible polyurethane foam system, between about 28 and about 33 percent by weight of the spray flexible polyurethane foam system, between about 30 and about 32 percent by weight of the spray flexible polyurethane foam system, or about 31 percent by weight of the spray flexible polyurethane foam system. The 4,4’ -diphenyl methane diisocyanate may include a determined content of isomers and highly functionalized homologues. The polymeric isocyanate may include 2,4’ -diphenyl methane diisocyanate present in an amount between about 10 and about 15 percent by weight of the spray flexible polyurethane foam system, between about 11 and about 14 percent by weight of the spray flexible polyurethane foam system, between about 12 and about 13 percent by weight of the spray flexible polyurethane foam system, or about 12.5 percent by weight of the spray flexible polyurethane foam system. The polymeric isocyanate may further include 2,2’- diphenyl methane diisocyanate present in an amount between about 0.1 and about 0.3 percent by weight of the spray flexible polyurethane foam system, or about 0.2 percent by weight of the spray flexible polyurethane foam system. The polymeric isocyanate may include one, or both, of Desmodur 44V20 and Desmodur VPPU 0129M from Covestro.

[0018] First polyether polyol comprising one or more polyether chains extending from the residue of glycerin

[0019] The polyether polyol may include at least two chosen from a first polyether polyol having an ethylene-oxide propylene-oxide copolymer glycerol ether, a second polyether polyol having copolymerized styrene and acrylonitrile, and a third polyether polyol modified with ethylene oxide. In other words, the polyether polyol may include the first polyether polyol having the ethylene-oxide propylene-oxide copolymer glycerol ether and the second polyether polyolhaving copolymerized styrene and acrylonitrile, the first polyether polyol having the ethyleneoxide propylene-oxide copolymer glycerol ether and the third polyether polyol modified with ethylene oxide, the second polyether polyol having copolymerized styrene and acrylonitrile and the third polyether polyol modified with ethylene oxide, or the first polyether polyol having the ethylene-oxide propylene-oxide copolymer glycerol ether, the second polyether polyol having copolymerized styrene and acrylonitrile, and the third polyether polyol modified with ethylene oxide.

[0020] The at least two chosen from a first polyether polyol having the ethyleneoxide propylene-oxide copolymer glycerol ether, the second polyether polyol having copolymerized styrene and acrylonitrile, and the third polyether polyol modified with ethylene oxide may include the first polyether polyol having the ethylene-oxide propylene-oxide copolymer glycerol ether. In other words, the polyether polyol may include the first poly ether polyol having the ethylene-oxide propylene-oxide copolymer glycerol ether and at least one chosen from the second polyether polyol having copolymerized styrene and acrylonitrile and the third polyether polyol modified with ethylene oxide.

[0021] The at least two chosen from the first polyether polyol having the ethylene- oxide propylene-oxide copolymer glycerol ether, the second polyether polyol having copolymerized styrene and acrylonitrile, and the third polyether polyol modified with ethylene oxide may include the second polyether polyol having copolymerized styrene and acrylonitrile. In other words, the polyether polyol may include the second polyether polyol having copolymerized styrene and acrylonitrile and at least one chosen from the first polyether polyol having the ethylene-oxide propylene-oxide copolymer glycerol ether and the third polyether polyol modified with ethylene oxide.

[0022] The at least two chosen from the first polyether polyol having the ethyleneoxide propylene-oxide copolymer glycerol ether, the second polyether polyol having copolymerized styrene and acrylonitrile, and the third polyether polyol modified with ethylene oxide may include the third polyether polyol modified with ethylene oxide. In other words, the polyether polyol may include the third polyether polyol modified with ethylene oxide and at least one chosen from the first polyether polyol having the ethylene-oxide propylene-oxide copolymer glycerol ether and the second polyether polyol having copolymerized styrene and acrylonitrile.

[0023] The first polyether polyol may be present in an amount between about 30 and about 40 percent by weight of the spray flexible polyurethane foam system, between about 32 and about 39 percent by weight of the spray flexible polyurethane foam system, between about 34 and about 38 percent by weight of the spray flexible polyurethane foam system, between about 35 and about 37 percent by weight of the spray flexible polyurethane foam system, or about 36 percent by weight of the spray flexible polyurethane foam system. The first polyether polyol may have a nominal molecular weight of about 6000 grams per mol. The first polyether polyol may particularly be Voranol 4701 from Dow.

[0024] The second polyether polyol may be present in an amount between about 6 and about 12 percent by weight of the spray flexible polyurethane foam system, between about 7 percent and about 11 percent by weight of the spray flexible polyurethane foam system, between about 8 and about 10 percent by weight of the spray flexible polyurethane foam system, or about 9 percent by weight of the spray flexible polyurethane foam system. The second polyether polyol may be a copolymeric polyol including a stable dispersion of styrene and acrylonitrile. The second polyether polyol may also include ethylene oxide -propylene oxide copolymer glycerol. The secondpolyether polyol may further include 2-propenenitrile with ethnylbenzene and 2-methyloxirane. The second polyether polyol may particularly be SPECFLEX NC 701 from Dow.

[0025] The third polyether polyol may be present in an amount between about 1 and about 3 percent by weight of the spray flexible polyurethane foam system, between about 1 and about 2 percent by weight of the spray flexible polyurethane foam system, or may be about 1.5 percent by weight of the spray flexible polyurethane foam system. The third poly ether polyol may have a nominal molecular weight of 4550 grams per mole. The third polyether polyol may particularly be Multranol 9199 MX from Covestro.

[0026] The resin component may further include a surfactant. The surfactant may include a phthalate-free organosiloxane present in an amount between about 0.05 and about 0.4 percent by weight of the spray flexible polyurethane foam system. It is to be appreciated that the phthalate-free organosiloxane is free of phthalates. Moreover, the phthalate-free organosiloxane may be present in an amount between about 0.1 and about 0.3 percent by weight of the spray flexible polyurethane foam system, or about 0.2 percent by weight of the spray flexible polyurethane foam system. The phthalate-free organosiloxane assists in regulating a critical zone which is close to the surface of the foam reaction product of the isocyanate component and the resin component. More particularly, the phthalate-free organosiloxane prevents an undesirably wide cell size distribution in the critical zone near the surface of the foam reaction product. The phthalate-free organosiloxane may particularly be Tegostab B 8715 from Evonik.

[0027] The resin component may further include a flame retardant. The flame retardant includes tris-(2-chloroisopropyl) phosphate present in an amount between about 0.5 and about 3 percent by weight of the spray flexible polyurethane foam system. Moreover, the tris-(2- chloroisopropyl) phosphate may be present in an amount between about 0.8 and about 2 percentby weight of the spray flexible polyurethane foam system, between about 1.0 and about 1.6 percent by weight of the spray flexible polyurethane foam system, between about 1.2 and about 1.5 percent by weight of the spray flexible polyurethane foam system, between about 1.3 and about 1.4 percent by weight of the spray flexible polyurethane foam system, or about 1.36 percent by weight of the spray flexible polyurethane foam system. The tris-(2-chloroisopropyl) phosphate may particularly be POLY TCCP-LO from Polyorganic Tecnologia.

[0028] The resin component may further include an amine cross-linker. The amine- cross linker may have diethanol amine and triethanol amine. The amine cross-linker may be between about 0.7 and about 1.1 percent by weight of the spray flexible polyurethane foam system. More specifically, the amine-cross linker may be between about 0.8 and about 1.0 percent by weight of the spray flexible polyurethane foam system, or about 0.9 percent by weight of the spray flexible polyurethane foam system. The amine-cross linker may have diethanol amine present in an amount between about 0.08 and about 0.2 percent by weight of the spray flexible polyurethane foam system, between about 0.09 and about 0.15 percent by weight of the spray flexible polyurethane foam system, or about 0.1 percent by weight of the spray flexible polyurethane foam system. The amine-cross linker may have triethanol amine present in an amount between about 0.6 and about 1.0 percent by weight of the spray flexible polyurethane foam system, between about 0.7 and about 0.9 percent by weight of the spray flexible polyurethane foam system, or about 0.8 percent by weight of the spray flexible polyurethane foam system. The amine-cross linker may include one, or both, of DEOA LF 85 and TEOA 85 from Evonik.

[0029] Although not required, the resin component may further include a pigment. In a non-limiting example, the resin component may include the pigment present in an amount between about 0.5 and 1.5 percent by weight of the spray flexible polyurethane foam system,between about 0.7 and about 1.2 percent by weight of the spray flexible polyurethane foam system, between about 0.8 and about 1.0 percent by weight of the spray flexible polyurethane foam system, or about 0.9 percent by weight of the spray flexible polyurethane foam system. The pigment may be a black pigment, and particularly may be Black Repitan 99553 from Repi.

[0030] Additionally, although not required, the blowing agent may be water. The water may be present in an amount between about 2 and about 4 percent by weight of the spray flexible polyurethane foam system, between about 2.5 and about 3 percent by weight of the spray flexible polyurethane foam system, or about 2.7 percent by weight of the spray flexible polyurethane foam system.

[0031] The spray flexible polyurethane foam system may be configured to begin foaming between about 2 seconds and about 4 seconds after contact of the isocyanate component and the resin component. The spray flexible polyurethane foam system being configured to begin foaming between about 2 second and about 4 seconds after contact of the isocyanate component and the resin component limits drips when the spray flexible polyurethane foam system is applied to a substrate, permitting the spray flexible polyurethane foam system to fully coat the substrate without formation of stalactites. The inclusion of dimethyltin dilauryl mercaptide in the resin component may assist in configuring the spray flexible polyurethane foam system to begin foaming between about 2 seconds and about 4 seconds after contact of the isocyanate component and the resin component.

[0032] The spray flexible polyurethane foam system may be configured to cure within at most about 200 seconds after contact of the isocyanate component and the resin component. Once cured, the isocyanate component and the resin component have ceased to further react. It is to be appreciated that the reaction between the isocyanate component and the resincomponent is visible as evidenced by foaming of the foam reaction product. Once foaming ceases, the reaction between the isocyanate component and the resin component has ceased. Such a quick curing time further assists in preventing drips and formation of stalactites.

[0033] The foam reaction product of the isocyanate component and the resin component may be closed cell and non-absorbent to water. As such, the foam reaction product may be particularly suitable for use on substrates which require being sealed from the environment. In other words, the foam reaction product may be a sealant. The foam reaction product may also be flexible and / or compressive. As such, the foam reaction product may be able to bend, and thus may be suitable for use on substrates which are subject to motion, particularly which are subject to vibration and / or harshness.

[0034] As mentioned herein, the vehicle includes the vehicle undercarriage. As a non-limiting example, the foam reaction product of the isocyanate component and the resin component of the spray flexible polyurethane foam system may be applied to the vehicle undercarriage to seal the vehicle undercarriage from moisture. The foam reaction product applied to the vehicle undercarriage is particularly advantageous when closed cell and non-absorbent to water to seal the vehicle undercarriage from moisture present in the environment (e.g. on a road). The foam reaction product applied to the vehicle undercarriage is also particularly advantageous when flexible and / or compressive so that the foam reaction product is able to bend in response to vibration and / or harshness (e.g. resultant from the vehicle driving down the road).

[0035] Although not required, the vehicle may be free of a primer between the vehicle undercarriage and the foam reaction product of the isocyanate component and the resin component of the spray flexible polyurethane foam system. The high adhesiveness of the uncured reaction product of the isocyanate component and the resin component permits the spray flexiblepolyurethane foam system to adhere to the vehicle undercarriage without the use of a primer. The vehicle undercarriage being free of a primer decreases the manufacturing time required to seal the undercarriage of the vehicle by completely removing a typically required processing step. Moreover, the vehicle undercarriage being free of a primer reduces the cost necessary to seal the vehicle undercarriage.

[0036] As described herein, the resin component of the spray flexible polyurethane foam system advantageously may particularly include both dimethyltin dilauryl mercaptide and glycerin. The combination of dimethyltin dilauryl mercaptide and glycerin in the resin component greatly improves adhesiveness (e.g., to the vehicle undercarriage) of an uncured reaction product of the resin component and the isocyanate component formed prior to curing. The improved adhesiveness of the uncured reaction product of the resin component and the isocyanate component formed prior to curing permits the uncured reaction product to coat the undercarriage of the vehicle without the use of a primer and without dripping, thus allowing a quick and inexpensive solution to sealing the vehicle undercarriage while still permitting complete coating of the vehicle undercarriage without the formation of stalactites.

[0037] The following examples are intended to illustrate the present disclosure and is not to be read in any way as limiting to the scope of the present disclosure.Example 1

[0038] Example 1 is of a spray flexible polyurethane foam system according to the teachings of the present disclosure. The spray flexible polyurethane foam system has an isocyanate component including a polymeric isocyanate and a resin component reactive with and separate from the isocyanate component. The isocyanate component includes polymeric 4,4 ’-diphenyl methane diisocyanate present in an amount of about 32 percent by weight of the spray flexiblepolyurethane foam system, polymeric 2,4 ’-diphenyl methane diisocyanate present in an amount of about 12 percent by weight of the spray flexible polyurethane foam system, and 2,2 ’-diphenyl methane diisocyanate present in an amount of about 1 percent by weight of the spray flexible polyurethane foam system.

[0039] The resin component of the spray flexible polyurethane foam system of Example 1 includes the first polyether polyol, the second polyether polyol, and the third polyether polyol as described herein. The first polyether polyol is present in an amount of about 36.4 percent by weight of the spray flexible polyurethane foam system, the second polyether polyol is present in an amount of about 9.1 percent by weight of the spray flexible polyurethane foam system, and the third polyether polyol is present in an amount of about 1.6 percent by weight of the spray flexible polyurethane foam system.

[0040] The resin component of the spray flexible polyurethane foam system of Example 1 includes glycerin present in an amount of about 0.3 percent by weight of the spray flexible polyurethane foam system and dimethyltin dilauryl mercaptide present in an amount of about 0.02 percent by weight of the spray flexible polyurethane foam system. The resin component of the spray flexible polyurethane foam system of Example 1 also includes tris(2-chloroisopropyl) phosphate present in an amount of about 1.4 percent by weight of the spray flexible polyurethane foam system. The resin component of the spray flexible polyurethane foam system of Example 1 further includes the phthalate-free organosiloxane present in an amount of about 0.2 percent by weight of the spray flexible polyurethane foam system.

[0041] The resin component of the spray flexible polyurethane foam system of Example 1 further includes an amine cross-linker, particularly diethanol amine present in an amount of about 0.2 percent by weight of the spray flexible polyurethane foam system andtriethanolamine present in an amount of about 0.8 percent by weight of the spray flexible polyurethane foam system. The resin component of the spray flexible polyurethane foam system of Example 1 further includes a gel catalyst, particularly triethylene diamine present in an amount of about 0.2 percent by weight of the spray flexible polyurethane foam system and 2- dimethylaminoethanol present in an amount of about 1 percent by weight of the spray flexible polyurethane foam system.

[0042] The resin component of the spray flexible polyurethane foam system of Example 1 further includes black pigment present in an amount of about 0.9 percent by weight of the spray flexible polyurethane foam system. The resin component of the spray flexible polyurethane foam system of Example 1 further includes water as a blowing agent. The remainder of the spray flexible polyurethane foam is water.Example 2

[0043] Example 2 is of a vehicle including a vehicle undercarriage. A foam reaction product of the isocyanate component and the resin component of the spray flexible polyurethane foam system of Example 1 is applied to the vehicle undercarriage to seal the vehicle undercarriage from moisture. The foam reaction product applied to the vehicle undercarriage is closed celled and non-absorbent to water to seal the vehicle undercarriage from moisture present in the environment (e.g. on a road). The foam reaction product applied to the vehicle undercarriage is flexible and compressive so that the foam reaction product is able to bend in response to vibration and harshness (e.g. resultant from the vehicle driving down the road).

[0044] The vehicle of Example 2 is free of a primer between the vehicle undercarriage and the foam reaction product. As described herein, the resin component of the spray flexible polyurethane advantageously includes both dimethyltin dilauryl mercaptide and glycerin.The combination of dimethyltin dilauryl mercaptide and glycerin in the resin component greatly improved adhesiveness to the vehicle undercarriage of an uncured reaction product of the resin component and the isocyanate component formed prior to curing. The improved adhesiveness of the uncured reaction product of the resin component and the isocyanate component formed prior to curing permitted the uncured reaction product to coat the undercarriage of the vehicle without the use of a primer and without dripping. The vehicle undercarriage was thus completely coated without the formation of stalactites and thereby sealed.

[0045] The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings, and the invention may be practiced otherwise than as specifically described.

Claims

CLAIMSWhat is claimed is:

1. A two-component spray flexible polyurethane foam system comprising: an isocyanate component comprising a polymeric isocyanate present in an amount between about 40 percent and about 50 percent by weight of said spray flexible polyurethane foam system; and a resin component reactive with and separate from said isocyanate component, said resin component comprising: polyether polyol having a weight average molecular weight of between about 4000 and about 7000 grams per mole and present in an amount between about 40 and about 55 percent by weight of said spray flexible polyurethane foam system; a blowing agent; an alkyl triol present in an amount between about 0.1 and about 0.5 percent by weight of said spray flexible polyurethane foam system such that said alkyl triol is sufficient to delay foaming by at least one second after contact of said isocyanate component and said resin component; and a diorganotin dilauryl mercaptide present in an amount between about 0.005 and about 0.05 percent by weight of said spray flexible polyurethane foam system such that said diaorganotin dilauryl mercaptide is sufficient to catalyze foaming within at most five seconds after contact of said isocyanate component and said resin component.

2. The spray flexible polyurethane foam system as set forth in claim 1 , wherein said diorganotin dilauryl mercaptide comprises dimethyltin dilauryl mercaptide.

3. The spray flexible polyurethane foam system as set forth in claim 1, wherein said diorganotin dilauryl mercaptide consists essentially of dimethyltin dilauryl mercaptide.

4. The spray flexible polyurethane foam system as set forth in any one of claims 2 and 3, wherein said dimethyltin dilauryl mercaptide is between about 0.01 and about 0.03 percent by weight of said spray flexible polyurethane foam system.

5. The spray flexible polyurethane foam system as set forth in any one of claims 1-4, wherein said alkyl triol consists essentially of glycerin.

6. The spray flexible polyurethane foam system as set forth in claim 5, wherein said glycerin is between about 0.2 and about 0.4 percent by weight of said spray flexible polyurethane foam system.

7. The spray flexible polyurethane foam system as set forth in any one of claims 1-6, wherein said resin component further comprises a gel catalyst comprising a tertiary amine present in an amount between about 0.85 and about 1.6 percent by weight of said spray flexible polyurethane foam system, wherein said tertiary amine comprises at least one chosen from triethylene diamine and 2-dimethylaminoethanol.

8. The spray flexible polyurethane foam system as set forth in claim 7, wherein said tertiary amine comprises triethylene diamine present in an amount between about 0.05 and about 0.4 percent by weight of said spray flexible polyurethane foam system.

9. The spray flexible polyurethane foam system as set forth in any one of claims 7 and 8, wherein said tertiary amine comprises 2-dimethylaminoethanol present in an amount between about 0.8 and about 1.2 percent by weight of said spray flexible polyurethane foam system.

10. The spray flexible polyurethane foam system as set forth in any one of claims 1-9, wherein said polymeric isocyanate comprises at least two chosen from 2,2 ’-diphenyl methanediisocyanate, 2,4’-diphenyl methane diisocyanate, and 4,4’-diphenyl methane diisocyanate together present in an amount between about 40 percent and about 50 percent by weight of said spray flexible polyurethane foam system.

11. The spray flexible polyurethane foam system as set forth in any one of claims 1-10, wherein said polyether polyol comprises at least two chosen from a first polyether polyol having an ethylene-oxide propylene-oxide copolymer glycerol ether, a second polyether polyol having copolymerized styrene and acrylonitrile, and a third polyether polyol modified with ethylene oxide.

12. The spray flexible polyurethane foam system as set forth in any one of claims 1-10, wherein said polyether polyol comprises a first polyether polyol having an ethylene-oxide propylene-oxide copolymer glycerol ether, a second polyether polyol having copolymerized styrene and acrylonitrile, and a third polyether polyol modified with ethylene oxide.

13. The spray flexible polyurethane foam system as set forth in any one of claims 1-12, wherein said resin component further comprises a surfactant comprising a phthalate-free organosiloxane present in an amount between about 0.05 and about 0.4 percent by weight of said spray flexible polyurethane foam system.

14. The spray flexible polyurethane foam system as set forth in any one of claims 1-13, wherein said resin component further comprises a flame retardant comprising tris-(2- chloroisopropyl) phosphate present in an amount between about 0.5 and about 3 percent by weight of said spray flexible polyurethane foam system.

15. The spray flexible polyurethane foam system as set forth in any one of claims 1-14, wherein said resin component further comprises an amine cross-linker having diethanol amine andtriethanol amine, wherein said amine cross-linker is between about 0.7 and about 1.1 percent by weight of said spray flexible polyurethane foam system.

16. The spray flexible polyurethane foam system as set forth in any one of claims 1-15, wherein a foam reaction product of said isocyanate component and said resin component is closed cell and non-absorbent to water.

17. The spray flexible polyurethane foam system as set forth in any one of claims 1-16, wherein said spray flexible polyurethane foam system is configured to begin foaming between about 2 seconds and about 4 seconds after contact of said isocyanate component and said resin component.

18. The spray flexible polyurethane foam system as set forth in any one of claims 1-17, wherein said spray flexible polyurethane foam system is configured to cure within at most about 200 seconds after contact of said isocyanate component and said resin component.

19. A vehicle comprising, a vehicle undercarriage, and a foam reaction product of said isocyanate component and said resin component of said spray flexible polyurethane foam system as set forth in any one of claims 1-18 applied to said vehicle undercarriage to seal said vehicle undercarriage from moisture.

20. The vehicle as set forth in claim 19, wherein said vehicle is free of a primer between said vehicle undercarriage and said foam reaction product of said isocyanate component and said resin component of said spray flexible polyurethane foam system.