Bisphenol a free vinyl ester compositions suitable for cured-in-place pipe potable water applications

Abstract

Styrene-free and bisphenol A free vinyl ester compositions are herein reported. These compositions provide good physical and mechanical performance while eliminating the use of potentially hazardous substances. The resin systems are designed to minimize or remove the capacity for any harmful substance to leach out of the final composite part. Specifically, this invention targets the development of resin systems that are suitable for the repair of sewer and potable water pipe systems as part of a cured-in-place pipe application. In general, these compositions showcase vinyl ester compositions free of bisphenol-a without compromising the utility and performance of such.

Description

TITLE OF THE INVENTION

[0001] Bisphenol A Free Vinyl Ester Compositions Suitable for Cured-In-Place Pipe Potable Water ApplicationsCROSS REFERENCE TO RELATED APPLICATIONS

[0002] The This application derives priority from U.S. Provisional Patent Application No. 63 / 573,862. filed 3 Apri l 2024, the entirety of which is incorporated herein by reference.BACKGROUND OF THE INVENTION

[0003] Field of the Invention

[0004] The present invention pertains to styrene-free and bisphenol-a (BPA) free vinyl ester compositions. In a more specific illustration, this invention relates to the use of said vinyl ester compositions for cured-in-place pipe applications or tank relining. Similarly, this invention also relates to a process for the manufacture of these resin compositions.

[0005] Description of the Background

[0006] Bisphenol- A (BPA) is a ubiquitous chemical found in a plethora of consumer applications ranging from food storage containers to water bottles, epoxy resins and many others. This substance has received significant attention in toxicological research, and the ensuing regulatory framework reflects that the material is a significantly toxic one. At this juncture, it is well established that BPA is endocrine disruptor capable of creating neurological, reproductive, and cardiovascular diseases, among others. Many of the uses of BPA constitute a potential case for exposure to the chemical due to its ability to leach out of the products containing it. Thus, ithas become evident that BPA usage needs to be curtailed or eliminated out of certain applications.

[0007] Moreover, BPA has recently been identified as an environmental contaminant of emerging concern. It is well established that this substance is readily present in waterways, soil, and even the air. Currently, most BPA consumption is driven by the production of polycarbonates, which accounts for 65-70% of BPA's production. Meanwhile, epoxy resins and vinyl ester resins account for almost all of the remaining bal ance, at around 25-30%. It is thus of paramount importance that alternatives to BPA be found expeditiously.

[0008] Some of the existing applications for BPA are those in which there could potentially be contamination of a water supply, such as cured-in-place pipe (CIPP).

[0009] CIPP is the preferred way to rehabilitate pipe systems nowadays due to the ease of installation and the avoidance of the removal of old piping systems. Currently, a great deal of pipe systems are rehabilitated using epoxy and vinyl ester resins, particularly those used to transport potable water. Since most commercially available vinyl esters are derived from BPA, it has become imperative to create materials to displace these compositions. However, any resins used for CIPP applications must be capable of curing under both thermal and photoinitiation strategies. In addition, resins usable in CIPP applications must have the ability to impregnate felt and glass fibers, or a combination of fabric and glass fiber, as these are widely-used reinforcements rvithin the CIPP industry. The resulting composite part must possess excellent mechanical performance which is comparable (or better), in terms of performance, to existing vinyl esters resins which are derived from BPA.

[0010] Separately, another component of prior art CIPP systems which has come under scrutiny in recent years is the reactive diluent used to dissolve the resins used in prior art CIPP systems:styrene. In recent years, styrene has come under scrutiny due to its potential carcinogenic and genotoxic potential. Thus, a CIPP system that does not use styrene as a reactive diluent would be an improvement over the prior art.

[0011] In addition, certain prior art systems utilize various components which include or are comprised of small molecules, such as the reaction catalyst or the curing moieties. hi prior art systems, small molecules have been shown to leach out of the finished CIPP system, and in CIPP systems which are used for potable water applications, into the water supply. However, these materials may not be suitable to for human exposure. Many of these substances could represent harmful components for the environment as well. Therefore, a CIPP system which reduces the risk of leaching from the cured composite part would also be an improvement over the prior art.

[0012] In U.S. Patent Application Publication No., 2021 / 03807444, Miller et.al. disclosed compositions of BPA-containing vinyl ester resins and separate unsaturated polyester resins with reduced leaching capacity. The main strategy used to achieve these results was the use of multifunctional (meth)-acrylates in combination with a reactive synthesis catalyst. However, the Miller publication still suffered from the drawback that the disclosed compounds included BPA.SUMMARY OF THE INVENTION

[0013] The present invention is a series of new bisphenol- A free vinyl ester compositions for use within cured-in-place-pipe (CIPP) potable water applications. The present invention includes a series of styrene-free and BPA-free thermosetting resin compositions made from a vinyl ester alkyd, a reactive catalyst and multifunctional (meth)-acrylates monomers. As used herein, the term (meth)-acrylates refers to reactive diluents such as acrylates and methacrylate. Unlike prior art vinyl esters, these novel vinyl ester compositions eliminate the use of BPA whilesimultaneously preventing the leaching of hazardous substances from the fully cured composite part. In addition, these thermosetting compositions are capable of curing under both thermal catalysis and photo-irradiation conditions. The vinyl ester compositions here disclosed contain a multi functional (meth)-acrylate with a functionality factor equal or larger than two reactive units per molecule. It is reasonable to state that the use of the selected monomers has a direct influence on the capacity for the finished product to leach any substance to the environment at levels that would be considered hazardous.

[0014] Accordingly, an object of this invention is to provide styrene-free and BPA-free vinyl ester compositions with mechanical and physical properties suitable for use in cured-in-place pipe relining and / or tank relining.

[0015] Another object of this invention is to provide compositions capable of been cured using either thermal- or photoinitiation.

[0016] Another object of this invention is to provide vinyl ester resin composition synthesized with a multifunctional catalyst capable of subsequently reacting during the composite curing process.

[0017] Another object of this invention is to provide styrene-free and bisphenol A-free vinyl ester resin compositions with multifunctional reactive diluents.

[0018] Another object of this invention is to provide thermosetting resin composition capable of preventing the leaching of hazardous substances into the environment.

[0019] These and other objects, features and advantages of this invention will become apparent from the following detailed description.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] To address the shortcomings of the prior art, noted above, the present inventors have discovered novel vinyl ester compositions that will folly eliminate any exposure to BPA or BPA- derived materials within the CIPP industry. The inventive compositions follow the reaction of aliphatic-, bisphenol F-, novo lac- and resorcinol-derived epoxy diglycidyl ethers with (metisacrylic acid in combination with a reactive catalyst to yield a series of novel vinyl esters. Subsequently, these novel vinyl esters are diluted using multifunctional (meth)-acrylates which further increase the crosslinked density of the cured materials. Therefore, there is reduced leaching potential of any other species out of the cured thermoset material. In addition, the disclosed novel vinyl ester resin compositions fully eliminate the use of styrene. This will provide a way to create piping systems capable of supporting the safe transportation of potable water and eliminate known environmental concerns.

[0021] The inventive compositions have been tested for both heat- and U V-cured CIPP applications and, in both cases, it has been found that in fact, these are all suitable candidates for the CIPP industry. More so, several of the developed compositions exceed the parameters established by the industry.

[0022] This invention can be further illustrated by the following examples of certain embodiments. Although it will be understood that these examples are included merely for purposes of illustration and are not intended to limit the scope of this invention unless otherwise specifically indicated.

[0023] In one embodiment, the present invention provides a curable resin composition, comprising:(a) a BPA free vinyl ester in an amount of 40-90% by weight, based on the total weight of the composition;(b) a (meth)-acrylate diluent having 2 or more reactive moieties; and(c) a synthesis catalyst which contains at least one reactive double bond and its capable of catalyzing the vinyl ester reaction and subsequently reacting to become part of the composite part.

[0024] As noted above, in some preferred embodiments, the amount of BPA free vinyl ester in composition is in the range of 40-90% by weight, whereby the amount of (meth)-acrylate diluent in the composition may be in the range of 10-60% by weight, all based on the weight of components (a) - (c). In other preferred embodiments, the amount of BPA free vinyl ester in composition is in the range of 80-90% by weight, and the amount of (meth)-acrylate diluent in the composition is in the range of 10-20% by weight, all based on the weight of components (a) - (e).

[0025] In the compositions of the invention as set forth above, the total amount of components (a), (b), and (c) shall equal 100 weight percent. As defined above, component (c) is used as a catalyst in the reaction between the diglycidyl ether of choice and methacrylic acid to make component (a) and thus is present as a residual minor component of (a), the BPA-free vinyl ester. As noted below, in certain embodiments, the synthesis catalyst portion within (a) is generally present in an amount between 0.05 to less than 0.2 weight percent, based on the total weight of the composition. This amount is not otherwise critical as the synthesis catalyst is generally used in amounts effective in catalyzing the aforementioned reaction to form the BPA-free vinyl ester.

[0026] Thus, in some preferred embodiments, the amount of components (a) and (c) combined in composition is in the range of 40-90% by weight, whereby the amount of (meth)-acrylate diluent in the composition may be in the range of 10-60% by weight, all based on the weight of components (a) - (c). In other preferred embodiments, the amount of components (a) and (c)combined in composition is in the range of 80-90% by weight, and the amount of (meth)-acrylate diluent in the composition is in the range of 10-20% by weight, all based on the weight of components (a) - (c).

[0027] The BPA-free vinyl ester resins used according to the present invention can be defined as follows. Vinyl ester resins are ones resulting from the condensation reaction between an epoxy resins and (meth)-acrylic acid to yield materials having reactive unsaturated units only at the termini. For example, BPA-free vinyl ester resins of the present invention can be those introduced by reaction of BPA-free epoxy resins with (meth)-acrylic acid. Exemplary resins include diglycidyl ether of bisphenol-F, diglycidyl ether of bisphenol- S, epoxies of phenol- novolac type, epoxies of resorcinol diglycidyl ether, diglycidyl ether of butane diol and isomers, neopentyl glycol diglycidyl ether, epoxidized soybean oil or diglycidyl ether of cyclohexanediniethanol, among others. (Meth)-acrylamide may be used instead of (meth)-acrylic acid within the scope of the present invention. For the avoidance of doubt, the BPA-free resins described herein do not include resins which are derived from bisphenol-A.

[0028] The terms (meth)-acrylate monomer and (meth)-acrylate diluent, having 3 or more reactive alkenes, in certain embodiments refers to (meth)-acrylates monomers such as ethoxylated trimethylolpropane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, propoxylated glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tri(2-hydroxethyl)isocyanurate tri(meth)acrylate, ditrimethyolpropane tefra(meth)acrylate, dipentaerythritol penta(meth)acrylate, pentaerythritol tetra(meth)acrylate and dipentaerythritol hexa(meth)acrylate.

[0029] In other embodiments, the composition further comprises at least one difunctional reactive diluent. Examples of difunctional reactive diluents include 1,4-butanedioldi(meth)acrylate, 2,3-butanediol di(meth)acrylate, 1 ,6-hexanediol di(meth)acrylate and its isomers, triethyleneglycol di(meth)acrylate, diethyleneglycol di(meth)acrylate, ethyleneglycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, glycerol di(meth)acrylate, trimethylolpropane di(meth)acrylate, glycerol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polypropylene glycol 200-1,000 di(meth)acrylate, polyethylene glycol 200- 1,000 di(meth)acrylate, tricyclodecane dimethyol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, and / or tetraethylene glycol di(meth)acrylate. Preferred difunctional reactive diluents are triethyleneglycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 2,3-butanediol di(meth)acrylate, 1 ,6- hexanediol di(meth)acrylate, polyethylene glycol 200-400 di(meth)acrylate and / or neopentyl glycol di(meth)acrylate.

[0030] In another embodiment, the BPA-free vinyl ester contains an acid modification. Such modification is accomplished by the addition of a diacid and / or cyclic anhydride during the vinyl ester formation. Typical diacids and / or cyclic anhydrides include maleic anhydride, itaconic anhydride, phthalic anhydride, trimellitic anhydride, isophthalic acid, terephthalic acid, adipic acid, maleic acid, itaconic acid, fumaric acid, succinic anhydride, succinic acid, hexahydrophthalic anhydride and tetrahydrophthalic anhydride among others. The concentration of diacid and or / cyclic anhydride utilized in the composition according to the invention in one embodiment lies between 5-10 wt % and in another embodiment, this amount lies between 10-20 wt %.

[0031] Li a further embodiment, the composition comprises at least one initiator. Such initiators can be chosen from initiators which are suitable for thermal curing and / or photoinitiated curing. Thermal curing is understood to be using the means of heat to cure a resin composition. Thisprocess is well understood to also include the use of peroxides and accelerators of which transition metal salts are the most common type . In the case of a resin composition being used for pipe relining, the heat source could be heated water or pressurized gas passing through the relining. On the other hand, photoinitiated cure is understood to mean the curing of the resin composition using irradiation with light of a suitable wavelength. In the case of relining, the light source is generally supplied via lamps which are placed or moved through the center of the tubular objects. The quantity of initiator utilized in the composition according to the invention in one embodiment lies between 0.1 -5.0 wt % and in another embodiment, this amount lies between 0.1 -3.0 wt %.

[0032] In another embodiment of the invention, the initiator is a thermal initiator. Examples of suitable thermal initiators are organic peroxide derivatives and azo compounds like azobisisobutyronitrile (AIBN). The thermal initiator is preferably an organic peroxide, or a combination of two or more peroxides. Suitable peroxides include but are not restricted to peroxyesters (of the formula -C(O)OO-), peroxycarbonates (of the formula -OC(O)O-), diacylperoxides (of the formula -C(O)OOC(O)-), dialkylperoxides (of the formula -ROOR'-), etc. An extensive listing of examples of suitable peroxides can be found, for instance, in US 2002 / 0091214-Al, paragraph

[0018] ,

[0033] Examples of suitable organic peroxides include: peroxyester or peracids such as benzoyl peroxide and t-butylperesters; peracetates and perbenzoates; tertiary alkylhydroperoxides such t- butyl hydroperoxide; other peroxides such cumene hydroperoxide; a particular class of peroxides derived from a ketone and a hydroperoxide such methyl ethyl ketone peroxide and acetylacetone peroxide; diperoxyesters such as lauroyl peroxide; perethers such as peroxy diethyl ether. The most used organic peroxides are tertiary peresters or tertiary hydroperoxide. Mixtures of theseperoxides may be used in the context of the present invention. The peroxides may also be mixed peroxides, i.e. peroxides containing any two of different peroxy bearing moieties in one molecule. In other embodiments, the solid peroxides such as benzoyl peroxide or peroxy carbonate peroxide would be used.

[0034] Examples of suitable ketone peroxides are cyclohexanone peroxide, methyl-ethyl-ketone peroxide (MEK.P), acetylacetone peroxide, and methyl-isobutyl-ketone peroxide. Examples of suitable hydroperoxides are cumene hydroperoxide and tert butyl hydroperoxide.

[0035] In other embodiments of this invention, the initiator is a photoinitiator of Norish type I or Norish type II. For example, an a-hydroxy aryl ketone, or a cleavage type photoinitiator like Irgacure 184, Irgacure 369, Darocure 1173 (Ciba) or acyl phosphine oxide, for example Lucerin TPO, Lucerin TPO-L (BASF), Irgaucre 819 (Ciba) or mixtures thereof. In one embodiment, the photo initiator is an acyl phosphine oxide or a bis acyl phosphine oxide. In another embodiment, the bis acyl phosphine oxide is bis(2,4,6-trimethylbenzoyl) phenyl phosphine oxide (Irgacure 819). In certain embodiments, the quantity of photoinitiator is between 0.1 and 2.0 wt % or between 0.2 and 1.0 wt %.

[0036] The resin compositions according to the invention which contain a thermal initiator may further comprise an accelerator, which is in certain embodiments a transition metal compound and / or organic compound. Examples of suitable transition metal compounds are iron, manganese, copper, molybdenum, tungsten, vanadium, cobalt, nickel, chromium, or zinc compounds. The transition metal compounds are preferably a cobalt compound, a manganese compound, a zinc compound, or mixtures of these with other metal salts. Suitable cobalt compounds are for example cobalt octoate, cobalt neodecanoate or cobalt naphthenate. Suitable manganese compounds are for example manganese octoate, manganese neodecanoate ormanganese naphthenate. Suitable zinc compounds are zinc octoate, zinc neodecanoate or zinc naphthenate.

[0037] In a further embodiment, the compositions according to the invention further comprise one or more inhibitors. The inhibitor can be any radical inhibitor known to the one ski lied in the art of composites and can in certain embodiments be chosen from the group of phenolic compounds, stable radicals like N-oxyl based compounds and phenothiazines and / or galvinoxyl. Suitable examples of inhibitors that can be used in the compositions according to the invention are, for instance, methylbenzoquinone, 2 -methylhydroquinone, 2 -methoxyphenol, 4- methoxyphenol, 2,6-di-t-butylphenol, 2,4,6-trimethyl-phenol, 2,4,6-tris-dimethylaminomethyl phenol, 4,4'-thio-bis(3-methyl-6-t-butyrlphenol), 4,4'-isOpropylidene diphenol, 2,4-di-t- butylphenol, 2,6-di-t-butyl-4-methylphenol, 6,6-di-t-butyl-2,2-methylene di-p-cresol, hydroquinone, 2-t-butylhydroquinone, 2,5-di-t-butylhydroquinone, 2,6-di-t-butylhydroquinone, 2,6-dimethylhydroquinone, 2,3,5-trimethylhydroquinone, catechol, 4-t-butylcatechol, 4,6-di-t- butylcatechol, benzoquinone, 2,3,5,6-tetrachloro-l ,4-benzoquinone, 2,6-dimethylbenzoquinone, napthoquinone, l-oxyl-2,2,6,6-tetramethylpiperidine, l-oxyl-2,2,6,6-tetramethylpiperidine-4-ol (a compound also referred to as TEMPOL), l-oxyl-2,2,6,6-tetramethylpiperidine-4-one (a compound also referred to as TEMPON), l-oxyl-2,2,6,6-tetramethyl-4-carboxyl-piperidine (a compound also referred to as 4-carboxy-TEMPO), l-oxyl-2,2,5,5-tetramethylpyrrolidine, 1-oxyl- 2,2,5,5-tetramethyl-3-carboxylpyrrolidine (also called 3-carboxy-PROXYL), aluminium-N- nitrosophenylhydroxylamine, diethylhydroxylamine, phenothiazine and / or derivatives or combinations of any of these compounds.

[0038] In certain embodiments, the amount of inhibitor in the resin composition of this invention is in the range of 0,00001 to 5.0% by weight, from 0.0001 to 2.0% by weight, or from 0.001 to 1.0% by weight.

[0039] As used herein, the term "synthesis catalyst" will be used to define a compound used to increase the rate of reaction yielding a vinyl ester and does so without undergoing any chemical change during this process. In addition, this synthesis catalyst must possess an orthogonal functional group capabl e of further reacting during the curing of vinyl ester composition. Example classes of compounds include stannous compounds, phosphonium salts, amines, and ammonium salts. In one embodiment the synthesis catalyst will be an ammonium salt like diallyldimethylammonium chloride and / or 2-(dimethylamino) ethyl acrylate methyl chloride. In one embodiment, the synthesis catalyst will be an amine like N.N-dimethylaminoethyl acrylate and / or 2-(t-butylamino)ethyl methacrylate. In general terms, the synthesis catalyst component (c) is present in an amount of less than 0.25 weight %, or in a range of about 0.025-0.25 wt %, based on the total weight of the composition components, although this amount is not generally critical and is merely chosen as to be the effective amount required to catalyze the vinyl ester formation reaction, component (a).

[0040] The resin composition according to the invention contains, optionally, a filler in weight ratio of 0.05: 1 to 20: 1 or in a weight ratio of 0.2: 1 to 3: 1 , relative to the total weight percentages of the components. Suitable fillers include silica, microcrystalline silica, alumina trihydrate, calcium carbonate, mica, quartz powder, barite, fibers and / or talc.

[0041] As used herein, the term "styrene-free" will be understood to mean that the resin compositions of this invention contain neither styrene nor an analog of styrene. The term"(meth)-acrylate" will be understood to include both "acrylate" and "methacrylate" and the term "molecular weight" will be understood to mean weight average molecular weight.

[0042] Furthermore, the use of trifunctional (meth)-acrylates enhances the cure of the composite and allows a much lower percentage of unreacted materials to leach out of it. Both, difunctional and trifunctional (meth)-acrylates have the capacity under "free radical" curing conditions. Since trifimctional (meth)-acrylates have 50% more reactive sites than difunctional variants, the opportunities for a fully reacted pipe with the vinyl ester compositions herein described to leach any free materials are greatly reduced. Furthermore, the use of multifunctional (meth)-acrylates provides improved mechanical performance than those provided by styrene and similar monomers.

[0043] This invention can be further illustrated by the following Examples of certain embodiments thereof, although it will be understood that these Examples are included merely for purposes of illustration and are not intended to limit the scope of the invention unless otherwise specifically indicated.

[0044] Examples

[0045] Example 1. Bisphenol-A free vinyl ester resin was produced by the following procedure. Resorcinol diglycidyl ether (RGDE) and methacrylic acid were combined at 58.7 wt % and 41.1 w't %, respectively, in a resin kettle with diallyldimethylammonium chloride and butylated hydroxytoluene at 1,500 ppm and 1,300 ppm, respectively. The mixture was heated to 118 °C under air and held at a constant temperature, with agitation, until an acid number of X mg KOH / g and a viscosity of 40 P @ 60 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 80 wt% is achieved. This resin, which contains 10 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 1.

[0046] Example 2. Novolac vinyl ester resin is produced by the following procedure. Phenol Novolac epoxy and methacrylic acid are combined at 66.6 wt % and 33.0 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride, butylated hydroxytoluene, p-benzoquinone at 2,000 ppm, 2,000 ppm and 200 ppm, respectively. The mixture is heated to 117 °C under air and held at a constant temperature, with agitation, until an acid number of 23 mg KOH / g and viscosity of 45 at 80 °C are achieved. The resin is then added to ethoxylated trimethylolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 60 wt % is achieved. This resin, which contains 20 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 2-3.

[0047] Example 3. Bisphenol-A free vinyl ester resin was produced by the following procedure. Diglycidyl ether of cyclohexane dimethanol (CHDM-DGE) and methacrylic acid were combined at 65.1 wt % and 34.6 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride, butylated hydroxytoluene and 4-hydroxy TEMPO at 1,500 ppm, 2,000 ppm and 10 ppm, respectively. The mixture was heated to 120 °C under air and held at a constant temperature, with agitation, until an acid number of 35 mg KOH / g was achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 80 wt % is achieved. This resin, which contains 10 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 4.

[0048] Example 4. Bisphenol-A free vinyl ester resin was produced by the following procedure. 1,4-butanediol diglycidyl ether (BDODGE) and methacrylic acid were combined at 58.5 wl % and 41.2 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride, butylatedhydroxytoluene and 4-hydroxy TEMPO at 1,500 ppm, 2,000 ppm and 10 ppm, respectively. The mixture was heated to 113 °C under air and held at a constant temperature, with agitation, until an acid number of 35 nig KOH / g and a viscosity of 2 P @ 50 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 80 wt % is achieved. This resin, which contains 10 wt % trifonctional acrylate diluent, is the base for the formulations found in Table 5.

[0049] Example 5. Bisphenol-A free vinyl ester resin was produced by the following procedure. Neopentyl glycol digiycidyl ether (NPGDGE) and methacrylic acid were combined at 61.1 wt % and 38.6 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride, butylated hydroxytoluene and 4-hydroxy TEMPO at 1,500 ppm, 2,000 ppm and 10 ppm, respectively. The mixture was heated to 115 °C under air and held at a constant temperature, with agitation, until an acid number of 35 mg KOH / g and a viscosity of 2 P @ 50 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 80 wt % is achieved. This resin, which contains 10 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 6.

[0050] Example 6. Bisphenol-A free vinyl ester resin was produced by the following procedure. Epoxidized soybean oil (ESO) and methacrylic acid were combined at 77.0 wt % and 22.7 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride, butylated hydroxytoluene and 4-hydroxy TEMPO at 1 ,500 ppm, 2,000 ppm and 10 ppm, respectively. The mixture was heated to 120CC under air and held at a constant temperature, with agitation, until an acid number of 40 mg KOH / g and a viscosity of 23 P @. 50 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until asolids content of 80 wt % is achieved. This resin, which contains 10 wt % trifimctional acrylate diluent, is the base for the formulations found in Table 7.

[0051] Example 7. Bisphenol-A free vinyl ester resin was produced by the following procedure. Bisphenol-F (BPF) and methacrylic acid were combined at 66.4 wt % and 33.3 wt %, respectively, in a resin kettle with diallyldimethylanmionium chloride and butylated hydroxytoluene at 1,300 ppm and 1,000 ppm, respectively. Tire mixture was heated to 121CC under air and held at a constant temperature, with agitation, until an acid number of 12 mg KOH / 'g and a viscosity of 20 P @ 60 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 70 wt % is achieved. This resin, which contains 15 wt % trifimctional acrylate diluent, is the base for the formulations found in Table 8.

[0052] Example 8. Acid modified Novolac vinyl ester resin is produced by the following procedure. Phenol Novolac epoxy, methacrylic acid and maleic anhydride are combined at 63.4 wt %, 31.4 wt % and 5.2 wt % respectively, in a resin kettle with diallyldimethylammonium chloride, butylated hydroxytoluene and 4-hydroxy-TEMPO at 2,000 ppm, 2,000 ppm and 25 ppm, respectively. The mixture is heated to 117 °C under air and held at a constant temperature, with agitation, until an acid number of 44 mg KOH / g and viscosity of 74 P at 85 °C are achieved. The resin is then added to ethoxylated trimethylolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 60 wt % is achieved. This resin, which contains 20 wt % trifimctional acrylate diluent, is the base for the formulations found in Table 10.

[0053] Example 9. Acid modified Novolac vinyl ester resin is produced by the following procedure. Phenol Novolac epoxy, methacrylic acid and maleic anhydride are combined at 60.3 wt %, 29.9 -wt % and 9.8 wt % respectively, in a resin kettle with diallyldimethylammoniumchloride, butylated hydroxytoluene and 4-hydroxy-TEMPO at 2,000 ppm, 2,000 ppm and 25 ppm, respectively. The mixture is heated to 117 °C under air and held at a constant temperature, with agitation, until an acid number of 65 mg KOH / g and viscosity of 56 P at 100 °C are achieved. The resin is then added to ethoxylated trimethylolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 60 wt % is achieved. This resin, which contains 20 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 11.

[0054] Example 10. Acid modified Bisphenol-A free vinyl ester resin was produced by the following procedure. Bisphenol-F (BPF), methacrylic acid and maleic anhydride were combined at 63.0 wt %, 31.7 wt % and 5.7 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride and butylated hydroxytoluene at 1,300 ppm and 1,000 ppm, respectively. The mixture was heated to 121 °C under air and held at a constant temperature, with agitation, until an acid number of 35 mg KOH / g and a viscosity of 32 P @ 65 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethylene glycol dimethacrylate until a solids content of 70 wt % is achieved. This resin, which contains 15 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 12.

[0055] Example 11. Acid modified Bisphenol-A free vinyl ester resin was produced by the following procedure. Bisphenol-F (BPF), methacrylic acid and maleic anhydride were combined at 59.9 wt %, 30.1 wt % and 10.0 wt %, respectively, in a resin kettle with diallyldimethylammonium chloride and butylated hydroxytoluene at 1,300 ppm and 1,000 ppm, respectively. The mixture was heated to 121 °C under air and held at a constant temperature, with agitation, until an acid number of 60 mg KOH / g and a viscosity of 35 P @ 70 °C were achieved. The resin was then added to ethoxylated trimethyolpropane triacrylate and triethyleneglycol dimethacrylate until a solids content of 70 wt % is achieved. This resin, which contains 15 wt % trifunctional acrylate diluent, is the base for the formulations found in Table 13.

[0056] Example Formulations

[0057] Table tIngredient %Example 1 RDGE vinyl ester resin 72.60(contains 10% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Ethoxylated trimethyolpropane triacrylate 13.00Triethylene glycol dimethacrylate 13.00Total 100.00

[0058] Table 2Ingredient %Example 2 Novolac vinyl ester resin 64.35(contains 20% ethoxylated trimethyol triacryiate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.25Polyoxyethylenesorbitan monolaurate 0.20Ethoxylated trimethyolpropane triacrylate 17.00Triethylene glycol dimethacrylate 17.00Total 100.00

[0059] Table 3Ingredient %Example 2 Novolac vinyl ester resin 85.56(contains 20% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Ethoxylated trimethyolpropane triacrylate 3.00Polyethylene glycol 400 diacrylate 10.0012% Cobalt octoate 0.0216% Zinc Hex-Cem 0.02Total 100.00

[0060] Table 4Ingredient %Example 3 CHDM-DGE vinyl ester resin 98.60(contains 10% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Total 100.00

[0061] Table 5Ingredient %Example 4 BDODGE vinyl ester resin 98.60(contains 10% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Total 100.00

[0062] Table 6Ingredient %Example 5 NPGDGE vinyl ester resin 98.60(contains 10% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Total 100.00

[0063] Table ?Ingredient %Example 6 ESO vinyl ester resin (contains 60.6010% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Ethoxylated trimethyolpropane triacrylate 19.00Triethylene glycol dimethacryiate 19.00Total 100.00

[0064] Table 8Ingredient %Example 7 ESO vinyl ester resin (contains 60.6010% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Ethoxylated trimethyolpropane triacrylate 19.00Triethylene glycol dimethacrylate 19.00Total 100.00

[0065] Table 9Ingredient %Example 7 BPF vinyl ester resin (contains 78.6015% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.20Aerosil 200HV 1.00Polyoxyethylenesorbitan monolaurate 0.20Ethoxylated trimethyolpropane triacrylate 10.00Triethylene glycol dimethacrylate 10.00Total 100.00

[0066] Table 10Ingredient %Example 8 Acid Modified Novolac vinyl 86.95 ester resin (contains 20% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.05Ethoxylated trimethyolpropane triacrylate 5.00Triethylene glycol dimethacrylate 8.00Total 100.00

[0067] Table 11Ingredient %Example 9 Acid Modified Novolac vinyl 79.95 ester resin (contains 20% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.05Ethoxylated trimethyolpropane triacrylate 4.00Triethylene glycol dimethacrylate 16.00Total 100.00

[0068] Table 12Ingredient %Example 10 Acid Modified BPF vinyl ester 79.95 resin (contains 20% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.05Ethoxylated trimethyolpropane triacrylate 10.00Triethylene glycol dimethacrylate 10.00Total 100.00

[0069] Table 13Ingredient %Example 11 Acid Modified BPF vinyl ester 79.95 resin (contains 20% ethoxylated trimethyol triacrylate)Butadiene copolymer air release agent 0.05Ethoxylated trimethyolpropane triacrylate 10.00Triethylene glycol dimethacrylate 10.00Total 100.00Statement of Industrial ApplicabilityTire present invention is an improvement on technology used for relining pipes, including pipes carrying potable water, which are ubiquitous in the modern world. The improvement includes the elimination of BPA from these systems, which is a potentially harmfol chemical if it leaches into a drinking water supply. Moreover, the present invention is still capable of curing under both thermal and photoinitiation strategies, impregnating felt and glass fibers, or a combination of fabric and glass fiber, which are widely-used reinforcements within the CIPP industry.

Claims

CLAIMS:We claim:

1. A curable resin composition, comprising:(a) a BPA-free vinyl ester;(b) a (meth)-acrylate diluent having two or more reactive moieties; and(c) a synthesis catalyst which contains at least one reactive double bond.

2. The composition of claim 1 , further comprising at least one di-functional reactive diluent.

3. The composition of claim 2, wherein the di-functional reactive diluent is selected from the group comprising 1 ,4-butanediol di(meth)acrylate, 2, 3 -butanediol di(meth)acrylate, 1,6- hexanedlol di(meth)acrylate and its isomers, triethyleneglycol di(meth)acrylate, diethyleneglycol di(meth)acrylate, ethyleneglycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, glycerol di(meth)acrylate, trimethylolpropane di(meth)acrylate, glycerol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polypropylene glycol 200-1,000 di(meth)acrylate, polyethylene glycol 200-1,000 di(meth)acrylate, tricyclodecane dimethyol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, and / or tetraethylene glycol di(meth)acrylate.

4. The composition of claim 2, wherein the di-functional reactive diluent is selected from the group comprising triethyleneglycol di(meth)acrylate, 1 ,4-butanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, 1 ,4-butanediol di(meth)acrylate, 2,3 -butanediol di(meth)acrylate, 1,6-hexanediol di(meth)aciylate, polyethylene glycol 200-400 di(meth)acrylate and / or neopentyl glycol di(meth)acrylate.

5. The composition of claim 1, wherein component (b) is selected from the group comprising ethoxylated trimethylolpropane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, propoxylated glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tri(2-hydroxethyl)isocyanurate tri(meth)acrylate, ditrimethyolpropane tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, pentaerythritol tetra(meth)acrylate and dipentaerythritol hexa(meth)acrylate.

6. The composition of claim 1, wherein component (c) possesses an orthogonal functional group capable of further reacting during the curing of the composition.

7. The composition of claim 6, wherein component (c) is selected from the group comprising ammonium salts or amines.

8. The composition of claim 7, wherein component (c) is selected from the group comprising diallyldimethylammonium chloride, 2 -(dimethylamino) ethyl acrylate methyl chloride, N,N-dimethylaminoethyl acrylate and / or 2-(t-butylamino)ethyl methacrylate.

9. The composition of claim 1 , further comprising at least one initiator.

10. The composition of claim 1 , further comprising at least one inhibitor.

11. The composition of claim 1, wherein component (a) is produced by the reaction of a BPA-free epoxy resin with either (metli)-acrylic acid or (Meth)-acrylamide in the presence of component (c).

12. The composition of claim 11 , wherein said BPA-free epoxy resin is selected from the group comprising diglycidyl ether of bisphenol-F, diglycidyl ether ofbisphenol-S, epoxies of phenol-novolac type, epoxies of resorcinol diglycidyl ether, diglycidyl ether of butane diol and isomers, neopentyl glycol diglycidyl ether, epoxidized soybean oil or diglycidyl ether of cyclo hexanedimethano I .

13. The composition of claim 11 , wherein said BPA-free epoxy resin is selected from the group comprising diglycidyl ether of bisphenol-F, diglycidyl ether ofbisphenol-S, epoxies of resorcinol diglycidyl ether, diglycidyl ether of butane diol and isomers, neopentyl glycol diglycidyl ether, epoxidized soybean oil or diglycidyl ether of cyclohexanedimethanol.

14. The composition of claim 1 , wherein the composition includes component (b) in an amount of about 10-60% by weight, based on the total weight of the composition, and wherein components (a) and (c) combined are present in an amount of about 40-90% by weight, based on the total weight of the composition.

15. The composition of claim 14, wherein component (b) is present in an amount of about 10-20% by weight, based on the total weight of the composition, and wherein components (a)and (c) combined are present in an amount of about 80-90% by weight, based on the total weight of the composition16. The composition of claim 1, wherein the BPA-free vinyl ester contains an acid modification.

17. The composition of claim 16, wherein said acid modification is accomplished with the addition of a diacid and / or cyclic anhydride during formation of said BPA-free vinyl ester.

18. The composition of claim 17, wherein said diacid and / or cyclic anhydride is a compound selected from the group comprising: maleic anhydride, itaconic anhydride, phthalic anhydride, trimellitic anhydride, isophthalic acid, terephthalic acid, adipic acid, maleic acid, itaconic acid, succinic anhydride, succinic acid, hexahydrophthalic anhydride tetrahydrophthalic anhydride, and fumaric acid.

19. The composition of claim 16, wherein said diacid and / or cyclic anhydride is present in the composition in a concentration of 10-20 wt %.

20. The composition of claim 19, wherein said diacid and / or cyclic anhydride is present in the composition in a concentration of 5-10 wt %.

21. The composition of claim 1, wherein said resin composition does not include styrene.

22. A flexible, sleeve-shaped supporting or reinforcing material which is impregnated with the curable resin of claim 1.

23. A method for preparing a cured composite article, said method comprising the steps of:(a) providing a resin having the composition of claim 1 ;(b) impregnating a substrate with said resin; and(c) subjecting said substrate to a thermal or photo-initiated curing process.

24. The method of claim 23, wherein said substrate is selected from a group comprising fiberglass or carbon fiber.

25. A method for (re)lining a tube, tank, or vessel with a curable resin composite structure, said method comprising the steps of:(a) introducing into said tube, tank or vessel, a flexible sleeve containing the composition of claim 1 ;(b) pressurizing said tube, tank or vessel, whereby said flexible sleeve is forced against the wall of said tube, tank or vessel; and(c) subjecting said flexible sleeve to a thermal or photo-initiated curing process.