Accelerated peroxide curing resin composition with long open time

Abstract

Curable resin compositions with a long open time at room temperature and a short curing time at high temperatures are produced using a curable resin that can be cured with one or more liquid organic peroxides or mixtures thereof, and an accelerator / activator accelerator containing a metal salt and a thiol-functionalized organic compound.

Description

Technical Field

[0001] The present invention relates to a resin composition that can be cured using liquid organic peroxides, organic peroxide blends, and mixtures thereof, has a long pot life (open time) at ambient temperature (room temperature), and can be cured rapidly at elevated temperatures, and is particularly suitable for composite applications such as pultrusion, in-place cure pipes, and resin transfer molding.

Background Art

[0002] Composite materials that combine a curable thermosetting resin such as an unsaturated polyester resin or a vinyl ester resin with an optional reinforcing filler such as glass fiber or carbon fiber typically exhibit advantageous mechanical properties such as high strength and high stiffness. Curing of the resin in such systems is often achieved by initiation of a free radical reaction using an organic peroxide, leading to crosslinking of the curable resin. In at least some end uses of such composite systems, it is desirable for the resin to cure rapidly when heated to elevated temperatures in order to reduce manufacturing costs and increase the efficiency of composite material manufacturing operations. When a curable resin containing a peroxide is heated, the peroxide decomposes to generate free radical species, initiating the curing of the resin, and the liquid resin cures to improve the desirable physical properties of the composite system. The composite material is considered to be cured when the physical shape of the composite part is permanently fixed or permanently cured into a rigid thermosetting composite part at the expected service temperature of the composite part. However, at the same time, it is desirable for the mixture or blend of curable resin / peroxide / reinforcing filler to have a relatively slow curing rate at ambient temperature (room temperature) in order to ensure sufficient time to mold the composite part into the target shape. In the present disclosure, curable thermosetting resins such as unsaturated polyester resins and optional reinforcing fillers are cured by the organic peroxides, organic peroxide blends, and mixtures thereof described herein.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Generally speaking, high-temperature curing using organic peroxides relies on initiating the polymerization of curable resins, such as unsaturated polyester resins, by the thermal decomposition of such organic peroxides. To achieve a curing time sufficient to ensure a reasonable cycle time, peroxides with a relatively short half-life at room temperature are used as primary initiators. Such peroxides are typically selected from certain peroxyesters or peroxydicarbonates that must be stored below room temperature (freezing temperature) due to their instability, such as tert-butylperoxyneodecanoate, or from solid peroxydicarbonates such as di(2-ethylhexyl)peroxydicarbonate or di(4-tert-butylcyclohexyl)peroxydicarbonate.

[0004] While these types of peroxides are effective, they are not ideal because they require storage in a freezer (in the case of liquid peroxides), potentially increasing storage costs and safety risks, and (in the case of solid peroxides) require additional effort and cost to disperse into curing resins, and are subject to storage regulations under fire safety laws.

[0005] Conventional composite material applications typically use one of two initiation packages: a mixture of solid (or paste) peroxydicarbonates as the primary initiator, or a mixture based on freezer storage. An example of a solid peroxydicarbonate is di(4-tert-butylcyclohexyl)peroxydicarbonate (known by the trademarks Perkadox® 16 or Norox® 600-CL2). The recommended storage temperature for this solid peroxydicarbonate peroxide is 20°C, but this applies only to the solid form. The liquid solution form of this peroxide requires freezer storage. Examples of liquid freezer-storage peroxides include LUPEROX® 223 and LUPEROX® 10. Both systems have drawbacks. Solid organic peroxide systems require thorough mixing with the resin to ensure proper dispersion and dissolution. Therefore, they are often diluted with styrene or another solvent before being introduced into the resin, which increases cost, inefficiency, processing steps, and can lead to harmful environmental exposure.

[0006] Furthermore, since transition metal salts are generally considered destabilizing agents in the presence of these organic peroxides, it is known to those skilled in the art that organic peroxide classes such as peroxyesters, hemiperoxyketals, peroxyketals, monoperoxycarbonates, ketone peroxides, diacyls, and hydroperoxides should not come into direct contact with transition metal salts. These transition metal salts or metal soaps are often referred to in the art as accelerators, activators, or propellants. In addition, it is recommended that these peroxides not come into contact with the transition metals themselves, such as iron or copper. For example, many safety data sheets for organic peroxides warn that transition metal salts, metal soaps, and / or metal activators have poor storage compatibility with organic peroxides.

[0007] U.S. Patent Publication No. 4,380,605 discloses that crosslinking of unsaturated polyester resins at room temperature is promoted by mercapto compounds and metal salts in the presence of a peroxyester initiator, wherein the metal is selected from the group consisting of copper, iron, or a mixture of metal salts.

[0008] U.S. Patent Publication No. 5,310,826 discloses accelerator compositions for the free radical polymerization of unsaturated polyesters and the curing of unsaturated polyesters and polyurethanes.

[0009] U.S. Patent Publication No. 5,235,010 discloses an accelerator composition for curing various unsaturated resins, comprising a complex of a specific metal salt and an oxygen-containing compound, and possibly including thiol compounds. Peroxide initiators may be used in combination with such complexes.

[0010] U.S. Patent Application Publication No. 2010 / 0120977 discloses an accelerator solution comprising a complexing agent selected from the group consisting of a complexing agent having a nitrogen atom and a hydroxyl group and bipyridine, a salt of a metal selected from the group consisting of transition metals, magnesium and lithium, and an optional solvent.

[0011] U.S. Patent Application Publication 2011 / 0250373 discloses the use of nitroxides to control free radical curing resin systems in the manufacture of thermosetting materials, in which radical initiators and free radical polymerization initiators selected from diacyl peroxides, peracid esters, peroxydicarbonates, and mixtures thereof may be used.

[0012] International Publication 2008 / 003496 describes a two-component composition comprising a first component and a second component, wherein the first component is a resin composition comprising an unsaturated polyester resin or vinyl ester resin, a manganese compound and a thiol-containing compound, and the second component comprises hydrogen peroxide or an alkyl hydroperoxide.

[0013] U.S. Patent Publication No. 11,873,381 discloses a curable resin composition comprising a curable resin, a room-temperature stable organic peroxide other than perketal that is liquid at 25°C, a room-temperature stable perketal that is liquid at 25°C, a metal salt, a thiol-functionalized organic compound, and a free radical trap. The curable resin composition remains substantially liquid at 25°C. [Means for solving the problem]

[0014] A curable resin composition is provided, which is produced using a curable unsaturated polyester resin that can be cured with at least one liquid organic peroxide formulation, and comprises a first component comprising at least one non-room temperature stable liquid organic peroxide and at least one room temperature stable liquid organic peroxide, and a second component (also called an accelerator / activator / promoter) comprising at least one metal salt, at least one thiol-functionalized organic compound, and an optional solvent.

[0015] Non-room temperature liquid organic peroxide formulations are defined as those with a half-life of less than 100°C per hour; on the other hand, room temperature liquid organic peroxide formulations have a half-life of 100°C or higher per hour.

[0016] Preferred curable resins include (meth)acrylate resins, unsaturated polyester resins, and vinyl ester resins. The curable resin may also contain reinforcing fillers. The shelf life of the curable resin composition can be extended by refrigeration before the curing operation. The curable resin composition is useful for applications such as plutonization, in-place cured pipes (CIPP), and resin transfer molding (RTM). Furthermore, the first and second components may be mixed before being combined with the curable resin. Therefore, transition metal salts (such as ZnCl2) and thiol organic compounds dissolved in a suitable solvent can be safely mixed with various organic peroxides for several hours at room temperature without any visible reaction. This result is unexpected, as transition metal halides are known to promote the decomposition of organic peroxides.

[0017] Furthermore, the inventors have surprisingly discovered that it is possible to mix peroxide blend components with accelerator / activator / promoting components (metal salts and thiol-functionalized organic compounds) without using free radical traps including nitroxide type (e.g., TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl), 4-OH TEMPO, or SG-1 nitroxide) and quinone type (e.g., MTBHQ or mono-tert-butylhydroquinone, HQMME, or hydroquinone monomethyl ether).

[0018] Surprisingly, preferred organic peroxide formulations containing the accelerator components described herein are relatively stable. Stability means that the formulation (composition or blend) does not decompose immediately at temperatures up to 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 28, or 30°C, which is measured by raising the temperature of the composition for at least 1 hour, or at least 23 hours, or at least 5-8 hours, or at least 8-10 hours, or at least 10-15 hours, or up to 24 hours. Such organic peroxide activator compositions offer the additional advantage of allowing the peroxide and activator to be further and completely mixed with the unsaturated polyester resin. When a peroxide mixture containing a metal salt and a thiol-functionalized organic compound is added to a curable resin and heat is applied, the resin exothermically begins to cure. In other words, combining metal salts and thiol-functionalized organic compounds as an accelerator / activator / promoter system and adding them directly to organic peroxide formulations yields an unexpectedly temperature-stable and complete curing system, while still allowing for rapid and effective curing of unsaturated polyester resins at high temperatures. It is quite unexpected that a mixture of transition metal salts and thiol-functionalized compounds can be safely stored and then directly added to organic peroxides at room temperature without immediate decomposition of the organic peroxides.

[0019] A curable resin composition is provided. The curable resin composition includes: a) At least one curable resin that can be cured by a liquid organic peroxide; b) At least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; c) Optionally, at least one non-room temperature stable organic peroxide that is liquid at 10°C or below and has a half-life temperature of less than 100°C; d) At least one salt of at least one metal, including at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; e) at least one thiol-functionalized organic compound; and f) Optionally, at least one solvent comprising at least one of an alcohol, glycol, or glycol ether.

[0020] A method for preparing a cured composition is also provided. This method includes the following steps: a) At least one curable resin that can be cured by an organic peroxide; b) At least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; c) Optionally, at least one non-room temperature stable organic peroxide that is liquid at 10°C or below and has a half-life temperature of less than 100°C; d) At least one salt of at least one metal, including at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; e) at least one thiol-functionalized organic compound; and f) Optionally, at least one solvent comprising at least one alcohol, glycol, or glycol ether; To provide a curable resin composition by combining the following; and Heating the curable resin composition to a temperature effective for initiating the curing of the curable resin composition.

[0021] A curing system is also provided. This curing system comprises i) a first component and ii) a second component. The first component includes: At least one room temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher for 1 hour; and At least one non-room temperature stable organic peroxide that is liquid at 10°C or lower and has a half-life temperature of less than 100°C for 1 hour.

[0022] The second component of the curing system includes the following: At least one salt of at least one metal containing at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; At least one thiol-functionalized organic compound; and Optionally, at least one solvent containing at least one of an alcohol, a glycol, or a glycol ether.

[0023] According to one embodiment, the first component optionally substantially does not contain styrene.

[0024] There is provided a curing system in which the above i) the first component and ii) the second component are combined to form a single room temperature stable liquid curing system.

[0025] There is also provided a curable resin composition. The curable resin composition includes the following: a) At least one curable resin including at least one of an alkyd resin, an unsaturated polyester resin, a vinyl ester resin, or a (meth)acrylate resin, or a mixture or blend thereof, wherein the curable resin is curable by a liquid organic peroxide; b) At least one liquid organic peroxide selected from the following group: i) A room temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher for 1 hour; or ii) A non-room temperature stable organic peroxide that is liquid at 10°C or lower and has a half-life temperature of less than 100°C for 1 hour; or iii) A blend or mixture of organic peroxide (i) and organic peroxide (ii); c) At least one salt of at least one metal, including at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; d) at least one thiol-functionalized organic compound; and e) Optionally, at least one solvent comprising at least one of an alcohol, glycol, or glycol ether.

[0026] A liquid organic peroxide composition is also provided. This liquid organic peroxide composition comprises the following blend: The first organic peroxide; Second organic peroxide; At least one transition metal salt dissolved in a solvent containing at least one alcohol, glycol, or glycol ether; and At least one thiol-functionalized organic compound is provided. This blend is stable at 18°C ​​or above, preferably 20°C or above, more preferably 23°C or above, for at least 1 hour, preferably at least 2 to 8 hours, more preferably at least 8 to 15 hours, and most preferably at least 24 hours. [Brief explanation of the drawing]

[0027] [Figure 1] Figure 1 shows the results of peroxide curing of unsaturated polyester resin (UPR) using a novel accelerator solution of the present invention, according to exemplary embodiments of the present disclosure. [Figure 2] Figure 2 shows the results of peroxide curing of UPR using a novel accelerator solution of the present invention, according to another exemplary embodiment of the present disclosure. [Figure 3] Figure 3 shows the unexpected stability of the peroxide and the subsequent effective exothermic reaction of the peroxide when mixed with the novel accelerator solution of the present invention, according to an exemplary embodiment of the present invention. [Figure 4] Figure 4 shows a comparative example of the decrease in peroxide stability when ZnCl2, a transition metal known to destabilize (promote) organic peroxides, is mixed with peroxide (without resin). [Figure 5]Figure 5 shows an example of unexpected peroxide stability when only peroxide (without resin) is mixed with the novel accelerator solution of the exemplary embodiment of this disclosure. [Figure 6] Figure 6 shows the results of peroxide curing of UPR using the novel accelerator solution of the present invention, according to exemplary embodiments of the present disclosure. [Figure 7] Figure 7 shows the results of peroxide curing of UPR using a novel accelerator solution of the present invention, according to another exemplary embodiment of the present disclosure. [Modes for carrying out the invention]

[0028] Information regarding the one-hour half-lives of various organic peroxides is found in LUPEROX® Organic Peroxides Arkema Inc., General Catalog Americas, and Arkema (Colombes Cedex) High Polymers catalog, and is incorporated herein by reference in its entirety for all purposes.

[0029] Half-life is the time it takes for 50% of a peroxide to decompose at a specified temperature, and half-life temperature is the temperature at which 50% of a peroxide decomposes in a specified time, as described in “SAFETY AND HANDLING OF ORGANIC PEROXIDES: A Guide Prepared by the Organic Peroxide Producers Safety Division of Plastics Industry Association”, Plastics Industry Association, Inc., OPPSD Bulletin AS-109 (August 2018), which is incorporated herein by reference in its entirety for all purposes.

[0030] As used herein, the terms “liquid” and “liquid state” mean that the material is liquid (fluid or pourable) at the temperature specified, in the form of a solution, or in itself a (pure) liquid (fluid or pourable).

[0031] As used herein, the term “stable” means that, with respect to an organic peroxide formulation, composition, or blend, the formulation (composition or blend) does not immediately decompose in a temperature range of 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, or 28, and even up to 30°C, which can be measured by the temperature rise of the formulation, composition, or blend over at least 1 hour, or at least 2-3 hours, or at least 5-8 hours, or at least 8-10 hours, or at least 10-15 hours, or up to 24 hours. Such organic peroxide activator compositions offer the additional advantage of allowing the peroxide and activator to be more completely mixed into the peroxide curable resin. When a peroxide mixture containing a metal salt and a thiol-functionalized organic compound is added to a curable resin and heat is applied, the combination of the resin and peroxide formulation generates heat and begins to cure. In other words, combining metal salts and thiol-functionalized organic compounds as an accelerator / activator / promoter system and adding them directly to organic peroxide formulations yields an unexpectedly temperature-stable and complete curing system, while still allowing for rapid and effective curing of curable resins at high temperatures. The fact that mixtures of transition metal salts and thiol-functionalized compounds can be safely stored and then directly added to organic peroxides at room temperature without immediate decomposition is quite unexpected.

[0032] hardening resin The curable resin used here is initially a liquid, but when mixed with an organic peroxide compound and heated, it polymerizes or reacts to form a solid (thermosetting) article.

[0033] Suitable curable resins that may be used in embodiments of this disclosure include, but are not limited to, alkyd resins, unsaturated polyester (UP) resins, vinyl ester resins, (meth)acrylate resins (also called acrylic resins), and mixtures thereof. Preferred resins include (meth)acrylate resins, unsaturated polyester resins, and vinyl ester resins. In this application, the terms "unsaturated polyester resin" and "UP resin" refer to combinations of unsaturated polyester resins with ethylenically unsaturated monomer compounds such as styrene, which are typically used to reduce the viscosity of (uncured) unsaturated polyester resins, promote crosslinking, and exhibit useful physical properties in cured composite materials. The term "(meth)acrylate resin" refers to combinations of acrylate resins and / or methacrylate resins with ethylenically unsaturated monomer compounds. Such UP resins and acrylate resins are well known in the art and are commercially available.

[0034] Unsaturated polyester resins useful in embodiments of this disclosure include reactive resins dissolved in polymerizable monomers or mixtures of monomers. These reactive resins are formed by condensing saturated dicarboxylic acids or anhydrides with unsaturated dicarboxylic acids or anhydrides and dihydric alcohols. Examples of these polyester resins include reaction products of saturated dicarboxylic acids or anhydrides (e.g., phthalic anhydride, isophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, tetrachlorophthalic anhydride, hexachloroendomethylenetetrahydrophthalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, etc.) with unsaturated dicarboxylic acids or anhydrides (e.g., maleic anhydride, fumaric acid, chloromaleic acid, itaconic acid, citraconic acid, mesaconic acid, etc.) with dihydric alcohols (e.g., ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, neopentyl glycol, etc.). Small amounts of polyhydric alcohols (such as glycerol, pentaerythritol, trimethylopropane, and sorbital) can also be used in combination with glycols.

[0035] According to some embodiments, the curable resin may include at least one of an alkyd resin, an unsaturated polyester resin, a vinyl ester resin, or a (meth)acrylate resin, or a mixture or blend thereof. According to some embodiments, the curable resin may include at least one of an unsaturated polyester resin, a vinyl ester resin, or a combination thereof. In some embodiments, the curable resin may include an unsaturated polyester resin. In yet other embodiments, the curable resin may include a vinyl ester resin.

[0036] In the case of unsaturated polyester resins, the final three-dimensional (crosslinked) structure can be produced by reacting the unsaturated polyester with an unsaturated monomer that can react with the unsaturated polyester to form crosslinks, via the unsaturated acid component of the unsaturated polyester. Suitable unsaturated monomers include styrene, methylstyrene, dimethylstyrene, vinyltoluene, divinylbenzene, dichlorostyrene, methyl acrylate, methyl methacrylate, ethyl acrylate, diallyl phthalate, vinyl acetate, triallyl cyanurate, acrylonitrile, acrylamide, and mixtures thereof. The relative amounts of unsaturated polyester and unsaturated monomer in the unsaturated polyester resin composition can be varied over a wide range. Unsaturated polyester resin compositions typically contain 20% to 80% by weight of monomers, with the monomer content preferably in the range of 30% to 70% by weight.

[0037] Alkyd resins include resins that are polymerization products of polybasic acids modified with polyhydric alcohols and monobasic fatty acids, and usually contain at least some amount of unsaturated fatty acids. The polybasic acid may also be a dicarboxylic acid, most commonly phthalic anhydride, isophthalic acid, maleic anhydride, and itaconic acid. Mixtures of two or more acids (or their anhydrides) can also be used. The second acid component is a monocarboxylic acid, represented by drying oil acids such as linoleic acid, linolenic acid, and eleostearic acid, and other acids containing two or more double bonds that are either carbon-conjugated or non-conjugated to each other.

[0038] Vinyl ester resins include resins produced by esterifying epoxy resin with an unsaturated carboxylic acid such as acrylic acid or methacrylic acid, and then dissolving the resulting product in a reactive solvent such as styrene (typically at a concentration of 35-45 percent by weight).

[0039] (Meth)acrylate resins include acrylates; methacrylates; diacrylates; and dimethacrylates; acrylate and / or methacrylate-functionalized substances; highly functionalized acrylates and methacrylates containing both monomers and oligomers; and combinations thereof.

[0040] Non-limiting examples of suitable ethylenically unsaturated monomer compounds include styrene and styrene derivatives, e.g., α-methylstyrene; vinyltoluene; indene; divinylbenzene; vinylpyrrolidone; vinylsiloxane; vinylcaprolactam; stilbene; also diallyl phthalate; dibenzylideneacetone; allylbenzene; methyl methacrylate; methyl acrylate; acrylic acid; methacrylic acid; diacrylate; dimethacrylate; acrylamide; vinyl acetate; triallyl cyanurate; triallyl isocyanurate; allyl compounds (such as (di)ethylene glycol diallyl carbonate); chlorostyrene; tert-butylstyrene; tert-butyl acrylate; butanediol dimethacrylate; and mixtures thereof. Suitable examples of (meth)acrylate reactive diluents include PEG200 di(meth)acrylate; 1,4-butanediol di(meth)acrylate; 1,3-butanediol di(meth)acrylate; 2,3-butanediol di(meth)acrylate; 1,6-hexanediol di(meth)acrylate and its isomers; diethylene glycol di(meth)acrylate; triethylene glycol di(meth)acrylate; glycerol di(meth)acrylate; trimethylolpropane di(meth)acrylate; neopentyl glycol di Examples include (meth)acrylate; dipropylene glycol di(meth)acrylate; tripropylene glycol di(meth)acrylate; PPG250 di(meth)acrylate; tricyclodecane dimethylol di(meth)acrylate; 1,10-decanediol di(meth)acrylate; tetraethylene glycol di(meth)acrylate; trimethylolpropane tri(meth)acrylate; glycidyl(meth)acrylate; (bis)maleimide; (bis)citraconimide; (bis)itaconimide; and mixtures thereof.

[0041] The amount of ethylenically unsaturated monomer in the curable resin used according to embodiments of this disclosure is preferably at least 0.1% by weight, more preferably at least 1% by weight, and most preferably at least 5% by weight, based on the weight of the curable resin component. The amount of ethylenically unsaturated monomer is preferably 50% by weight or less, more preferably 40% by weight or less, and most preferably 35% by weight or less.

[0042] Examples of commercially available unsaturated polyester resins suitable for the applications discussed in this disclosure include Pultru® resin from AOC; VIPEL resin from AOC; COR31 and COR30 resins from Interplastic; Aropol® resin from Ashland; and DION and STYPOL resins from Polynt / Reichold.

[0043] Examples of commercially available vinyl ester resins suitable for the applications discussed in this disclosure include Pultru® resin from AOC; VIPEL® resin from AOC; CORVE resin from Interplastic; and Derakane® resin from Ashland.

[0044] Examples of commercially available (meth)acrylate resins suitable for the applications discussed in this disclosure include MODAR® from Ashland and Elium® from Arkema.

[0045] organic peroxide In one embodiment of the present invention, the curable resin comprises at least one room-temperature stable organic peroxide that is liquid at 25°C. These room-temperature stable liquid peroxides have a half-life temperature of 100°C or higher and can cure the curable resin composition described herein.

[0046] In one embodiment of the present invention, the curable resin comprises at least one non-room temperature stable organic peroxide that is liquid at 10°C and has a half-life temperature of less than 100°C over one hour.

[0047] In another embodiment, the curable resin composition is characterized by comprising at least two different types of organic peroxides that together can cure the curable resin composition as described herein. Both types of organic peroxides are advantageous to be in liquid form, or the blend may be in liquid form. One type of organic peroxide can be stored stably at room temperature or above. Hereinafter, these will be referred to as “room temperature stable” organic peroxides. If the loss of peroxide concentration is 2% by weight or less, they can be safely stored for 6 months at 20°C or above, or 25°C or above, or 30°C or below. Room temperature stable organic peroxides generally have a 1-hour half-life temperature of 100°C or above. This type of room temperature stable organic peroxide may have a 10-hour half-life temperature of 80°C or above. In the context of this disclosure, “room temperature stable” means an organic peroxide whose maximum storage temperature is 30°C or above, which is recommended to maintain a peroxide concentration loss of 2% or less for 6 months to 1 year. However, according to certain aspects of this disclosure, room temperature stable organic peroxides present in a curable resin composition may have a 10-hour half-life temperature of 80°C or above. In yet another embodiment, room-temperature stable organic peroxides exhibit a loss of peroxide concentration of 2% or less even after storage for 3 months, 6 months, 9 months, or up to 12 months at a maximum storage temperature limit of 30°C or 38°C (100°F). Appropriate storage temperature limits for maintaining the analysis of organic peroxides are specified in the product safety data sheet (SDS) or the commercial product catalog.

[0048] Examples of room-temperature stable organic peroxides useful in embodiments of this disclosure include peroxyesters, hemiperoxyketals, peroxyketals, monoperoxycarbonates, diacyls, ketone peroxides, and hydroperoxides. Preferred room-temperature stable organic peroxides are peroxyesters, hemiperoxyketals, peroxyketals, and monoperoxycarbonates. Most preferred are peroxyester, hemiperoxyketal, peroxyketal, and monoperoxycarbonate type organic peroxides. More preferred are peroxyester peroxides, peroxyketals, and monoperoxycarbonate peroxides. Even more preferred room-temperature stable organic peroxides are peroxyester and monoperoxycarbonate type peroxides. Preferred and more preferred room-temperature stable organic peroxides may have tert-butylperoxy, tert-amylperoxy, tert-hexylperoxy, or tert-octylperoxy functional groups.

[0049] Non-limiting examples of suitable room-temperature stable organic peroxides are as follows: 1-tert-amylperoxy-1-methoxycyclohexane (LUPEROX® V10); 1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane (LUPEROX® 231); 1,1-di(t-amylperoxy)cyclohexane (LUPEROX® 531M80); 1,1-di(1-butylperoxy)cyclohexane (LUPEROX® 331M80); 2,2-di(t-butylperoxy) Xy)butane (LUPEROX® 520M50); n-butyl 4,4-di(t-butylperoxy)valerate (LUPEROX® 230); ethyl 3,3-di(t-butylperoxy)butyrate (LUPEROX® PST); OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TBEC); OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC); O O-tert-butylperoxy-O-isopropyl-monoperoxycarbonate (LUPEROX® TBICM75); polyethertetrakis(tert-butylperoxycarbonate) [LUPEROX® JWEB-50]; di-tert-butyldiperoxyphthalate (LUPEROX® KDB); 2,5-dimethyl-2,5-di(benzoylperoxy)hexane (LUPEROX® 118); tert-butylperoxybenzoate (LUPEROX® (Registered Trademark) P); tert-amyl peroxybenzoate (LUPEROX® TAP); tert-butyl peroxyacetate (LUPEROX® 7); tert-amyl peroxyacetate (LUPEROX® 555); tert-butyl peroxyacetate (LUPEROX® 7M75); tert-butyl peroxyisobutyrate (LUPEROX® 80), 2-butanone peroxide (LUPEROX® DDM-9); or combinations thereof.

[0050] Preferred room-temperature stable peroxides are: hemiperoxyketals; peroxyesters, monoperoxycarbonates; peroxyketals; 1-tert-amylperoxy-1-methoxycyclohexane; tert-butylperoxyacetate; tert-amylperoxyacetate; tert-butylperoxybenzoate; 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane; 1,1-di(tert-amylperoxy)cyclohexane; 1,1-di(1-butylperoxy)cyclo Hexane; 2,2-di(tert-butylperoxy)butane; OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amylperoxy-O-isopropyl-monoperoxycarbonate; OO-tert-butylperoxy-O-isopropylmonoperoxycarbonate; polyethertetrakis(tert-butylperoxycarbonate); or tert-amylperoxybenzoate.

[0051] Preferred room-temperature stable organic peroxides are: 1-tert-amylperoxy-1-methoxycyclohexane (LUPEROX® V10); 1,1-di(t-butylperoxy)-3,3,5-trimethylcyclohexane (LUPEROX® 231); 1,1-di(tert-butylperoxy)cyclohexane LUPEROX® 331M80; tert-amylperoxybenzoate (LUPEROX® TAP); tert-butylperoxybenzoate (LUPEROX® P); OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TBEC). ;OO-tert-butylperoxy-O-isopropyl-monoperoxycarbonate (LUPEROX® TBICM75);OO-tert-amylperoxy-O-isopropyl-monoperoxycarbonate (LUPEROX® TAICM75);OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC);polyethertetrakis(t-butylperoxycarbonate) [LUPEROX® JWEB-50];tert-amylperoxyacetate;n-butyl 4,4-di(tert-butylperoxy)valerate (LUPEROX® 230).

[0052] More preferred room-temperature stable organic peroxides are: tert-amyl peroxybenzoate (LUPEROX® TAP); tert-butyl peroxybenzoate (LUPEROX® P); OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TBEC); OO-tert-butyl peroxy-O-isopropyl-monoperoxycarbonate (LUPEROX® TBICM75); OO-tert-amyl peroxy-O-isopropyl-monoperoxycarbonate (LUPEROX® TAICM75); OO -tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC); and polyethertetrakis(t-butylperoxycarbonate) [LUPEROX® JWEB-50]; 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane; 1,1-di-tert-amylperoxyhexane (LUPEROX® 531M80); 1,1-di(tert-butylperoxy)cyclohexane LUPEROX® 331M80; and 2,2-di(tert-amylperoxy)butane LUPEROX® 520.

[0053] Further preferred room-temperature stable organic peroxides are: tert-amyl peroxybenzoate (LUPEROX® TAP); tert-butyl peroxybenzoate (LUPEROX® P); OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TBEC); OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC); 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane LUPEROX® 231; 1,1-di(tert-butylperoxy)cyclohexane LUPEROX® 331M80; and 1,1-di-tert-amylperoxyhexane (LUPEROX® 531M80).

[0054] Another type of organic peroxide is the non-room-temperature stable organic peroxide, which is liquid below 10°C. These peroxides are not stable at room temperature in their liquid state and must be stored in a refrigerator or freezer at a temperature lower than room temperature. Because these less thermally stable organic peroxides have lower 1-hour and 10-hour half-life temperatures than the room-temperature stable organic peroxides contained in the composition, they must be stored in a temperature-controlled refrigerator or freezer. For example, these non-room-temperature stable organic peroxides have a 1-hour half-life temperature of less than 100°C, less than 98°C, less than 95°C, less than 90°C, less than 88°C, or less than 75°C. These non-room-temperature stable peroxides may have a 10-hour half-life temperature of 78°C or less, 75°C or less, 70°C or less, or 60°C or less. The most preferred non-room-temperature stable peroxides have a 1-hour half-life temperature between less than 96°C and greater than 85°C, and a 10-hour half-life temperature between less than 78°C and greater than 65°C. According to some embodiments, “non-room temperature stable” organic peroxides may have a recommended maximum storage temperature of no more than 10°C or no more than 5°C for long-term storage of up to 6 months.

[0055] For example, in the case of tert-butylperoxy-2-ethylhexanoate (LUPEROX® 26), it is recommended to keep the maximum storage temperature in the original container below 50°F (10°C) to maintain a peroxide concentration loss of less than 2% for 6 months. Trigonox® 421 (1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate) has a maximum storage temperature of 41°F (5°C) to maintain a peroxide concentration loss of less than 2% for 6 months. Therefore, various non-room temperature stable organic peroxides may have maximum recommended storage temperatures of 16°C or below, or 10°C, or 5°C, or 0°C, or -5°C, or -10°C, or 15°C or below, depending on the organic peroxide. According to certain embodiments of this disclosure, non-room-temperature stable organic substances present in the curable resin composition may have a 10-hour half-life temperature of 77°C or less, or 75°C, or 65°C, or 60°C, or 55°C, or 50°C or less. In yet another embodiment, the non-room-temperature stable organic peroxide has a peroxide concentration loss of 2% or less even after being stored at 10°C or below for 3, 6, or 9 months or more.

[0056] According to some embodiments, preferred non-room temperature stable organic peroxides have a temperature range of 78°C or less to 69°C or less for a 10-hour half-life and a temperature range of 95°C or less to 88°C or less for a 1-hour half-life. According to some embodiments, non-room temperature stored liquid peroxides can have a maximum storage temperature in the range of 16°C or less to 5°C or less.

[0057] Suitable classes of non-room-temperature stable organic peroxide formulations in liquid form requiring freezing (below 0°C) include the peroxydicarbonate and peroxyester classes of peroxides.

[0058] Non-limiting examples of suitable non-room-temperature stable organic peroxide formulations requiring refrigerated storage of liquids (above 0°C and below 20°C) include the diacyl and peroxyester classes of organic peroxides.

[0059] A non-limiting example of suitable non-room-temperature liquid organic peroxides is: di(n-propyl)peroxydicarbonate; di(sec-butyl)peroxydicarbonate; di(2-ethylhexylperoxydicarbonate); 3-hydroxy-1,1-dimethylbutylperoxyneodecanoate; 1,1-di(t-butylperoxy)cyclohexane; tert-butylperoxy-2-ethylhexanoate; α-cumylperoxyneodecanoate; tert-amylperoxyneodecanoate; tert-butylperoxyneodecanoate; tert-amylperoxypivalate; tert-butylperoxypivalate; 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane; tert-amylperoxy C-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575); tert-butylperoxy-2-ethylhexanoate (LUPEROX® 26); 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane (LUPEROX® 256); 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Trigonox® 421); tert-hexylperoxy-2-ethylhexanoate; 2-butanone peroxide (LUPEROX® DDM-9); or liquid forms of dibenzoyl peroxide, or combinations thereof.

[0060] Preferred non-room temperature organic peroxyesters include t-amylperoxy-2-ethylhexanoate (LUPEROX® 575), tert-butylperoxy-2-ethylhexanoate (LUPEROX® 26), 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane (LUPEROX® 256), 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Trigonox® 421), tert-hexylperoxy-2-ethylhexanoate, liquid dibenzoyl peroxides, or combinations thereof.

[0061] To avoid any ambiguity, when dibenzoyl peroxide (also known as benzoyl peroxide) is in a liquid state (such as dissolved in a suitable solvent), it is classified as a non-room-temperature stable organic peroxide with a 1-hour half-life temperature of 91°C (i.e., below 100°C). In the solid state, dibenzoyl peroxide is only storage stable at 38°C (above room temperature).

[0062] Non-room-temperature stable organic peroxides include tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575); 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Trigonox® 421); 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane (LUPEROX® 256); and more preferably tert-butylperoxy-2-ethylhexanoate and tert-hexylperoxy-2-ethylhexanoate alone or in combination.

[0063] The most preferred non-room-temperature stable organic peroxides are tert-butylperoxy-2-ethylhexanoate; tert-amylperoxy-2-ethylhexanoate; and 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane, either alone or in combination. A preferred combination of room-temperature stable peroxides and non-room-temperature stable peroxides is selected from the following preferred room-temperature stable peroxides: tert-amyl peroxybenzoate (LUPEROX® TAP); tert-butyl peroxybenzoate (LUPEROX® P); OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TBEC); LUPEROX® JWEB-50; OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC); 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane; 1,1-di-tert-amyl peroxyhexane (LUPEROX® 531M80); and 1,1-di-tert-butylperoxycyclohexane (LUPEROX® 331M80).

[0064] Preferred non-room-temperature stable peroxides can be selected from the following: tert-butylperoxy-2-ethylhexanoate; tert-amylperoxy-2-ethylhexanoate; 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate; and 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane.

[0065] In one embodiment, the non-room-temperature stable peroxide does not need to contain perketal.

[0066] In one embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of 1,1-di(tert-butylperoxy)cyclohexane (LUPEROX® 331M80) and tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575).

[0067] In another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of tert-butylperoxybenzoate and 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane.

[0068] In another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane and tert-butylperoxy-2-ethylhexanoate.

[0069] In another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of 1,1-di-tert-butylperoxy-3,3,5-trimethylcyclohexane and tert-amylperoxy-2-ethylhexanoate.

[0070] In another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of tert-butylperoxybenzoate and 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate.

[0071] In yet another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of tert-butylperoxybenzoate and tert-butylperoxy-2-ethylhexanone.

[0072] In another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of tert-butylperoxybenzoate (LUPEROX® P) and tert-amylperoxy-2-ethylhexanonate (LUPEROX® 575).

[0073] In another embodiment, the combination of room-temperature stable peroxides and non-room-temperature stable peroxides is configured by using a blend of tert-amylperoxybenzoate and tert-butylperoxybenzoate in combination with a blend of tert-butylperoxy-2-ethylhexanoate and tert-amylperoxy-2-ethylhexanoate.

[0074] In yet another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate and tert-butylperoxy-2-ethylhexanonate.

[0075] In yet another embodiment, the combination of a room-temperature stable peroxide and a non-room-temperature stable peroxide includes a blend of OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate and tert-amylperoxy-2-ethylhexanonate.

[0076] In yet another embodiment, the combination of room-temperature stable peroxide and non-room-temperature stable peroxide includes a blend of OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate and tert-amylperoxy-2-ethylhexanonate. According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of tert-butylperoxybenzoate (LUPEROX® P) and 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane (LUPEROX® 256).

[0077] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TBEC) and 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)-hexane (LUPEROX® 256).

[0078] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of tert-butylperoxybenzoate (LUPEROX® P) and tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575).

[0079] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC) and tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575).

[0080] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of tert-butylperoxyacetate (LUPEROX® 7M75) and tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575).

[0081] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of polyether poly(t-butyl)-peroxycarbonate (LUPEROX® JWEB50) and tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575).

[0082] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate (LUPEROX® TAEC) and tert-butylperoxy-2-ethylhexanoate (LUPEROX® 26).

[0083] According to one embodiment, a combination of room-temperature and non-room-temperature stable peroxides includes a blend of tert-butylperoxybenzoate (LUPEROX® P) and tert-butylperoxy-2-ethylhexanoate (LUPEROX® 26).

[0084] According to one embodiment, the combination of room-temperature and non-room-temperature stable peroxides includes a blend of 2-butanone peroxide (LUPEROX® DDM-9) and tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575).

[0085] According to one embodiment, at least one non-room temperature stable organic peroxide includes at least one of the following: diacyl peroxide, ketone peroxide; hydroperoxide; peroxydicarbonate; peroxyester; diacyl peroxide; di(n-propyl) peroxydicarbonate; di(sec-butyl) peroxydicarbonate; di(2-ethylhexyl peroxydicarbonate); 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate; α-cumyl peroxyneodecanoate; tert-amyl peroxyneodecanoate; α-cumyl peroxyneodecanoate; tert-butyl peroxyneodecanoate; tert-amyl peroxypivalate; tert-butyl Perperoxypivalate; 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane; tert-amylperoxy-2-ethylhexanoate; 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate; tert-hexylperoxy-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; dilauryl peroxide solution; or dibenzoyl peroxide solution; preferably tert-amylperoxy-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; tert-hexylperoxy-2-ethylhexanoate; or 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate.

[0086] According to yet another embodiment, at least one non-room temperature stable organic peroxide includes at least one of the following: peroxydicarbonate; peroxyester; diacyl peroxide; tert-amylperoxy-2-ethylhexanoate (LUPEROX® 575), tert-butylperoxy-2-ethylhexanoate (LUPEROX® 26); 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane (LUPEROX® 256), 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Trigonox® 421); tert-hexylperoxy-2-ethylhexanoate; dilauryl peroxide solution, or dibenzoyl peroxide solution.

[0087] The curable resin composition is preferably composed of a total amount of organic peroxides effective in achieving substantially complete curing (polymerization) of the curable resin present in the composition under selected curing conditions. Such amounts can vary considerably depending on the selected organic peroxides, the components of the activator system (such as the specific metal salts and thiol-functionalized organic compounds present, and their relative amounts), the reactivity of the curable resin, the desired curing profile, and other parameters. Generally speaking, however, in various embodiments of the present disclosure, the curable resin composition may be advantageously composed of at least 0.05%, at least 0.1%, at least 0.15%, at least 0.2%, at least 0.25%, at least 0.3%, at least 0.35%, or at least 0.4%, or at least 0.6% or more of organic peroxides, based on the weight of the curable resin. An advantage of the embodiments of the present disclosure is that, in at least certain embodiments of the present disclosure, relatively small amounts of organic peroxides can be used due to the accelerating effect when accelerator salts and thiol-functionalized organic compounds are used in combination. Therefore, the curable resin composition may contain organic peroxides in a total amount of 2% by weight or less, 1.5% by weight or less, and 1% by weight or less, based on the weight of the curable resin.

[0088] According to other embodiments, the curable resin composition may contain more than 2% by weight of organic peroxides in total, based on the weight of the curable resin. For example, the curable resin composition may contain up to 5% by weight of organic peroxides in total, based on the weight of the curable resin. According to some embodiments, the curable resin composition may contain up to 5, 4.75, 4.5, 4.25, 4, 3.75, 3.5, 3.25, 3, 2.75, 2.5, 2.25, or up to 2% by weight of organic peroxides in total, based on the weight of the curable resin.

[0089] The weight ratio of room-temperature stable liquid organic peroxide to non-room-temperature stable liquid peroxide can be changed as needed to give the curable resin composition the target curing profile. For example, the weight ratio of room-temperature stable organic peroxide to non-room-temperature stable organic peroxide may be 4:1 to 1:4, 3:1 to 1:3, 2:1 to 1:2, or 1:1, or preferably 3:1 to 1:1, or 2:1 to 1:1, or 1:2 to 1:3, or 3:1 to 1:4, but higher or lower weight ratios may also be used. For example, the weight ratio of room-temperature stable organic peroxide to non-room-temperature stable organic peroxide may be 10:1 to 1:10, 9:1 to 1:9, 8:1 to 1:8, 7:1 to 1:7, 6:1 to 1:6, 5:1 to 1:5, or 4:1 to 1:4.

[0090] One advantage of the liquid organic peroxide formulations useful in embodiments of this disclosure is that it is not necessary to dilute the organic peroxide / formulation / blend with styrene to prepare a well-dispersed liquid before impregnating it into a substrate to be mixed with a resin and cured. Therefore, the liquid organic peroxides, liquid peroxide formulations, and liquid organic peroxide blends useful in embodiments of this disclosure may contain less than 30% by weight, less than 20% by weight, less than 10% by weight, less than 5% by weight, less than 3% by weight, less than 2% by weight, less than 1%, less than 0.5%, less than 0.1%, or 0% by weight of styrene, based on the total weight of the organic peroxide blend. By excluding styrene, it is not necessary to store and handle styrene separately, no extra processing steps are required, and it is more environmentally friendly.

[0091] Metal salts (accelerators / activators / promoters) The curable resin compositions of embodiments of this disclosure may contain one or more metal salts. Such salts, accelerators, or promoters promote or activate the decomposition of one or more organic peroxides present in the curable resin composition, thereby accelerating the curing of the curable resin composition by the organic peroxides. While not bound by any particular theory, it is thought that such metal salts may react with thiol-functionalized organic compounds present in the curable resin composition to form a complex that is actually a species that promotes curing at high temperatures, or that the thiols may assist in the decomposition of the peroxides and the curing of the resin.

[0092] Suitable metal salts include salts of metals selected from the group consisting of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, and Pt. The anionic portion of the salt may be a halide, nitrate, sulfate, or carboxylate. Other suitable anions include, for example, lactic acid, acetic acid, hexanoic acid, or naphthenic acid. Halide salts of transition metals are preferred, and especially chloride salts of transition metals are preferred.

[0093] According to certain embodiments of the present disclosure, at least one metal salt may comprise at least one transition metal halide. In a particularly preferred embodiment, the at least one metal salt comprises at least one zinc, copper, or lithium halide, such as zinc chloride, lithium chloride, or copper(II) chloride. Zinc chloride, lithium chloride, copper(II) chloride, or a combination thereof is preferred. Zinc chloride and / or lithium chloride is more preferred. Zinc chloride is particularly preferred as the metal salt used in embodiments of the present disclosure.

[0094] Typically, a curable resin composition contains an amount of metal salt that is effective in reducing the curing time of the curable resin composition compared to the curing time observed in the absence of metal salt. Such an amount varies depending on many factors, but in various embodiments of the present disclosure, the metal salt is present in an amount such that, based on the weight of the curable resin in the curable resin composition, the total amount of metals selected from the group consisting of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, and Pt is at least 5, 10, 20, 30, 40, or 50 ppm. In other embodiments, the curable composition contains an amount of metal salt that provides such metals in the curable resin composition at a concentration of 500, 400, 300, 200, or 100 ppm or less, based on the weight of the curable resin.

[0095] Thiol-functionalized organic compounds The curable resin compositions of this disclosure may contain at least one thiol-functionalized organic compound. Such a thiol-functionalized organic compound can be characterized as an organic compound containing at least one thiol (-SH) functional group per molecule, which, when used according to embodiments of this disclosure, can increase the curing rate of the curable resin composition. According to certain embodiments of this disclosure, the at least one thiol-functionalized organic compound includes at least one thiol-functionalized organic compound containing two or more thiol functional groups per molecule. In one embodiment of this disclosure, the thiol group in the thiol-functionalized organic compound may be one or more aliphatic thiol groups (each thiol group is bonded to an aliphatic carbon atom). In yet another embodiment, the thiol group is a primary aliphatic thiol group or is a primary aliphatic thiol group. The at least one thiol-functionalized organic compound may contain an α-mercaptoacetic acid or β-mercaptopropionic acid ester of at least one alcohol. The alcohol may be a polyhydric alcohol containing two or more hydroxyl groups per molecule, such as glycol; trimethylolpropane; or pentaerythritol. Examples of suitable thiol-functionalized organic compounds include dipentene dimercaptan; ethylcyclohexyl dimercaptan; ethylene-1,2-bis-3-mercaptoacetate; ethylene-1,2-bis-3-mercaptopropionate; 1,2,3-propanetrithiol; 1,2,6-hexanetrithiol; pentaerythritol thiol; pentaerythritol tetrakis(2-mercaptoacetate); pentaerythritol tetrakis(3-mercaptopropionate); trimethylolpropanetris(3-mercaptopropionate); 1,1,1-propanetriyltris(mercaptoacetate); and formula: R-(R'-CH(OH)-CH2-SH) nThis includes thiol derivatives (where R is a linear alkyl group having 3 to 30 carbon atoms, R' is a linear alkylene group having 3 to 30 carbon atoms, and n is an integer from 2 to 6). Suitable thiol-functionalized organic compounds for use in embodiments of this disclosure also include the thiol compounds disclosed in U.S. Patent Publication No. 5,310,826, the entirety of which is incorporated herein by reference for all purposes. Combinations of two or more different thiol-functionalized organic compounds may also be used.

[0096] The most preferred thiol-functionalized organic compounds include trimethylolpropanetris(3-mercaptopropionate); pentaerythritoltetrakis(2-mercaptoacetate); pentaerythritoltetrakis(3-mercaptopropionate); and 1,1,1-propanetriyltris-(mercaptoacetate). Of these, pentaerythritoltetrakis(3-mercaptopropionate) is even more preferred.

[0097] The amount of thiol-functionalized organic compounds present in the curable resin composition can be changed as desired or as necessary, depending on the activity of the thiol-functionalized organic compounds, the types and reactivity of other components in the curable resin composition, the desired curing profile, and other factors. Generally speaking, however, the curable resin composition may contain thiol-functionalized organic compounds in a total amount of at least 0.005% by weight, at least 0.01% by weight, or at least 0.02% by weight, but not exceeding 2% by weight, 1% by weight, or 0.5% by weight, based on the weight of the curable resin in the curable resin composition.

[0098] The weight ratio of the metal salt to the thiol-functionalized organic compound can be modified as appropriate or as desired, depending on several factors, including the specific metal salt and thiol-functionalized organic compound used, as well as the target curing profile of the curable resin composition. However, according to certain non-limiting aspects of this disclosure, this weight ratio can vary from 1:1 to 1:10.

[0099] solvent The curable resin compositions of embodiments of this disclosure may further contain at least one solvent. Non-limiting examples of suitable solvents include alcohols, glycols, or glycol ethers.

[0100] Suitable alcohols are alkyl monoalcohols having 1 to 30 carbon atoms. Non-limiting examples of suitable alcohols include tert-butyl alcohol, tert-amyl alcohol, ethyl alcohol, or isopropyl alcohol.

[0101] Non-limiting examples of suitable glycols include ethylene glycol, propylene glycol, butylene glycol, dipropylene glycol, diethylene glycol, triethylene glycol, neopentyl glycol, pentaerythritol, or combinations thereof. Dipropylene glycol is preferred. As mentioned above, these glycols can react with certain curable resin systems.

[0102] Non-limiting examples of suitable glycol ethers include methoxyethanol, ethoxyethanol, butoxyethanol, methoxypropanol, diethylene glycol monobutyl ether (DGMBE), or combinations thereof. Glycol ethers are preferred solvents in curable resin compositions, with diethylene glycol monobutyl ether (DGMBE) being the most preferred.

[0103] Other ingredients The above-mentioned curable resins, peroxides, accelerator salts, and thiol-functionalized organic compounds can be combined with any of the other additives conventionally used in curing resin technology, such as fillers, fibers, pigments, viscosity reducers, inhibitors (e.g., inhibitors of degradation by oxidation, heat, and / or ultraviolet light), lubricants, thixotropic agents, auxiliary agents, and accelerators.

[0104] Examples of suitable fibers include glass fibers, carbon fibers, polymer fibers (e.g., aramid fibers), natural fibers, and combinations thereof. The fibers may be in any suitable form, including mats, tows, and other forms known in the art.

[0105] Suitable fillers include talc, calcium carbonate, quartz, sand, silica, aluminum trihydrate, magnesium hydroxide, chalk, clay, carbon black, titanium dioxide, lime, as well as organic fillers such as thermoplastics and rubber, and mixtures thereof.

[0106] In one embodiment, the present disclosure relates to an organic peroxide composition comprising the following blend: ·Non-room temperature stable organic peroxide; • Room temperature stable organic peroxides; • At least one transition metal halide salt dissolved in an alcohol, glycol, or glycol ether; • At least one thiol-functionalized organic compound; Here, the organic peroxide composition is stable at room temperature for at least 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, or up to 24 hours.

[0107] In another embodiment, the disclosure relates to an organic peroxide composition comprising: a non-room-temperature stable peroxide, tert-amylperoxy-2-ethylhexanoate LUPEROX® 575 or 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Trigonox® 421); a room-temperature stable peroxide, tert-butylperoxybenzoate LUPEROX® P; a metal halide, preferably ZnCl2, dissolved in a glycol ether, preferably diethylene glycol monobutyl ether; and a thiol compound, preferably pentaerythritol tetrakis(3-mercaptopropionate). The organic peroxide composition of this embodiment is stable at room temperature for at least 1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, or up to 24 hours.

[0108] Formulation of curable resin compositions Preparation of curable resin compositions according to embodiments of the present disclosure can be carried out using any suitable method. For example, a liquid and / or fluid curable resin composition can be formed by mixing at room temperature (e.g., 20°C to 30°C) at least one curable resin; at least one room-temperature stable organic peroxide that is liquid at 25°C; at least one liquid non-room-temperature stable peroxide that is liquid at 10°C; at least one salt of at least one metal comprising at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, and Pt; at least one thiol-functionalized organic compound; and at least one solvent optionally comprising at least one alcohol, glycol, or glycol ether, which is then heated to a temperature effective for curing the curable resin composition.

[0109] Alternatively, it is possible to pre-mix specific components of the curable resin composition to prepare separate storage stability components, and then combine these when it is desired to prepare the curable resin composition, thereby producing a cured composition from the curable resin composition.

[0110] For example, one embodiment of the present disclosure provides a system useful as a curing system for curable resins. Such a system may comprise a first component and a second component. The first component may comprise at least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher over one hour; and at least one non-room-temperature stable peroxide that is liquid at 10°C or lower, has a half-life temperature of less than 100°C over one hour, and is optionally substantially styrene-free or optionally styrene-free. The second component may comprise at least one salt of at least one metal selected from the group consisting of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, and Pt; at least one thiol-functionalized organic compound; and optionally at least one solvent comprising at least one alcohol, glycol, or glycol ether. The second component may be formulated in the form of a solution or dispersion, in which case the solvent or dispersant, or a combination of solvents or dispersants, is used to dissolve the promoter salt and the thiol-functionalized organic compound. To prepare a curable resin composition, the first and second components are combined in a desired proportion with a third component containing at least one curable resin.

[0111] In another embodiment of the present disclosure, the curable resin, metal salt, and thiol-functionalized organic compound are pre-mixed several days or weeks before the addition of the peroxide to form a curable resin composition, thereby initiating the actual curing process. This enables the commercial production and sale of compositions that already contain a metal salt / thiol system and can be provided simply by combining them with the peroxide described herein to provide the curable resin compositions of the embodiments of the present disclosure.

[0112] In yet another embodiment, a curing system is provided comprising: at least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; at least one non-room-temperature stable peroxide that is liquid at 10°C or lower and has a half-life temperature of less than 100°C; at least one salt of at least one metal selected from the group consisting of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, and Pt; at least one thiol-functionalized organic compound; and optionally, at least one solvent comprising at least one alcohol, glycol, or glycol ether. This system has storage stability despite the peroxide, thiol compound, and metal salt being contained in a single composition.

[0113] Another embodiment of the present disclosure is a curing system comprising: at least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; at least one non-room-temperature stable peroxide that is liquid at 10°C or lower and has a half-life temperature of less than 100°C; at least one salt of at least one metal selected from the group consisting of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, and Pt; at least one thiol-functionalized organic compound; and at least one solvent (glycol ether type solvent is preferred) comprising at least one of alcohol, glycol, or glycol ether. The system is storage stable even if the peroxide, thiol compound, metal salt, and at least one of alcohol, glycol, or glycol ether are included in a single composition.

[0114] In another embodiment, combinations of room-temperature and non-room-temperature stable peroxides include a blend of tert-butyl peroxybenzoate (LUPEROX® P), tert-amyl peroxy-2-ethylhexanonate (LUPEROX® 575), ZnCl2, PETMP (pentaerythritol tetrakis (3-mercaptopropionate)), and diethylene glycol monobutyl ether (DGMBE) as an optional solvent.

[0115] Furthermore, embodiments of the present disclosure also envision a two-component system comprising a first component and a second component, wherein the first component comprises at least one pre-accelerated curing resin (a combination of at least one curable resin, at least one metal salt, and at least one thiol-functionalized organic compound), and the second component comprises a mixture of different organic peroxides used in embodiments of the present disclosure. This second component may include room-temperature stable and non-room-temperature stable peroxides, as well as the metal salts, thiol compounds, and solvents disclosed herein. As used herein, the term “two-component system” means a system in which two components (A and B) are physically separated from each other (e.g., in separate cartridges, compartments, totes, drums, or other containers) and that components A and B are physically combined (mixed) when the system is used to form a curing resin.

[0116] In particularly preferred embodiments of this disclosure, a curing system is provided which includes the following: i) The first component includes the following: At least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; and At least one non-room temperature stable organic peroxide that is liquid below 10°C and has a half-life temperature of less than 100°C; and ii) Second component including the following: A salt of at least one metal comprising at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; At least one thiol-functionalized organic compound; and Optionally, at least one solvent comprising at least one of an alcohol, glycol, or glycol ether.

[0117] The first component may optionally not contain styrene.

[0118] Uses of curable resin compositions The curable resin compositions of the embodiments of this disclosure are particularly useful in applications where a long exposure time at ambient temperature (e.g., room temperature or 25°C) is desired, but a relatively short curing time is desired when the curable resin composition is heated to a high temperature (e.g., at least 50°C, 60°C, 70°C, or 80°C, but typically 250°C, 240°C, 230°C, 220°C, 210°C, or 200°C or lower). In various embodiments of this disclosure, the curing time (i.e., the time the curable resin composition is heated) is at least 0.5, 1, 2, 3, 4, or 5 minutes, but not exceeding 10 hours, 9, 8, 7, 6, 5, 4, 3, 2, 1 hour, or 0.5 hours. For example, the curable resin composition can be heated for 1 minute to 20 minutes. The heating of the curable resin composition can be performed at a temperature and time effective in achieving the reaction of at least 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or 100% of the monomers initially present in the curable resin. The monomer reaction rate can be calculated by analytically measuring the unreacted residual monomers remaining in the curable resin as part of the total composition.

[0119] Such applications include, for example, composite systems that impregnate a matrix (e.g., a matrix of fibers such as glass fibers, polymer fibers, or carbon fibers in sheet or tow form) with a curable resin composition to form an impregnated matrix, and then form and cure the impregnated matrix into a desired configuration to provide a composite product.

[0120] For example, the curable resin compositions of embodiments of this disclosure can be used in so-called “in-situ curing” piping systems. In-situ curing pipes (CIPPs) are one of several trenchless repair methods used to repair existing pipelines such as water, sewer, gas, and chemical pipelines. CIPPs are jointless, seamless pipe-in-pipe systems that can repair pipes of various diameters and configurations, thus eliminating the need to excavate existing pipelines for repair or replacement. In the context of this disclosure, a resin-impregnated liner can be obtained by impregnating a flexible liner, including a polyester fabric, fiberglass cloth, or other type of fabric (woven or nonwoven), with a curable resin composition, and then inverting or pulling this liner into the damaged pipe (for example, as described in U.S. Patent Publications No. 4,009,063 and No. 4,064,211; the entire disclosures of each of these patents are incorporated herein by reference for all purposes). The liner may be in the form of a laminate comprising a layer of nonwoven fabric coated with a thermoplastic sheet material, wherein the nonwoven fabric is impregnated with a curable resin composition. The resin-impregnated liner can be inverted using water or air pressure. After being placed in a damaged pipe, the resin-impregnated liner can be heated by any suitable method to a temperature effective in initiating the curing of the curable composition. For example, the resin-impregnated liner in the damaged pipe can be heated by introducing hot water or steam. In some cases, the ambient temperature inside the damaged pipe containing the resin-impregnated liner may become high enough to achieve the desired curing. Once cured, the resin-impregnated liner becomes relatively hard and rigid and can function as a pipe for transporting liquids, gases, etc. The long open time characteristic of the curable resin composition of the embodiments of this disclosure offers a clear advantage in such field-curing piping systems, as the resin-impregnated liner can maintain its flexibility and workability over a long period and can be adequately prepared before actual deployment, as long as it is kept at a temperature lower than the temperature at which curing of the curable resin begins to occur at a significant rate.While resin-impregnated liners can be refrigerated to further extend their open time, in certain embodiments of this disclosure, such refrigeration is not necessary because the curable resin composition has a sufficient open time (e.g., 15, 30, 45, 60 minutes or more) even at ambient temperatures of 20-25°C.

[0121] Accordingly, one embodiment of the present disclosure includes a resin-impregnated liner comprising a liner impregnated with a curable resin composition according to any embodiment described herein. Further embodiments of the present disclosure provide a process for producing a resin-impregnated liner suitable for use in field-cured pipe methods, the process comprising impregnating a liner with a curable resin composition according to any embodiment described herein. Also embodiments of the present disclosure provide a method for lining a cavity of a passage or pipe having an inner surface, the method comprising: a) introducing a resin-impregnated liner into the cavity, wherein the resin-impregnated liner comprises a liner impregnated with a curable resin composition according to any embodiment described herein; and b) introducing steam or hot water into the inner opening of the resin-impregnated liner to press the resin-impregnated liner against the inner surface of the passage or pipe and activate the curing of the curable resin composition present in the resin-impregnated liner. The resin-impregnated liner is initially flexible but then hardens and becomes rigid within the passage or pipe.

[0122] The curable resin compositions of the embodiments of this disclosure are also useful in pultrusion processes. As is well known in the art, pultrusion is a process that combines a tension process and an extrusion process. A reinforcing structure, which may be a fiber, cloth, or other form, is continuously drawn from a spool or the like and impregnated with a matrix material. In the context of this disclosure, this matrix material may be one of the curable resin materials described herein. Such impregnation can be carried out, for example, in a wet bath. The reinforcing structure impregnated with the curable resin composition is formed into a final shape by drawing it through a heated die. The final curing of the composite material also usually occurs downstream of the die. The curable resin compositions of the embodiments of this disclosure are particularly suitable for use in such pultrusion processes because they have a long open time but a short curing time.

[0123] An example embodiment of such a pultrusion process is generally described as follows: Fibrous reinforcing material is held on a rack, spindle, or other suitable support. The fiber strands pass through a preform guide to bundle the fibers into preliminary groups, or the fibers are pre-bundled to form woven or braided strands. A tank is provided to hold a certain amount of curable resin composition in liquid form (as a resin bath), and the curable resin composition is maintained at a temperature at which curing does not occur at a significant rate. The reinforcing material, such as a tow formed from the fiber strands, is passed through the resin bath, allowing the curable resin composition to permeate the reinforcing material. The wet tow is drawn out through rollers and a second material guide, and the composite material is further formed. The composite tow is formed in a pultrusion die and cured by the action of one or more heaters. Composite products that can be manufactured by the pultrusion method include, for example, ladder components, door and window profiles, structural members, cable trays, tool handles, pipes; tubes; rebar; wind turbine blade components, panels, and the like.

[0124] In addition to the processes described above, the curable resin compositions of the embodiments of this disclosure are also useful in resin transfer molding processes. As is well known in the art, resin transfer molding consists of the process of placing a reinforcing material, such as a fiber mat, matrix, or preform, into a fitted mold tool. The tool is closed, and the curable resin is injected into the gaps, injecting the reinforcing material. Typically, the tool is heated, and curing is initiated while the tool is compressed at a high temperature. A further description of conventional resin transfer molding is found in U.S. Patent Publication No. 4,762,740, which is incorporated herein by reference in its entirety for all purposes. In one type of resin transfer molding, one half of the mold is a flexible bag or sheet known as a vacuum bag.

[0125] A schematic description of such a resin transfer molding process is as follows: Woven fibrous reinforcing material is draped into a matched mold tool or inserted as a preform. The tool is closed, and the curable resin is injected into the gap either in a fully pre-formed state or after multiple components have been mixed at the injection point. A heated mold compresses the resin / reinforcing system, and curing occurs. The mold is opened, the cured part is removed, and this process is repeated.

[0126] The curable resin compositions of the embodiments of this disclosure are also useful for producing prepreg sheets, tapes, or fabrics in which the curable resin composition is impregnated into a matrix of fibers (such as glass fibers, polymer fibers, or carbon fibers in the form of nonwoven or woven fabrics). Next, multiple layers of fiber matrices impregnated with the curable resin composition are arranged or layered so that the fibers of each layer are aligned in the same direction or in different directions, and then molded and cured by pressing or other types of compression while heating to form a cured composite material.

[0127] While embodiments are described in this specification to enable a clear and concise description, it is intended and understood that embodiments can be combined and separated in various ways without departing from the disclosure. For example, it is understood that all preferred features described herein are applicable to all aspects of the disclosure.

[0128] In some embodiments, this disclosure may be interpreted as excluding elements or process steps that do not substantially affect the basic and novel properties of the composition or process. Furthermore, in some embodiments, this disclosure may be interpreted as excluding elements or process steps not expressed herein.

[0129] While this disclosure is illustrated and described herein with reference to specific embodiments, it is not intended to be limited to the details shown. Rather, various modifications to the details can be made within the scope of the equivalents of the claims and without departing from this disclosure. [Examples]

[0130] The following materials were used in the examples. Base resin: UPR (unsaturated polyester resin) Aropol (registered trademark) 2036C (Isophthalic acid resin manufactured by Ashland). PETMP: Pentaerythritol tetrakis(3-mercaptopropionate). LUPEROX(registered trademark) 575: tert-butylperoxy-2-ethylhexanoate (Arkema). (Stable at room temperature, not at room temperature) LUPEROX (registered trademark) M520M50: 2,2-di(tert-amylperoxy)butane (Arkema) (room temperature stable) LUPEROX® 331M80:1,1-di(tert-butylperoxy)cyclohexane (Arkema) (room temperature stable) LUPEROX (registered trademark) 531M80:1,1-di(tert-amylperoxy)cyclohexane (Arkema) (room temperature stable) LUPEROX (registered trademark) P:tert-butylperbenzoate (Arkema) (room temperature stable) LUPEROX (registered trademark) TBEC: tert-butylperoxy-2-ethylhexyl carbonate (Arkema) (room temperature stable) DGMBE: Diethylene glycol monobutyl ether ZnCl2: Zinc chloride LiCl: Lithium chloride UPR: Unsaturated polyester resin

[0131] Example 1: Combination of non-room temperature stable peroxide and room temperature stable peroxide As shown in Table 1, formulations were prepared containing tert-butylperoxy-2-ethylhexanoate (LUPEROX® 575), zinc chloride (ZnCl2), and pentaerythritol tetramercaptopropionate (PETMP) in an uncured base resin.

[0132] [Table 1]

[0133] Table 1 shows a blend of UPR-based resin combined with PETMP (thiol-functionalized organic compound) and ZnCl2, to which 0.20 wt% of LUPEROX® 575 (non-room temperature organic peroxide) was added. Using this composition from Table 1 as a stock solution, and using a portion of this resin composition from Table 1, several different non-room temperature organic peroxide and room temperature peroxide combinations were created, as shown in Table 2.

[0134] Therefore, formulations containing non-room-temperature organic peroxides shown in Table 1 were combined with various additional room-temperature stable organic peroxides, as shown in Table 2. Each room-temperature stable peroxide was added to the resin, and the solvent in the peroxide formulation was corrected to achieve a final concentration of 0.20% by weight (based on pure peroxide). For example, LUPEROX® 520M50 is a room-temperature stable peroxide that is diluted to 50% by weight with mineral spirits. Therefore, 0.4% by weight of the LUPEROX® 520M50 peroxide formulation was required to obtain 0.2% by weight (based on pure peroxide). See Table 2.

[0135] [Table 2]

[0136] Organic peroxide blends added to the resins shown in Table 2 were cured, and the curing rate was observed by monitoring the exothermic temperature. UPR resins containing various peroxide blends from Table 2 were subjected to a standard SPI gel test in an 80°C oil bath, and the curing results for various organic peroxides are plotted in Figure 1.

[0137] Notably, all of the peroxides in Table 2, including the use of Luperox® 575 alone, were mixed with the novel accelerator systems of the embodiments of this disclosure shown in Table 1. The use of the accelerator solution resulted in a significantly faster curing profile for all peroxides shown in Figure 1, including the use of Luperox® 575 alone, compared to cases without the accelerator solution.

[0138] Without an accelerator solution, even the fast-curing, non-room-temperature (refrigerated) peroxide Luperox® 575 will have a slower curing rate. This is shown in Figure 2. For example, when performing a 60°C gel test with Luperox® 575 (non-room-temperature stable peroxide) without using an accelerator solution, the time to reach the exothermic peak is very long, and the peak is not reached until 60 minutes have passed.

[0139] In contrast, when Luperox® 575 is mixed with the accelerator solution of the present invention and tested at 60°C, the time to reach the exothermic peak is significantly reduced to just 23 minutes, as shown in Example 2, Figure 2.

[0140] Completely unexpectedly, as shown in Figure 1, using a more thermally stable (room-temperature stable organic peroxide) in combination with LUPEROX® 575 (non-room-temperature stable organic peroxide) resulted in a more desirable and comparable exothermic curing profile when curing UPR resin with zinc chloride metal salt and PETMP thiol-functionalized organic compounds, compared to using the less thermally stable LUPEROX® 575 alone. Specifically, as shown in Figure 1, the blends of [LUPEROX® TBEC and LUPEROX® 575] and [LUPEROX® 520 and LUPEROX® 575] unexpectedly provided a more desirable and faster curing profile than using LUPEROX® 575 alone. Note that LUPEROX® TBEC and LUPEROX® 520 are slower, more thermally stable, room-temperature stable peroxides. This result is highly unexpected because, when using a non-room-temperature stable peroxide (LUPEROX® 575) alone, it is expected to cure much faster than when Luperox® 575 is blended with a slower room-temperature stable peroxide.

[0141] Blends of [LUPEROX(registered trademark) P & LUPEROX(registered trademark) 575] and [LUPEROX(registered trademark) 331M50 & LUPEROX(registered trademark) 575] yielded comparable curing initiation times compared to using LUPEROX(registered trademark) 575 alone, but unexpectedly, the desired curing heat persisted for a longer period after 8 minutes of peak heat generation. A longer heat generation period allows for more complete curing.

[0142] The blend of [LUPEROX® 575 and LUPEROX® 531M80] reached its exothermic peak in approximately 9 minutes. This is 1 minute slower than when Luperox® 575 is used alone in the same accelerator system. However, it is important to note that the blend of [LUPEROX® 575 and LUPEROX® 531M80] mixed with the accelerator system of the present invention cures much faster than when the novel accelerator solution system of the present invention is not used.

[0143] Example 2: When Luperox® 575 (non-room temperature organic peroxide) is used alone with or without the novel accelerator system of the present invention. This demonstrates how the novel accelerator system of the present invention can accelerate the curing of unsaturated polyester resin (UPR) at 60°C when Luperox® 575 is used alone, compared to when no accelerator solution is used. See Figure 2. In a 60°C gel test, Luperox® 575 (non-room temperature organic peroxide) shows peak exothermic reaction in 60 minutes without the accelerator solution. However, when Luperox® 575 is mixed with the accelerator solution according to the embodiment of the present invention and tested at 60°C, peak exothermic reaction is achieved in just 23 minutes. A comparative graph is shown in Figure 2.

[0144] [Table 3]

[0145] Example 3: Organic peroxide blends containing transition metal salts and thiol-functionalized organic compounds. This example demonstrates the novelty of the accelerator solution of the present invention. This example suggests that a safe, one-component solution combining the accelerator solution of the embodiments of this disclosure with an organic peroxide can be unexpectedly produced. Producing a safe, one-component solution of an organic peroxide containing an accelerator solution is extremely rare, unexpected, and incredibly novel. Those skilled in the art will know that directly adding an accelerator system to an organic peroxide is extremely dangerous, as it is expected to cause highly dangerous spontaneous decomposition of the organic peroxide. Thus, the ability to produce a safe solution of an organic peroxide containing an accelerator solution is extremely novel and provides customers with the safety that even if the accelerator blend is accidentally mixed with the organic peroxide, severe decomposition will not occur.

[0146] A room-temperature stable mixture was prepared, comprising a non-room-temperature stable peroxide, a room-temperature stable peroxide, and an accelerator system according to one embodiment of the present invention, which includes a mixture of DGMBE, ZnCl2, and PETMP.

[0147] Figure 3 compares the high-temperature stability at 30°C of a (2:1) weight-ratio mixture of tert-butylperoxybenzoate (Luperox® P, room-temperature stable organic peroxide) and tert-amylperoxy-2-ethylhexanoate (Luperox® 575, non-room-temperature stable organic peroxide). This peroxide mixture was evaluated with and without the novel accelerator solution of the present invention. (Note: Unsaturated polyester resin was not used in this example.) The accelerator solution used in the embodiment of this disclosure was added directly to the organic peroxide compound under ambient conditions, which is unusual as those skilled in the art would expect the peroxide to decompose rapidly. Furthermore, it was confirmed that the peroxide composition and accelerator package maintained unexpected high-temperature stability (non-decomposition) even after being held in a 30°C water bath for 4 hours.

[0148] Specifically, two glass test tubes were prepared by adding a total weight of 0.9 grams of the peroxide mixture to each test tube. This blend had a weight ratio of tert-butylperoxybenzoate to tert-amylperoxy-2-ethylhexanoate of 2:1. 0.15 grams of an accelerator solution was also added to one of these test tubes. The composition of this accelerator mixture was 86.5% DGMBE, 11% PETMP, and 2.5% ZnCl2. The accelerator solution was added directly to the pure peroxide blend. Surprisingly, no reaction or immediate decomposition occurred at laboratory room temperature of 73°F (22.7°C). This was completely unexpected. Those skilled in the art would have expected the peroxide to decompose immediately.

[0149] To further investigate the peroxide mixtures with and without the accelerator solution, both test tubes were placed in a water bath set to 30°C (86°F) and held at that high temperature for 4 hours. The results in Figure 3 show that no visible signs of peroxide decomposition were observed in either the peroxide mixture without the accelerator solution or the peroxide mixture with the accelerator solution. This data indicates that the addition of the novel accelerator solution to the peroxide mixture unexpectedly resulted in the same thermal stability as the peroxide mixture without the accelerator solution. Therefore, this data indicates that an unexpectedly safe one-component solution can be created by combining organic peroxides with the novel accelerator solution of the present invention.

[0150] Furthermore, after 4 hours at 30°C, these two solutions were removed from the water bath and placed on a heating block. The temperature of the heating block rose at a rate of 4°C per minute. Referring to Figure 3, the heat generated by both solutions was approximately the same, indicating that the mixture of the accelerator solution and the organic peroxide was still effective.

[0151] In summary, the blend of room-temperature stable organic peroxides and non-room-temperature stable organic peroxides containing the novel accelerator solution of the present invention has been demonstrated to exhibit good thermal stability along with good peroxide decomposition performance at high temperatures. The inventors have also demonstrated that a blend of non-room-temperature stable peroxides and room-temperature stable peroxides, further blended with the accelerator solution of the embodiments of this disclosure, is surprisingly as stable as the peroxide blend without the accelerator solution.

[0152] This data demonstrates the completely unexpected ambient temperature (22.7°C) stability and high temperature stability of the pure peroxide blend, including the accelerator system used in the implementation of embodiments of this disclosure.

[0153] Comparative Example 4: Decomposition of organic peroxides at room temperature and ZnCl 2 Comparison with the decomposition of the same organic peroxide at room temperature using only this compound. The rapid thermal decomposition test was performed by placing approximately 1 gram of pure tert-butyl perbenzoate (LUPEROX® P) in one test tube. The same 1 gram of organic peroxide was placed in a second test tube along with 0.02 grams of zinc chloride (ZnCl2). The two test tubes were placed in a block heated at a rate of approximately 4°C / min. This allowed for a comparison of the temperatures at which tert-butyl perbenzoate (LUPEROX® P) decomposes. The results are shown in Figure 4 below. Figure 4 shows that ZnCl2 destabilizes the organic peroxide, causing exothermic reaction faster than the pure organic peroxide, as expected.

[0154] Comparative Example 5: Comparison of the decomposition of an organic peroxide at room temperature with the decomposition of the same organic peroxide at room temperature combined with the novel accelerator solution of the present invention. The accelerator solution of the present invention: 86.5 wt% DGMBE, 11 wt% PETMP, 2.5 wt% ZnCl2

[0155] The room-temperature organic peroxide Luperox® P (tert-butyl perbenzoate) selected for this example was the same peroxide used in Example 4. In this test, approximately 1 gram of Luperox® P stock solution was placed in one test tube. In a second test tube, approximately 1 gram of Luperox® P stock solution and 0.20 grams of accelerator solution were added. This amount of accelerator solution added 0.005 grams of ZnCl2 to 1 gram of Luperox® P peroxide. (Note: PETMP is also included in the novel accelerator solution of this invention.) Both solutions were heated at a rate of 4°C per minute to rapidly decompose the organic peroxide. (Figure 5)

[0156] The solid line in Figure 5 shows that pure Luperox® P mixed with the novel accelerator solution of the present invention exhibited surprisingly superior thermal stability compared to pure Luperox® P peroxide without the novel accelerator solution of the present invention (dashed line). Thus, quite unexpectedly, it is shown that by using the teachings of the embodiments of this disclosure, it is possible to create a stable room-temperature peroxide solution containing the accelerator.

[0157] Example 6: Evaluation of LiCl (instead of ZnCl2) for promoting room-temperature organic peroxides to cure an unsaturated polyester resin at 80°C in an embodiment of the present invention.

[0158] [Table 4]

[0159] The lithium chloride accelerator solution contained 88 wt% diethylene glycol monobutyl ether (DGMBE), 10 wt% PETMP, and 2 wt% lithium chloride.

[0160] Regarding the curing of UPR, a standard gel test was performed at 80°C, comparing formulation #1, which combined 2.50 wt% Luperox® P and 0.50 wt% of the novel accelerator solution of the present invention (using LiCl), with formulation #2, which used 2.50 wt% Luperox® P without using an accelerator solution containing LiCl. The results plotted in Figure 6 show that the novel LiCl-containing accelerator solution of the present invention readily accelerated Luperox® P, resulting in very rapid curing of the unsaturated polyester resin.

[0161] Example 7: Promotion of single room-temperature organic peroxides In this example, a gel test was performed at 60°C to compare the curing performance of unsaturated polyester resins obtained by adding Luperox® P or the novel ZnCl2-based accelerator solution of the present invention to Luperox® P. The formulations used in this test are shown in Table 5.

[0162] [Table 5]

[0163] The accelerator solution consisted of 86.5% DGMBE, 11% PETMP, and 2.5% ZnCl2.

[0164] As shown in Figure 7, the formulation containing the novel accelerator solution of the present invention generates heat and hardens within 30 minutes. In comparison, the formulation without any accelerator solution showed no signs of an exothermic reaction for more than 2 hours.

Claims

1. A curable resin composition, a) At least one curable resin that can be cured by a liquid organic peroxide; b) At least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; c) Optionally, at least one non-room temperature stable organic peroxide that is liquid at 10°C or below and has a half-life temperature of less than 100°C; d) At least one salt of at least one metal, including at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; e) at least one thiol-functionalized organic compound; and f) Optionally, at least one solvent comprising at least one alcohol, glycol, or glycol ether; A curable resin composition containing [the specified ingredient].

2. The curable resin composition according to claim 1, further comprising (c) a non-room temperature stable organic peroxide.

3. The curable resin composition according to claim 1 or 2, wherein the at least one thiol-functionalized organic compound comprises at least one thiol-functionalized organic compound having two or more thiol functional groups.

4. The curable resin composition according to any one of claims 1 to 3, wherein the at least one thiol-functionalized organic compound comprises an α-mercaptoacetic acid ester or β-mercaptopropionic acid ester of at least one alcohol.

5. The at least one thiol-functionalized organic compound is dipentene dimercaptan; ethylcyclohexyl dimercaptan; ethylene-1,2-bis-3-mercaptoacetate; ethylene-1,2-bis-3-mercaptopropionate; 1,2,3-propanetrithiol; 1,2,6-Hexanetrithiol; Pentaerythritolthiol; Pentaerythritoltetrakis(2-mercaptoacetate); Pentaerythritoltetrakis(3-mercaptopropionate); Trimethylolpropanetris(3-mercaptopropionate); 1,1,1-Propanetriyltris(mercaptoacetate) and formula R-(R'-CH(OH)-CH 2 -SH) n A curable resin composition according to any one of claims 1 to 4, comprising at least one thiol-functionalized organic compound, wherein R' is a linear alkyl group having 3 to 30 carbon atoms, R' is a linear alkylene group having 3 to 30 carbon atoms, and n is an integer from 2 to 6.

6. The aforementioned at least one non-room temperature stable organic peroxide is a diacyl peroxide; peroxy dicarbonate; peroxy ester; di(n-propyl) peroxy dicarbonate; di(sec-butyl) peroxy dicarbonate; di(2-ethylhexyl peroxy dicarbonate); 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate; α-cumyl peroxyneodecanoate; tert-amyl peroxyneodecanoate; α-cumyl peroxyneodecanoate; tert-butyl peroxyneodecanoate The solution comprises at least one of the following: tert-amyl peroxypivalate; tert-butyl peroxypivalate; 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane; tert-amyl peroxy-2-ethylhexanoate; 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate; tert-hexyl peroxy-2-ethylhexanoate; tert-butyl peroxy-2-ethylhexanoate; dilauryl peroxide solution; or dibenzoyl peroxide solution. Preferably, the curable resin composition according to any one of claims 2 to 5 comprises at least one of tert-amylperoxy-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; tert-hexylperoxy-2-ethylhexanoate; or 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate.

7. The curable resin composition according to any one of claims 2 to 6, wherein the at least one non-room temperature stable organic peroxide comprises at least one of the following: peroxydicarbonate; peroxyester; diacyl peroxide; tert-amylperoxy-2-ethylhexanoate, tert-butylperoxy-2-ethylhexanoate; 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate; tert-hexylperoxy-2-ethylhexanoate; dilauryl peroxide solution, or dibenzoyl peroxide solution.

8. The aforementioned at least one room-temperature stable organic peroxide is a hemiperoxyketal; peroxyester, monoperoxycarbonate; peroxyketal; 1-tert-amylperoxy-1-methoxycyclohexane; tert-butylperoxyacetate; tert-amylperoxyacetate; tert-butylperoxybenzoate; 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane; 1,1-di(tert-amylperoxy)cyclohexane; 1,1-di(1-butylperoxy)cyclohexane; 2,2-di(tert-butyl A curable resin composition according to any one of claims 1 to 7, comprising at least one of the following: peroperoxy)butane; OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amylperoxy-O-isopropyl-monoperoxycarbonate; OO-tert-butylperoxy-O-isopropylmonoperoxycarbonate; polyethertetrakis(tert-butylperoxycarbonate); or tert-amylperoxybenzoate.

9. The curable resin composition according to any one of claims 1 to 8, wherein the at least one salt of the at least one metal comprises a halide, nitrate, sulfate, carboxylate, lactate, acetate, hexanoate, or naphthenate of at least one transition metal.

10. The at least one salt of the at least one metal is at least one copper halide, zinc halide, or lithium halide, preferably ZnCl 2 and / or LiCl and / or Cu(II) chloride, most preferably ZnCl 2 A curable resin composition according to any one of claims 1 to 9, comprising the above.

11. The curable resin composition according to any one of claims 1 to 10, wherein the at least one curable resin comprises at least one of an alkyd resin, an unsaturated polyester resin, a vinyl ester resin, a (meth)acrylate resin, or a mixture or blend thereof.

12. A cured resin composition obtained by curing the curable resin composition according to any one of claims 1 to 11.

13. A composite material comprising the cured resin composition according to claim 13 and at least one reinforcing filler.

14. The composite material according to claim 13, wherein the composite material is in the form of an extruded product or a field-cured pipe.

15. An impregnated article comprising a reinforcing filler impregnated with at least one of the curable resin compositions described in any one of claims 1 to 11.

16. A method for manufacturing pultruded fiber-reinforced resin products, To obtain a resin-coated continuous fiber strand by coating a continuous fiber strand with a curable resin composition according to any one of claims 1 to 11; A stretched structure is obtained by passing the resin-coated continuous fiber strand through the molding zone; and Heating the curable resin composition to a temperature effective for initiating the curing of the curable resin composition; Methods that include...

17. A method for manufacturing in-situ hardened pipes, An impregnated liner is obtained by impregnating a liner with the curable resin composition described in any one of claims 1 to 11; Placing the impregnated liner material inside the existing piping; Heating the impregnated liner in the existing piping to a temperature effective for initiating the curing of the curable resin composition; Methods that include...

18. A method for manufacturing resin transition molded articles, A method comprising impregnating a fiber-reinforced material in a suitable mold with a curable resin composition according to any one of claims 1 to 11 to obtain a composite part.

19. A method for preparing a cured composition, a) At least one curable resin that can be cured by an organic peroxide; b) At least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; c) Optionally, at least one non-room temperature stable organic peroxide that is liquid at 10°C or below and has a half-life temperature of less than 100°C; d) At least one salt of at least one metal, including at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; e) at least one thiol-functionalized organic compound; and f) Optionally, at least one solvent comprising at least one alcohol, glycol, or glycol ether; To provide a curable resin composition by combining the following; and Heating the curable resin composition to a temperature effective for initiating the curing of the curable resin composition; Methods that include...

20. A hardening system, i) The first component includes the following: At least one room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; and At least one non-room temperature stable organic peroxide that is liquid below 10°C and has a half-life temperature of less than 100°C; Here, the first component is optionally substantially free of styrene; ii) Second component including the following: A salt of at least one metal comprising at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; At least one thiol-functionalized organic compound; and Optionally, at least one solvent comprising at least one alcohol, glycol, or glycol ether; A curing system including

21. The curing system according to claim 20, wherein the first component is substantially styrene-free, and the second component comprises at least one solvent comprising at least one of an alcohol, a glycol, or a glycol ether.

22. A curing system according to claim 20 or 21, The aforementioned at least one non-room temperature stable organic peroxide is a diacyl peroxide; peroxy dicarbonate; peroxy ester; di(n-propyl) peroxy dicarbonate; di(sec-butyl) peroxy dicarbonate; di(2-ethylhexyl peroxy dicarbonate); 3-hydroxy-1,1-dimethylbutyl peroxy neodecanoate; α-cumyl peroxy neodecanoate; tert-amyl peroxy neodecanoate; tert-butyl peroxy neodecanoate; tert-amyl peroxy pivalate; tert-butyl peroxy pivalate; 2,5-di(2-ethylhexanoyl peroxy)-2,5-dimethyl Hexane; tert-amylperoxy-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; (1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate); tert-hexylperoxy-2-ethylhexanoate; dilauryl peroxide solution; or dibenzoyl peroxide solution; preferably comprising at least one of tert-amylperoxy-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; tert-hexylperoxy-2-ethylhexanoate; or 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate; The aforementioned at least one room-temperature stable organic peroxide is hemiperoxyketal, peroxyester; monoperoxycarbonate; peroxyketal; 1-tert-amylperoxy-1-methoxycyclohexane; tert-amylperoxyacetate; tert-butylperoxyacetate; tert-butylperoxybenzoate; 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane; 1,1-di(tert-amylperoxy)cyclohexane; 1,1-di(1-butylperoxy)cyclohexane; 2,2- A curing system comprising at least one of the following: di(tert-butylperoxy)butane; OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amylperoxy-O-isopropyl-monoperoxycarbonate; OO-tert-butylperoxy-O-isopropylmonoperoxycarbonate; polyethertetrakis(tert-butylperoxycarbonate); or tert-amylperoxybenzoate.

23. The curing system according to any one of claims 20 to 22, wherein the at least one thiol-functionalized organic compound comprises at least one thiol-functionalized organic compound having two or more thiol functional groups.

24. The curing system according to any one of claims 20 to 23, wherein the at least one thiol-functionalized organic compound comprises an α-mercaptoacetic acid ester or β-mercaptopropionic acid ester of at least one alcohol.

25. The at least one thiol-functionalized organic compound is dipentene dimercaptan; ethylcyclohexyl dimercaptan; ethylene-1,2-bis-3-mercaptoacetate; ethylene-1,2-bis-3-mercaptopropionate; 1,2,3-propanetrithiol; 1,2,6-Hexanetrithiol; Pentaerythritolthiol; Pentaerythritoltetrakis(2-mercaptoacetate); Pentaerythritoltetrakis(3-mercaptopropionate); Trimethylolpropanetris(3-mercaptopropionate); 1,1,1-Propanetriyltris(mercaptoacetate) and formula R-(R'-CH(OH)-CH 2 -SH) n A curing system according to any one of claims 20 to 24, comprising at least one thiol-functionalized organic compound, wherein R' is a linear alkyl group having 3 to 30 carbon atoms, R' is a linear alkylene group having 3 to 30 carbon atoms, and n is an integer from 2 to 6.

26. The at least one thiol-functionalized organic compound comprises pentaerythritol tetrakis(3-mercaptopropionate), and the at least one salt of the at least one metal is ZnCl 2 A curing system according to any one of claims 20 to 25, comprising, wherein the solvent comprises a glycol ether.

27. A curable resin composition including the following: a) At least one curable resin comprising at least one of alkyd resins, unsaturated polyester resins, vinyl ester resins, or (meth)acrylate resins, or a mixture or blend thereof, wherein the curable resin is curable by a liquid organic peroxide; b) At least one liquid organic peroxide selected from the following group: i) A room-temperature stable organic peroxide that is liquid at 25°C and has a half-life temperature of 100°C or higher; or ii) Non-room temperature stable organic peroxides that are liquid at 10°C or below and have a half-life temperature of less than 100°C; or iii) A blend or mixture of organic peroxide (i) and organic peroxide (ii); c) At least one salt of at least one metal, including at least one of Li, Al, Mg, Co, Fe, Cu, Zn, Ni, Mn, Cr, Sn, Au, Pd, or Pt; d) at least one thiol-functionalized organic compound; and e) Optionally, at least one solvent comprising at least one of an alcohol, glycol, or glycol ether.

28. A liquid organic peroxide composition, comprising the following blend: The first organic peroxide; Second organic peroxide; At least one transition metal salt dissolved in a solvent containing at least one alcohol, glycol, or glycol ether; and At least one thiol-functionalized organic compound; Includes, The blend is a liquid organic peroxide composition that is stable at 18°C ​​or higher, preferably 20°C or higher, more preferably 23°C or higher, for at least 1 hour, preferably at least 2 to 8 hours, more preferably at least 8 to 15 hours, and most preferably at least 24 hours.

29. The liquid organic peroxide composition according to claim 28, wherein the first organic peroxide is a non-room temperature stable organic peroxide having a half-life temperature of less than 100°C over one hour.

30. The liquid organic peroxide composition according to claim 28 or 29, wherein the second organic peroxide is a room-temperature stable peroxide having a half-life temperature of 100°C or higher over one hour.

31. The non-room temperature stable organic peroxide comprises at least one of tert-amylperoxy-2-ethylhexanoate, tert-butylperoxy-2-ethylhexanoate, 2,5-di(2-ethylhexanoylperoxy)-2,5-dimethylhexane, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, tert-hexylperoxy-2-ethylhexanoate, or benzoyl peroxide, according to claim 29 or 30.

32. The room-temperature stable peroxides are hemiperoxyketal; peroxyester; monoperoxycarbonate; peroxyketal; 1-tert-amylperoxy-1-methoxycyclohexane; tert-butylperoxyacetate; tert-amylperoxyacetate; tert-butylperoxybenzoate; 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane; 1,1-di(tert-amylperoxy)cyclohexane; 1,1-di(1-butylperoxy)cyclohexane; 2,2-di(tert-butylperoxy)buta A liquid organic peroxide blend according to any one of claims 29 to 31, comprising at least one of the following: n; OO-tert-butyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amyl-O-(2-ethylhexyl)-monoperoxycarbonate; OO-tert-amylperoxy-O-isopropyl-monoperoxycarbonate; OO-tert-butylperoxy-O-isopropylmonoperoxycarbonate; polyethertetrakis(tert-butylperoxycarbonate); or tert-amylperoxybenzoate.

33. The liquid organic peroxide composition according to any one of claims 28 to 32, wherein the first peroxide comprises tert-amylperoxy-2-ethylhexanoate; tert-butylperoxy-2-ethylhexanoate; or 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate.

34. The liquid organic peroxide composition according to any one of claims 28 to 33, wherein the second peroxide comprises tert-butylperoxybenzoate; tert-amylperoxybenzoate; or tert-butylperoxyacetate.

35. The aforementioned metal halide is ZnCl 2 A liquid organic peroxide composition according to any one of claims 28 to 34, comprising:

36. The liquid organic peroxide composition according to any one of claims 28 to 35, wherein the solvent comprises diethylene glycol monobutyl ether.

37. The liquid organic peroxide composition according to any one of claims 28 to 36, wherein the thiol compound comprises pentaerythritol tetrakis(3-mercaptopropionate).

38. The first peroxide comprises tert-amylperoxy-2-ethylhexanoate or 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate; The second peroxide comprises tert-butylperoxybenzoate; The metal halide contains ZnCl 2 and; The solvent comprises diethylene glycol monobutyl ether; and The liquid organic peroxide composition according to any one of claims 28 to 32, wherein the thiol compound comprises pentaerythritol tetrakis(3-mercaptopropionate).

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