Phloroglucinol acetaldehyde resin, method of preparation, and use in rubber compositions

Abstract

The phloroglucinolic acetaldehyde resin comprises a plurality of phloroglucinolic units defined by formula (I): wherein the number of phloroglucinolic units is an integer from 2 to 20; at least one of R1, R2, and R3 is linked to a second phloroglucinolic unit to form a methyl-substituted methylene bridge; and the second and third of R1, R2, and R3 are hydrogen atoms or linked to another phloroglucinolic unit to form another methyl-substituted methylene bridge; with the proviso that for any terminal unit of formula (I), any two of R1, R2, and R3 are hydrogen atoms. [Formula 1] TIFF2024511748000013.tif33156

Description

Technical Field

[0001] The present invention relates to phloroglucinol acetaldehyde resin and a method for producing the same. Such phloroglucinol acetaldehyde resin is a liquid and is useful in fabric dipping formulations for treating fibers, filaments, fabrics or cords to enhance adhesion to rubber compounds. The production of dipping adhesive compositions containing such phloroglucinol acetaldehyde resin in solution and the production of vulcanizable rubber compositions containing textile materials coated with the resulting dipping adhesive compositions are also envisioned.

Background Art

[0002] Resorcinol-formaldehyde resins (also called RF resins or resorcinolic resins), formed as reaction products of resorcinol and formaldehyde, have been widely used in various applications including fabric dipping techniques. These dipping techniques have been widely used throughout the rubber and tire industries to enhance the adhesion of rubber reinforcing materials such as fibers, filaments, fabrics or cords of natural and synthetic rubbers to polyesters (such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN)) and polyamides (such as nylon and aramid). Fabrics are typically treated by dipping or otherwise coating the fabric with an aqueous latex suspension containing the RF resin, the composition of which is also called an RFL dip. It will be understood that the RF resin is a solid and must therefore be used in an aqueous latex suspension.

[0003] Resorcinol-based resins typically contain 10–20% unreacted or free resorcinol. However, the presence of free resorcinol can pose a risk to human and environmental health. Formaldehyde has also been used for many years to produce resorcinol-formaldehyde resins. Given its widespread use, toxicity, and volatility, formaldehyde poses potential health and environmental problems. In 2011, the US National Toxicology Program listed formaldehyde as a known human carcinogen.

[0004] Therefore, there is a need to create environmentally friendly adhesives that do not use resorcinol and formaldehyde. Unfortunately, all known prior art to date that does not contain resorcinol and formaldehyde generally requires improved adhesive performance, more practical dip preparation, and longer storage stability.

[0005] Resins for RF-free dipping are known in the art. For example, U.S. Patent Application Publication US2015 / 0315410 describes an aqueous adhesive composition comprising an acrylic resin, an epoxy resin, a blocked polyisocyanate, and a styrene-butadiene-vinylpyridine latex. Note that in addition to having several different components, none of these components contain phloroglucinol.

[0006] In U.S. Patent Application Publication US2018 / 0118983, an aqueous adhesive composition comprises an aromatic polyaldehyde having at least two aldehyde functional groups and containing at least one aromatic nucleus, and a polyphenol containing at least one aromatic nucleus. Generally, phloroglucinol is disclosed in this reference (as a polyphenol), but the composition does not contain acetaldehyde and rather requires an aromatic polyaldehyde, which makes the preparation of the dipping solution inefficient compared to conventional RFL techniques due to the longer time required to complete the reaction between the polyphenol and the aromatic polyaldehyde. Furthermore, polyaldehydes are expensive materials and require particularly vigorous stirring due to their low solubility in the dipping composition.

[0007] Therefore, there is still a need for RF resin-free dipping resins that are at least as efficient as conventional RFL technology, do not require expensive materials, and can be solubilized in the dipping composition without vigorous stirring, making them suitable for use with dipping adhesive compositions. [Overview of the project] [Means for solving the problem]

[0008] At least one aspect of the present invention provides a phloroglucinol acetaldehyde resin comprising a reaction product of a phloroglucinol compound, such as phloroglucinol, and acetaldehyde. To produce the phloroglucinol acetaldehyde resin, the phloroglucinol compound is reacted with acetaldehyde in the presence of an organic solvent.

[0009] Generally, phloroglucinol acetaldehyde resins are of formula (I) [ka] The formula includes multiple phloroglucinol units defined by (wherein the formula, the number of phloroglucinol units is an integer between 2 and 20, at least one of R1, R2, and R3 is linked to a second phloroglucinol unit to form a methyl-substituted methylene bridge, the second and third of R1, R2, and R3 are either hydrogen atoms or linked to another phloroglucinol unit to form another methyl-substituted methylene bridge, provided that for any terminal unit of formula (I), any two of R1, R2, and R3 are hydrogen atoms).

[0010] Another aspect of the present invention provides a dipping adhesive composition for bonding textiles to a rubber compound, comprising a phloroglucinol acetaldehyde resin and water, wherein the phloroglucinol acetaldehyde resin is solubilized or substantially uniformly dispersed in water. In one or more embodiments, the dipping adhesive composition further comprises an unsaturated rubber latex. In one or more embodiments, the dipping adhesive composition may optionally contain any additives that further enhance or promote the adhesion of the textile to the rubber compound. Such adhesion-promoting additives may be selected from the group consisting of blocked diisocyanates, water-soluble or dispersible aliphatic epoxy compounds, or combinations thereof. The water-soluble or dispersible aliphatic epoxy compounds should have good stability in the final solution.

[0011] A further aspect of the present invention provides a coated textile comprising the above-described dipping adhesive composition. That is, the coated textile is coated with a phloroglucinol acetaldehyde resin comprising the reaction product of a phloroglucinol compound and acetaldehyde. Generally, the coated textile can be produced by dipping a textile material in the dipping adhesive composition. The textile material may be selected from films, fibers, filaments, fabrics, cords, and mixtures thereof. In one or more embodiments, the textile material is made of polyamide or polyester. In the same or other embodiments, the textile material is a fiber or cord.

[0012] A further aspect of the present invention provides a vulcanizable rubber composition comprising a vulcanizable rubber; a curing agent; and a textile material coated with a dipping adhesive composition comprising a phloroglucinol acetaldehyde resin. Advantageously, it will be understood that the vulcanizable rubber composition of the present invention exhibits advantageous rubber properties, such as adhesive properties, compared to conventional products such as RF resins. [Modes for carrying out the invention]

[0013] This invention is at least in part based on the discovery of a phloroglucinol acetaldehyde resin that can replace resorcinol-formaldehyde (RF) resins for use as a dipped adhesive composition in a variety of applications, including fiber or fabric dipping techniques. As described above, dipping techniques, typically in the form of dipping adhesive compositions, have been widely used throughout the rubber and tire industry to enhance the adhesion of rubber-reinforced materials such as fibers, films, filaments, fabrics, or cords of polyester (such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN)) and polyamides (such as nylon and aramid) to natural and synthetic rubber. Like RF resins, phloroglucinol acetaldehyde resins are described in aqueous or basic solvents, latex-based suspensions, or mixtures. The textile material fabric, fiber, or cord is then treated by dipping or otherwise coating the textile material with an aqueous latex suspension containing a phloroglucinol acetaldehyde resin, which is essentially a dipping adhesive composition. Next, a vulcanizable rubber composition can be provided by adding a vulcanizable rubber composition and a curing agent to a textile material coated with a dipping adhesive composition containing a phloroglucinol acetaldehyde resin. It will be understood that the phloroglucinol acetaldehyde resin is solid and therefore must be used in an aqueous or basic solvent latex suspension. However, importantly, the composition does not contain resorcinol or formaldehyde. Instead, a phloroglucinol acetaldehyde resin is used.

[0014] The phloroglucinol acetaldehyde resin of the present invention is of formula (I) [ka] It can be depicted as shown in (wherein the formula, the number of phloroglucinol units is an integer between 2 and 30, and at least one of R1, R2, and R3 combines with a second phloroglucinol unit to form a methyl-substituted methylene bridge, and the second and third of R1, R2, and R3 are either hydrogen atoms or combine with another phloroglucinol unit to form another methyl-substituted methylene bridge). That is, if R1, R2, or R3 in formula (I) form a methyl-substituted methylene bridge, it will be understood that a phloroglucinol unit will be bonded to the other side of each bridge. Thus, there will be a second phloroglucinol unit bonded to the other side of the methyl-substituted methylene bridge of R1, a third phloroglucinol unit bonded to the other side of the methyl-substituted methylene bridge of R2, and a fourth phloroglucinol unit bonded to the other side of the methyl-substituted methylene bridge of R3. This will continue during polymerization until acetaldehyde is consumed in the reaction mixture. If R1, R2, or R3 are not formed as methyl-substituted methylene bridges, hydrogen atoms are provided at those sites in formula (I). Furthermore, it will be understood that in any terminal unit of formula (1), any two of R1, R2, and R3 can together be hydrogen atoms. Thus, the "terminal unit" means that there is only one methyl-substituted methylene bridge at R1, R2, or R3 as shown in formula (I), and no other such bridges exist.

[0015] In some embodiments, the number of phloroglucinol units is an integer between 2 and 30, and in other embodiments, the number of phloroglucinol units is an integer between 2 and 20. In further embodiments, the number of phloroglucinol units is an integer between 2 and 15, and in even further embodiments, the number of phloroglucinol units is an integer between 2 and 10.

[0016] Some embodiments of the phloroglucinol acetaldehyde resin can also be shown and described in other ways, and therefore the phloroglucinol acetaldehyde resin of the present invention is of formula (II) [ka] It will be understood that the structure can be drawn as shown in formula (II) (wherein n is an integer from 1 to 15, and R1, both R2s, and R3 are either a methyl-substituted methylene bridge or a hydrogen atom, provided that for any terminal unit in formula (II), R1, R2, and R3 are hydrogen atoms). A methyl-substituted methylene bridge is already shown in formula (II) between the two phloroglucinol units drawn therein. If R1, either R2, or R3 in formula (II) forms such a methyl-substituted methylene bridge, it will be understood that further phloroglucinol units will bond to the other side of the bridge. However, only a maximum of 30 phloroglucinol units may extend from R1, either R2, or R3 before termination. In other embodiments, only a maximum of 20 phloroglucinol units may extend from R1, either R2, or R3 before termination. In yet another embodiment, only a maximum of 10 phloroglucinol units may extend from R1, either R2, or R3 before termination. Therefore, the chain of phloroglucinol units extending from R1, either R2, or R3 is not infinite. However, the reaction with acetaldehyde will continue during polymerization until the acetaldehyde is consumed in the reaction mixture. If R1, either R2, or R3 is not formed as a methyl-substituted methylene bridge, then hydrogen atoms are provided at those sites in formula (II). Furthermore, it will be understood that in any terminal unit of formula (II), R2 and R3 of the left-hand unit, or R1 and R2 of the right-hand unit, together become hydrogen atoms. Thus, by “terminal unit,” it is understood that for this formula, as shown in formula (II), there is only one methyl-substituted methylene bridge on the last terminal unit of phloroglucinol, and that R1 and R2 at one end and R3 and R2 at the other end become hydrogen atoms.

[0017] In some embodiments, n is an integer between 1 and 15, and in other embodiments, n is an integer between 1 and 10. In further embodiments, n is an integer between 1 and 8, and in even further embodiments, n is an integer between 1 and 5. It will be understood that n in formula (II) is independent of the number of phloroglucinol units in formula (I) and should be considered as separate formulas. Therefore, it will be understood that the number of phloroglucinol units in formula (II) may be greater than or less than the number of phloroglucinol units in formula (I).

[0018] The phloroglucinol acetaldehyde resin of the present invention can be characterized by its molecular weight. The molecular weight of the phloroglucinol acetaldehyde resin can be determined using several methodologies, and it will be understood that the molecular weight is typically reported by weight-average molecular weight (Mw) or number-average molecular weight (Mn). Useful techniques for determining the molecular weight of solid phloroglucinol acetaldehyde resin include gel permeation chromatography (GPC) or vapor phase osmosis using polystyrene standards.

[0019] In one or more embodiments, the Mw of the resin is greater than 260 g / mol, greater than 310 g / mol in other embodiments, greater than 360 g / mol in other embodiments, greater than 450 g / mol in other embodiments, greater than 550 g / mol in other embodiments, and greater than 650 g / mol in other embodiments. In these or other embodiments, the Mw of the resin is less than 1900 g / mol, less than 1800 g / mol in other embodiments, less than 1700 g / mol in other embodiments, and less than 1600 g / mol in other embodiments. In these or other embodiments, the phloroglucinol acetaldehyde resin of the present invention can be characterized by an Mw of about 260 g / mol to about 1900 g / mol, about 310 g / mol to about 1800 g / mol in other embodiments, about 450 g / mol to about 1700 g / mol in other embodiments, and about 650 g / mol to about 1600 g / mol in other embodiments.

[0020] More specifically, and in one or more embodiments, the phloroglucinol acetaldehyde resin of the present invention is generally prepared by reacting a phloroglucinol compound with acetaldehyde in the presence of an organic solvent. And as described above, it will be understood that the phloroglucinol compound includes, but is not limited to, a trivalent phenol or 1,3,5-trihydroxybenzene, or phloroglucinol, also called free phloroglucinol. The chemical formula of phloroglucinol is depicted in the following formula (III).

Chemical formula

[0021] The molar ratio of acetaldehyde to phloroglucinol may vary from 0.1:1 to 5:1. In some other embodiments, the molar ratio may vary from greater than 0.2:1 to less than 5:1. In other embodiments, the molar ratio may vary from 0.6:1 to 4:1, and in other embodiments, the molar ratio may vary from greater than 0.6:1 to less than 3:1. In some embodiments, the molar ratio may desirably be less than 2:1 or even less than 1:1, while in other embodiments the molar ratio may desirably be greater than 0.6:1, greater than 0.7:1, greater than 0.8:1, or even greater than 1:1.

[0022] Examples of suitable organic solvents useful in the production of phloroglucinol acetaldehyde resins include polar and nonpolar solvents. During use, the solvent allows the phloroglucinol compound and acetaldehyde to react to form the phloroglucinol acetaldehyde resin. In one or more embodiments, the solvent may be selected from acetone, methyl isobutyl ketone (MIBK), methyl tert-butyl ether, cyclopentyl methyl ether, ethyl acetate, methanol, ethanol, isopropanol, n-propanol, acetonitrile, dimethyl sulfoxide, dimethylformamide and tetrahydrofuran, chlorobenzene, dichlorobenzene, pentane, hexane, toluene and xylene. In one or more embodiments, methanol or ethanol is preferably used.

[0023] In one or more embodiments, the reaction (i.e., the formation of the phloroglucinol acetaldehyde resin) can be carried out at a temperature between 10 and 150 °C, and in other embodiments, within a temperature range of about 25 to about 130 °C. In one embodiment, the reaction temperature is above 30 °C, while in another embodiment, the reaction temperature is above 45 °C. In yet another embodiment, the reaction temperature is above 60 °C, and in yet another embodiment, the reaction temperature is above 70 °C.

[0024] In one or more embodiments, the reaction of a phloroglucinol compound with acetaldehyde occurs in the presence of a threshold amount of organic solvent. Specifically, the amount of organic solvent present in the reaction can be described with reference to the amount of phloroglucinol (or other phloroglucinol compound) added to the reaction (i.e., the amount of phloroglucinol in the initial mixture). Generally, the initial mixture in which the reaction occurs contains more than 20 parts by weight of organic solvent per 100 parts by weight of phloroglucinol. In some embodiments, more than 35 parts by weight of organic solvent per 100 parts by weight of phloroglucinol is used, while in other embodiments, more than 50 parts by weight of organic solvent per 100 parts by weight of phloroglucinol can be used. Generally, the phloroglucinol (before aldehyde addition) in the organic solvent mixture in which the reaction occurs contains less than 500 parts by weight of organic solvent per 100 parts of phloroglucinol. In some embodiments, less than 400 parts by weight of organic solvent per 100 parts by weight of phloroglucinol is used, and in these and other embodiments, less than 300 parts by weight of organic solvent per 100 parts by weight of phloroglucinol is used. In one or more embodiments, the reaction mixture contains about 20 to about 500 parts by weight of an organic solvent per 100 parts by weight of phloroglucinol. In other embodiments, about 35 to about 400 parts by weight of an organic solvent per 100 parts of phloroglucinol may be used, and in other embodiments, about 50 to about 300 parts by weight of an organic solvent per 100 parts by weight of phloroglucinol may be used.

[0025] Once the reaction is complete, it will be understood that the resulting phloroglucinol acetaldehyde resin can be separated from the organic solvent by any method known in the art. In one or more embodiments, the organic solvent may be evaporated or otherwise removed, such as by vacuum distillation, leaving the resin as a residue. The resin may then be discharged from its container for use as desired. In one or more embodiments, the mixture can be separated using gas chromatography. In one or more embodiments, the solid resin can be separated from the organic solvent by filtration or decanting of the mixture.

[0026] Next, the phloroglucinol acetaldehyde resin of the present invention can be mixed with water to form an aqueous dipping adhesive composition. Such an aqueous dipping adhesive composition containing the phloroglucinol acetaldehyde resin is prepared as a single-dip or two-step dipping method for treating textiles in various applications. Typically, such a dipping formulation can be used as an aqueous dipping adhesive composition for bonding textiles to a rubber compound. The dipping adhesive composition comprises the phloroglucinol acetaldehyde resin and water, wherein the phloroglucinol acetaldehyde resin is solubilized or substantially uniformly dispersed in water.

[0027] In the single-dip method, the aqueous dip formulation is prepared by mixing a phloroglucinol acetaldehyde resin with water. If necessary, pH adjustment may be performed by adding an alkaline substance. In one or more embodiments, the alkaline substance may be selected from the group consisting of sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, and ammonium hydroxide. In certain embodiments, the alkaline substances are sodium hydroxide and ammonium hydroxide. The unsaturated rubber latex is then added to the dip formulation. The resulting dip adhesive composition is ready for immediate use or can be stored at room temperature for about 24 hours to several weeks before use.

[0028] In one or more embodiments, the unsaturated rubber latex may be selected from the group consisting of butadiene copolymer, polybutadiene, isoprene copolymer, polyisoprene, styrene-butadiene copolymer, and styrene-butadiene-vinylpyridine terpolymer. In a particular embodiment, the unsaturated rubber latex is styrene-butadiene-vinylpyridine terpolymer.

[0029] In the two-step dipping method, the textile is treated or coated with a subcoat solution containing at least one adhesive compound selected from polyepoxide compounds, blocked polyisocyanate compounds, or ethylene urea compounds as the first dipping solution. Suitable polyepoxide compounds include those containing molecules with one or more epoxy groups and made from glycerol, pentaerythritol, sorbitol, ethylene glycol, polyethylene glycol, and resorcinol. In at least one embodiment, the polyepoxide compound contains no resorcinol at all. Of these adhesive compounds, polyepoxides of polyhydric alcohols are particularly suitable. Blocked polyisocyanates are selected from lactams, phenols, and oxime-blocked isocyanates, including toluene diisocyanate, metaphenylenediisocyanate, diphenylmethane diisocyanate, triphenylmethane triisocyanate, and hexamethylene diisocyanate. This subcoat solution treatment, in the presence of water, actually activates the fiber surface and enhances its interaction with the second dipping solution, whose main component is primarily a phloroglucinol acetaldehyde resin. Therefore, in the two-step procedure, the textile material is first dipped in a subcoat solution containing an adhesive compound to activate and enhance the fiber surface for interaction with the second dipping solution. Then, the textile is dipped in the second dipping solution to give a rubber-reinforced textile material.

[0030] Rubber-reinforced textile materials, which can be used to improve adhesive performance for various industrial applications, may take the form of filament yarns, cords, and woven fabrics containing synthetic fibers such as polyamide fibers, polyester fibers, aromatic polyamide fibers, and polyvinyl alcohol fibers, and are characterized in that their surfaces are coated with an adhesive composition to enhance the interaction with the textile material, fluoroglucinol acetaldehyde resin, and rubber.

[0031] Generally, processes for bonding textile materials to rubber are well known in the art. Therefore, in a process for bonding textile materials such as polyester cord to a rubber compound, a conventional dipping apparatus is used, thereby continuously passing the cord through a dip bath containing a dipping adhesive composition prepared using a phloroglucinol acetaldehyde resin produced by a one-step method and manufactured according to embodiments of the present invention. Excess dip is removed by blowing the cord with an air jet, and the cord is dried for approximately 120 seconds in an oven set to 170°C. The cord is then cured at a temperature of approximately 230°C for a sufficient time to allow the dip to penetrate the polyester cord. A curing time of approximately 60 seconds has been found to be suitable and acceptable in most cases.

[0032] To test the success of bonding polyester cords to vulcanizable rubber, cords treated with a phloroglucinol acetaldehyde resin-based adhesive are embedded in a compounded uncured rubber compound and then vulcanized. The rubber compound is vulcanized for approximately 15–18 minutes at 160°C, for a time and temperature sufficient to promote good adhesion. For specific tests, the standard H adhesion test method in accordance with ASTM D-4776 was used to determine the static adhesion of the textile tire cords to the rubber.

[0033] Considering this test, it was found that textiles treated with the generated phloroglucinol acetaldehyde resin-based adhesive are useful in vulcanizable rubber compositions. Apart from the use of the phloroglucinol acetaldehyde resin of the present invention, the vulcanizable composition may be substantially conventional. Therefore, the rubber composition may include vulcanizable rubber, a curing agent, a filler, and a textile material coated with a dipping adhesive composition containing the phloroglucinol acetaldehyde resin of the present invention. Advantageously, it will be understood that the vulcanizable rubber composition of the present invention exhibits advantageous rubber properties, such as adhesive properties, compared to conventional products such as RF resins.

[0034] With respect to the rubber composition of the present invention, the rubber composition may contain rubber components that may include any natural rubber, synthetic rubber, or a combination thereof. Examples of synthetic rubbers include, but are not limited to, styrene-butadiene copolymer, polyisoprene, polybutadiene, acrylonitrile-butadiene-styrene copolymer, polychloroprene, polyisobutylene, ethylene-propylene copolymer, and ethylene-propylene-diene rubber.

[0035] The rubber composition may contain one or more of the common additives used in such compositions. Examples of such additives include carbon black, cobalt salts, stearic acid, silica, silicic acid, sulfur, peroxides, zinc oxide, fillers, antioxidants, and softening oils.

[0036] Rubber compositions are prepared and used in conventional ways. For example, a composition can be prepared by solid-state mixing.

[0037] In consideration of the foregoing, it will be understood that rubber compositions produced according to the present invention may be used for a variety of rubber applications or rubber articles. Polyester fibers, yarns, filaments, cords, or fabrics coated with the adhesive formulations of the present invention may be used in tire applications, or to prepare radial, bias, or belted bias passenger tires, truck tires, motorcycle or bicycle tires, off-road tires, aircraft tires, transmission belts, V-belts, conveyor belts, hoses, and gasket parts. Other applications include rubber products useful for engine mounts and bushings. Other applications in which the uncured and cured rubber compositions of the present invention may be used or prepared include technical or mechanical rubber articles such as hoses, pneumatic belts, and conveyor belts. example

[0038] To illustrate the implementation of the present invention, the following examples were prepared and tested. However, these examples should not be considered to limit the scope of the invention. The claims are helpful in defining the invention. The following abbreviation PG stands for "phloroglucinol acetaldehyde". PG resins Examples 1-9 were prepared using a one-step dip method, and for Examples 7 and 9, an alkaline additive was further prepared to adjust the pH. PG resin example 1.

[0039] 50.0g phloroglucinol, acetaldehyde 50 weight 22.1 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 2.

[0040] 50.0g phloroglucinol, acetaldehyde 50 weight24.5 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 3.

[0041] 50.0g phloroglucinol, acetaldehyde 50 weight 26.9 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 4.

[0042] 50.0g phloroglucinol, acetaldehyde 50 weight 30.1 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 5.

[0043] 50.0g phloroglucinol, acetaldehyde 50 weight 34.1 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 6.

[0044] 50.0g phloroglucinol, acetaldehyde 50 weight 39.4 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 7.

[0045] 50.0g phloroglucinol, acetaldehyde 50 weight 26.9 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation. Next, 200.0 g of distilled water and 14.0 g of sodium hydroxide were added, and the solvent was removed by distillation to obtain 130.0 g of aqueous solution. The solid content was 49.2%. PG resin example 8.

[0046] 50.0g phloroglucinol, acetaldehyde 50 weight 19.2 g of a % ethyl alcohol solution and 150.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation, and the resin was discharged from the flask. PG resin example 9.

[0047] 250.0g phloroglucinol, acetaldehyde 50 weight 157.3 g of a % ethyl alcohol solution and 750.0 g of ethyl alcohol were placed in a flask and heated to 78°C. The reaction mixture was maintained at approximately 78°C for 2 hours. The solvent was then removed by vacuum distillation. Next, 800.0 g of distilled water and 70.0 g of sodium hydroxide were added, and the solvent was removed by distillation to obtain 815.0 g of aqueous solution. The solid content was 39.8%.

[0048] Table 1 below describes the various physical properties and chemical analyses of the phloroglucinol-based acetaldehyde resin. It should be noted that the molecular weight and oligomer distribution were determined by GPC analysis in the evaluation of the resin properties. The reaction products of phloroglucinol and acetaldehyde were analyzed by proton NMR spectroscopy. The molar ratio was acetaldehyde (A) to phloroglucinol (Phg) for the synthesis of the phloroglucinol-based acetaldehyde resin.

[0049] [Table 1]

[0050] In the comparison among the fluoroglucinol-containing acetaldehyde resins of the present invention, 0.6 : These phloroglucinol-based acetaldehyde resins (Examples 1-7 and 9) having a molar ratio of acetaldehyde (A:Phg) to 1 or more phloroglucinols are 0.6 : It will be understood that this yielded higher percentages of tetramers and pentamers than phloroglucinol acetaldehyde resins with a molar ratio of less than 1 A:Phg (Example 8), and furthermore, had more ethylidene crosslinks while having fewer aromatic hydrogens. As shown in Table 4, this is because 0.6 : This may have affected the stability of the dipping solution for resins with a molar ratio of less than 1.

[0051] To fully analyze the improvements brought about by the independently prepared solid phloroglucinol acetaldehyde resin described above, it is understood that a resorcinol formaldehyde resin, available from Sumitomo Chemical under the trade name PENACOLITE® RESIN R-2170, was prepared as a comparative RF resin. Subsequently, all of the above examples, including the comparative RF resin, were used in the preparation of dipping adhesive compositions.

[0052] The tire cord was dipped in a dipping adhesive composition prepared using a two-step dipping method. The complete adhesive formulation solution is shown in Table 2. The first step is the sub-coating in the first bath (identified as the sub-coat solution in Table 2), based on caprolactam-blocked methylene-bis-(4-phenylisocyanate) emulsion available from EMS-Griltech under the trade name GRILLBOND IL-6 and glycerol polyglycidyl ether available from Nagase ChemteX Corporation under the trade name DENACOL EX313. The second step is the top coating in the second bath shown in Table 2 (identified as the resin solution in Table 2). In preparation, phloroglucinol acetaldehyde resin, distilled water, and 50% sodium hydroxide were first mixed, and then 41% 2-vinylpyridine-styrene-butadiene rubber (SBR) latex was added while mixing well. Ammonium hydroxide was added to obtain the final mixed solution. The final solutions of Examples 1-7 were found to be stable at room temperature for one week. However, the final solution of Example 8 was found to be unstable at room temperature, with suspended matter present in the solution after 24 hours. The results of the final solution stability are shown in Table 4.

[0053] [Table 2]

[0054] The tire cords used in the preparation of the example were made from two 1500 denier polyethylene terephthalate (PET) yarns. Each tire cord (also called 1500 / 2 cord) was used in the adhesion performance evaluation as performed below. This cord was non-adhesive activated (NAA) PET. These cords were dipped in the subcoat dipping solution prepared as described above (i.e., the subcoat solution in Table 2). After dipping, the dipped cords were dried under tension for 120 seconds in a first oven set to 210°C. They were then dipped in the solution prepared as described above (i.e., the resin solution in Table 2) and dried under tension for 120 seconds in a second oven set to 135°C. The resulting dipped cords were then cured for 120 seconds in a third oven set to 240°C. Finally, polyethylene terephthalate cords treated with a PG resin-based adhesive dipping solution were embedded in compounded uncured rubber, cured at 160°C for 16 minutes, and the resulting samples were tested in an H tensile adhesion test performed according to ASTM method D-4776.

[0055] Therefore, dipped cord test specimens containing the phloroglucinol acetaldehyde resins described in Examples 1-8 and Examples 1-8 in Table 1, as well as the comparative RF resin, were prepared according to the rubber compositions shown in Table 3.

[0056] [Table 3]

[0057] Next, dipped cord test pieces containing each of the eight phloroglucinol acetaldehyde resins listed in Table 1 were tested against dipped cord test pieces containing a comparative RF resin (Comparative Example 1).

[0058] The stability of the dipping solution and the H-tensile adhesion test results are shown in Table 4 below. Humidity aging adhesion and heat aging adhesion were also tested.

[0059] [Table 4]

[0060] In a comparison between the phloroglucinol-based acetaldehyde resin of the present invention and conventional resorcinol-formaldehyde (RF) resins, it will be found that the phloroglucinol-based acetaldehyde resin of the present invention exhibits better pre-aging adhesion properties compared to conventional resorcinol-formaldehyde resins, while humidity-based pre-aging adhesion properties and heat-based aging adhesion properties remain relatively consistent.

[0061] The following provides a second dipping example. The code was dipped in a dipping adhesive composition prepared using a two-step dipping method. The complete adhesive formulation solution is shown in Table 5. The first step is the sub-coating in the first bath (identified as the sub-coat solution in Table 5), based on bis(2-ethylhexyl) sulfosuccinate sodium salt, available from Fisher Scientific under the trade name Aerosol® OT, and glycerol polyglycidyl ether, available from Nagase ChemteX Corporation under the trade name DENACOL EX313. The second step is the top coating in the second bath shown in Table 5 (identified as the resin solution in Table 5). In preparation, phloroglucinol acetaldehyde resin, distilled water, and 29.5% ammonium hydroxide were first mixed, and then 41% 2-vinylpyridine-styrene-butadiene rubber (SBR) latex was added while mixing well. The final solution of Example 9 was found to be stable at room temperature for one week.

[0062] [Table 5]

[0063] The cord type used in the preparation of the second example was prepared from two 1680 denier aramid yarns. Each tire cord (also called 1680 / 2 cord) was used in the adhesion performance evaluation as performed below. This cord was non-adhesive activated (NAA) aramid. These cords were dipped in the subcoat dipping solution prepared as described above (i.e., the subcoat solution in Table 5). After dipping, the dipped cords were then dried under tension for 120 seconds in a first oven set to 240°C. They were then dipped in the topcoat dipping solution prepared as described above (i.e., the resin solution in Table 5) and then dried under tension for 120 seconds in a second oven set to 145°C. The resulting dipped cords were then cured for 120 seconds in a third oven set to 240°C. Finally, the aramid cords treated with a PG resin-based adhesive dipping solution were embedded in the compounded uncured rubber, cured at 160°C for 16 minutes, and the resulting samples were tested in an H tensile adhesion test conducted according to ASTM method D-4776.

[0064] Therefore, dipped cord test specimens containing the phloroglucinol acetaldehyde resin described in Example 9 and the comparative RF resin were prepared according to the rubber compositions shown in Table 3.

[0065] Next, the dipped cord test specimens containing the phloroglucinol acetaldehyde resin described in Example 9 were tested in comparison with the dipped cord test specimens containing the comparative RF resin (Comparative Example 2).

[0066] The stability of the dipping solution and the H-tensile adhesion test are shown in Table 6 below. Humidity aging adhesion and heat aging adhesion were also tested.

[0067] [Table 6]

[0068] In a comparison between the phloroglucinol-based acetaldehyde resin of the present invention and conventional resorcinol-formaldehyde (RF) resins, it will be found that the phloroglucinol-based acetaldehyde resin of the present invention exhibits better pre-aging adhesion properties compared to conventional resorcinol-formaldehyde resins, while humidity-based pre-aging adhesion properties and heat-based aging adhesion properties remain relatively consistent.

[0069] Various modifications and alterations that do not depart from the scope and spirit of the present invention will be apparent to those skilled in the art. The present invention should not be justly limited to the exemplary embodiments described herein.

Claims

1. Equation (I) 【Chemistry 1】 It consists of multiple phloroglucinol units defined by (wherein the formula, the number of phloroglucinol units is an integer from 2 to 20, at least one of R1, R2, and R3 is linked to a second phloroglucinol unit to form a methyl-substituted methylene bridge, the second and third of R1, R2, and R3 are hydrogen atoms or linked to another phloroglucinol unit to form another methyl-substituted methylene bridge, provided that for any terminal unit of formula (I), two of R1, R2, and R3 are hydrogen atoms), According to GPC using polystyrene standards, the oligomer content of pentamers or more is less than 85%. Phloroglucinol-based acetaldehyde resin.

2. The phloroglucinol-containing acetaldehyde resin according to claim 1, comprising less than 20% by weight of unreacted phloroglucinol.

3. A phloroglucinol acetaldehyde resin according to claim 1 or 2, having an Mw greater than 650 g / mol and less than 1600 g / mol.

4. A phloroglucinol-based acetaldehyde resin according to any one of claims 1 to 3, wherein the molar ratio of acetaldehyde to phloroglucinol is 0.6:1 to 4:

1.

5. A dipping adhesive composition comprising a phloroglucinol acetaldehyde resin according to any one of claims 1 to 4.

6. The dipping adhesive composition according to claim 5, comprising unsaturated rubber latex.

7. The dipping adhesive composition according to claim 6, comprising a basic solvent.

8. A dipping adhesive composition according to any one of claims 6 to 7, wherein the pH is greater than 6 and less than 13.

9. The dipping adhesive composition according to any one of claims 6 to 8, wherein the unsaturated rubber latex is a diene elastomer selected from the group consisting of butadiene copolymer, polybutadiene, isoprene copolymer, polyisoprene, styrene-butadiene copolymer, styrene-butadiene-vinylpyridine terpolymer and mixtures thereof.

10. The dipping adhesive composition according to any one of claims 5 to 9, wherein the content of phloroglucinol acetaldehyde resin is greater than 0.1% and less than 10% by solid weight, where the amount in weight percent is the amount relative to the total weight of the dipping adhesive composition.

11. A coated textile comprising a dipping adhesive composition and a textile material according to any one of claims 5 to 10.

12. The coated textile according to claim 11, wherein the textile material is selected from films, fibers, filaments, fabrics and cords and mixtures thereof.

13. The coated textile according to claim 11 or 12, wherein the textile material is polyamide and polyester.

14. A method for coating a textile material with the dipping adhesive composition described in Claim 11, comprising the step of heat-treating the dipped textile material at a temperature of 100 to 240°C.

15. The method according to claim 14, wherein the textile material is selected from films, fibers, filaments, fabrics and cords and mixtures thereof.

16. The method according to claim 14 or 15, wherein the textile material is polyamide and polyester.

17. a. Vulcanizable rubber; b. Hardener; and c. A coated textile comprising the dipping adhesive composition according to any one of claims 11 to 13. A vulcanizable rubber composition containing the following:

18. A vulcanizable rubber prepared from the vulcanizable composition described in claim 17.

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