A kind of active group-rich water-soluble resin film-forming agent for glass fiber and preparation method thereof

Abstract

The present invention provides a water-soluble resin film-forming agent for glass fiber, which comprises 15 to 55 parts by weight of acrylic acid, 1 to 20 parts by weight of unsaturated carboxylic acid containing double bonds and / or unsaturated anhydride containing double bonds, 1 to 10 parts by weight of cohesive monomers, 1 to 10 parts by weight of adhesive monomers, 1 to 10 parts by weight of functional monomers, and 40 to 80 parts by weight of solvents, according to the mass fraction of raw materials. The film-forming agent is used as a film-forming agent in a glass fiber sizing agent, and is particularly suitable for a glass fiber film-forming agent for reinforcing nylon resin, provides good protection for glass fiber in the glass fiber preparation process, and the rich active groups can react and combine with the relevant active groups in the sizing agent and the matrix resin, and the prepared glass fiber has good interface strength with various matrix resins, and the glass fiber composite has good mechanical properties, water resistance, UV aging resistance, and thermal oxidation resistance.

Description

Technical Field

[0001] The present invention belongs to the technical field of film-forming agents for glass fibers, and relates to a water-soluble resin film-forming agent for glass fibers, a preparation method and application thereof, and a wetting agent for glass fibers, and in particular to a water-soluble resin film-forming agent rich in active groups for glass fibers, a preparation method and application thereof, and a wetting agent for glass fibers. Background Art

[0002] In the field of glass fiber manufacturing technology, sizing is extremely important for the production and application of glass fiber. First, in the process of glass fiber drawing, the sizing plays a role of lubrication, bonding and protection, avoiding severe wear of glass fiber, resulting in broken wires and flying wires, which makes the drawing operation impossible; secondly, the sizing gives glass fiber products various processing technologies and glass fiber reinforced materials the necessary technical properties, such as mechanical properties, penetration, permeability, stiffness, cutting, dispersibility, antistatic properties, ribbon formation, fluidity, etc. Therefore, the technical level of sizing is one of the prerequisites for the development of glass fiber industry and glass fiber reinforced composite materials industry, and the film-forming agent is used in the largest amount in the sizing formula, often plays a decisive role in the performance of the sizing, and is the most critical component in the sizing.

[0003] Nylon is the common name for polyamide, referred to as PA, which is a general term for resinous substances with repeating amide groups, including aliphatic, aliphatic-aromatic and aromatic polyamides, mainly made of dibasic acid and diamine, or amino acid by polycondensation. Nylon resin has high tensile strength and good impact toughness, and has a wide temperature range of use. Glass fiber reinforced PA composite materials are often used in industry, which have the characteristics of low density, low price and recyclability. At the same time, the modified composite materials have the advantages of higher mechanical properties, hardness, load deformation temperature and better dimensional stability. The glass fiber reinforced nylon resin used is generally of two types: long glass fiber reinforced and short glass fiber reinforced.

[0004] However, the hydrolysis resistance, aging resistance, and thermal oxidation resistance of glass fiber reinforced PA composite materials need to be further improved, and the service life of the composite materials is relatively low. This also limits the application of glass fiber reinforced PA composite materials in high temperature and high humidity, sunshine and rain conditions, such as automotive parts, radiator tanks, engine hoods, intake pipes, high-speed rail track buckles, insulating gauge blocks, etc.

[0005] Therefore, starting from solving the technical problems of glass fiber processing performance and enhanced PA composite material performance, how to develop a special film-forming agent for glass fiber sizing for reinforced PA, solve the above-mentioned problems existing in existing glass fiber reinforced PA composite materials, and further improve the performance and service life of the composite materials, thereby broadening the application depth and width of glass fiber reinforced PA composite materials, is of great significance and is also one of the issues widely concerned by many front-line researchers in the industry. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a water-soluble resin film-forming agent for glass fiber and its preparation method, application, a sizing agent for glass fiber, and in particular, a water-soluble resin film-forming agent rich in active groups for glass fiber. The water-soluble resin film-forming agent provided by the present invention can, on the one hand, provide the processing properties such as bundling and low hairiness required for glass fiber, and on the other hand, give glass fiber good compatibility with nylon resin. The key to the film-forming agent of the present invention is that it has abundant active groups, strong polarity and reactivity, which is conducive to providing a reaction bridge for the coupling agent and the film-forming agent, thereby greatly improving the performance of the composite material, and the prepared glass fiber reinforced PA composite material has excellent performance.

[0007] The present invention provides a water-soluble resin film-forming agent for glass fiber, which comprises, by weight of raw materials:

[0008]

[0009] Alkaline neutralizer.

[0010] Preferably, the double bond-containing unsaturated carboxylic acid includes one or more of methacrylic acid, itaconic acid and maleic acid;

[0011] The double bond-containing unsaturated anhydride includes maleic anhydride;

[0012] The cohesive monomer includes one or more of vinyl acetate, methyl acrylate and methyl methacrylate;

[0013] The adhesive monomer includes one or more of butyl acrylate, 2-ethylhexyl acrylate and isooctyl acrylate;

[0014] The weight average molecular weight of the water-soluble resin film-forming agent is 1,000 to 200,000.

[0015] Preferably, the functional monomer includes one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, glycidyl methacrylate, N-hydroxymethyl acrylamide, sodium vinyl sulfonate and sodium styrene sulfonate;

[0016] The alkaline neutralizing agent includes one or more of sodium hydroxide, ammonia water and organic amine compounds;

[0017] The organic amine compound includes one or more of diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, ethanolamine, diethanolamine and triethanolamine;

[0018] The alkaline neutralizer is used in an amount to control the pH value of the system to be 2 to 7.5.

[0019] Preferably, the solvent comprises one or more of water, methanol, ethanol, propanol, isopropanol, butanol and isobutanol;

[0020] The water-soluble resin film-forming agent is a water-soluble resin film-forming agent rich in active groups;

[0021] The raw materials also include an initiator;

[0022] The water-soluble resin film-forming agent is prepared from raw materials by solution polymerization process under nitrogen protection, heating and stirring conditions;

[0023] The solution polymerization process includes an alkali neutralization process before polymerization or an alkali neutralization process after polymerization.

[0024] The present invention provides a method for preparing a water-soluble resin film-forming agent for glass fiber as described in any one of the above technical solutions, wherein the preparation method comprises an alkali neutralization process before polymerization or an alkali neutralization process after polymerization;

[0025] The pre-polymerization alkali neutralization process comprises the following steps:

[0026] 1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer, and then adding an alkaline neutralizing agent for miscibility to obtain a miscible solution;

[0027] 2) under the action of protective gas and at the reaction temperature, adding the initiator aqueous solution and the miscible solution into the solvent for reaction, and then keeping the temperature to react to obtain a water-soluble resin film-forming agent;

[0028] The post-polymerization alkali neutralization process comprises the following steps:

[0029] (1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer to obtain a miscible solution;

[0030] (2) adding the initiator aqueous solution and the miscible solution to the solvent under the action of a protective gas at a reaction temperature, reacting the mixture, and then keeping the temperature to react to obtain an intermediate system;

[0031] (3) Adding an alkaline neutralizing agent to the intermediate system obtained in the above step for neutralization to obtain a water-soluble resin film-forming agent.

[0032] Preferably, the specific methods of adding the alkaline neutralizer in step (1) and step (3) are independently selected from: slowly adding the alkaline neutralizer while stirring until it is completely dissolved;

[0033] The miscibility temperature in step 1) is less than or equal to 40° C.

[0034] In the initiator aqueous solution, the mass ratio of water to initiator is (10-100):1;

[0035] The initiator aqueous solution and the miscible solution are added to the solvent in a manner including dropwise addition;

[0036] The dropping time is 1 to 6 hours.

[0037] Preferably, the reaction temperature is 65-95°C;

[0038] The temperature of the insulation reaction is 85-95°C;

[0039] The insulation reaction time is 0.5 to 2 hours;

[0040] The temperature of the intermediate system is less than or equal to 60°C;

[0041] The pH value of the neutralization is controlled at 2 to 7.5.

[0042] Preferably, the initiator comprises a thermal initiation system initiator or a redox system initiator;

[0043] The percentage of the thermal initiation system initiator to the monomer mass is 0.05% to 5%;

[0044] The thermal initiation system initiator includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile and azobisisoheptylnitrile;

[0045] The redox system initiator accounts for 0.05% to 5% of the monomer mass;

[0046] The redox system initiator comprises an oxidant and a reductant;

[0047] The molar ratio of the oxidant to the reductant is 1:(0.5-1);

[0048] The oxidant includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide and tert-butyl hydroperoxide;

[0049] The reducing agent includes one or more of sodium sulfite, sodium bisulfite, sodium pyrosulfite and sodium formaldehyde sulfoxylate;

[0050] The monomers include acrylic acid, unsaturated carboxylic acid containing double bonds and / or unsaturated acid anhydride containing double bonds, cohesive monomers, adhesive monomers and functional monomers.

[0051] The present invention provides use of the water-soluble resin film-forming agent described in any one of the above technical solutions or the water-soluble resin film-forming agent prepared by the preparation method described in any one of the above technical solutions in glass fiber processing.

[0052] The present invention also provides a sizing agent for glass fiber, the sizing agent comprising a film-forming agent, a coupling agent, a second film-forming agent, a cross-linking agent and a lubricant;

[0053] The film-forming agent includes the water-soluble resin film-forming agent described in any one of the above technical solutions or the water-soluble resin film-forming agent prepared by the preparation method described in any one of the above technical solutions.

[0054] The present invention provides a water-soluble resin film-forming agent for glass fiber, which comprises 15 to 55 parts by weight of acrylic acid, 1 to 20 parts by weight of unsaturated carboxylic acid containing double bonds and / or unsaturated anhydride containing double bonds, 1 to 10 parts by weight of cohesive monomers, 1 to 10 parts by weight of adhesive monomers, 1 to 10 parts by weight of functional monomers and 40 to 80 parts by weight of solvents, based on the weight of raw materials. Compared with the prior art, the present invention uses carboxylic acid monomers containing unsaturated double bonds as main monomers and prepares the film-forming agent through a solution polymerization process. On the one hand, this type of high molecular polymer forms a uniform film after drying and losing water, and can fully meet the processing performance requirements of glass fiber for film-forming agents after molecular weight control through the synthesis process and adding modified monomers for copolymerization; on the other hand, unsaturated double-bond carboxylic acid monomers can provide a large number of highly polar and reactive active groups for the film-forming agent, which is beneficial to provide a reaction bridge for the coupling agent and the film-forming agent, thereby greatly improving the performance of the composite material; on the other hand, the polymer film-forming agent is endowed with certain hydrophilic functional groups, and after reacting with an alkaline neutralizer, an ionic hydrophilic structure can be formed in water, ultimately giving the film-forming agent good water solubility, which is beneficial to the uniform coating of the film-forming agent on the surface of the glass fiber and is environmentally friendly.

[0055] The water-soluble resin film-forming agent rich in active groups for glass fiber provided by the present invention can provide processing properties such as the required bundling and low hairiness of glass fiber on the one hand, and give glass fiber good compatibility with nylon resin on the other hand. The key to the film-forming agent of the present invention is that it has abundant active groups, strong polarity and reactivity, which is conducive to providing a bridge for the reaction of coupling agents and film-forming agents, thereby greatly improving the performance of composite materials, and the prepared glass fiber reinforced PA composite material has excellent performance. The present invention is particularly suitable for the main (or secondary) film-forming agent for glass fiber for reinforcing nylon resin. It can be used as a special sizing agent for coating glass fiber to improve the surface properties of glass fiber when used in combination with other components in the sizing agent. As a film-forming agent in the glass fiber sizing agent, it is particularly suitable for the glass fiber film-forming agent for reinforcing nylon resin, providing good protection for glass fiber in the glass fiber preparation process, and the abundant active groups can react and combine with the relevant active groups in the sizing agent and the matrix resin. The prepared glass fiber has good interface strength with various matrix resins, and the glass fiber composite has good mechanical properties, water resistance, UV aging resistance, and thermal oxidation resistance.

[0056] The experimental results show that the active group-rich water-soluble resin film-forming agent provided by the present invention is used in combination with other sizing agent components such as coupling agents, second film-forming agents, cross-linking agents, lubricants, etc., and the drawing operation is stable in the glass fiber manufacturing process, the glass fiber coating effect is good, the glass fiber production is smooth, and it has the advantages of good short-cutting property, fluidity, and less hairiness. Moreover, the prepared glass fiber has good compatibility and interface strength with the composite matrix resin, and the prepared composite material has excellent mechanical properties. The tensile strength, bending strength, and impact strength of the spline are significantly improved compared with conventional sizing agent formulas, and the boiling resistance, UV resistance, and thermal oxidation resistance are improved. DETAILED DESCRIPTION

[0057] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the invention.

[0058] All raw materials of the present invention have no particular limitation on their sources, and can be purchased from the market or prepared according to conventional methods known to those skilled in the art.

[0059] There is no particular restriction on the purity of all raw materials in the present invention. The present invention preferably uses analytically pure materials or materials with conventional purity requirements in the field of glass fiber film-forming agent preparation.

[0060] The brands and abbreviations of all raw materials of the present invention are conventional brands and abbreviations in the art. Each brand and abbreviation is clear and definite in the field of its related use. Those skilled in the art can purchase them from the market or prepare them by conventional methods according to the brands, abbreviations and corresponding uses.

[0061] The present invention provides a water-soluble resin film-forming agent for glass fiber, which comprises, by weight of raw materials:

[0062]

[0063] Alkaline neutralizer.

[0064] In the present invention, the amount of acrylic acid added is 15 to 55 parts by weight, may be 20 to 50 parts by weight, preferably 25 to 45 parts by weight, and more preferably 30 to 40 parts by weight.

[0065] In the present invention, the amount of the unsaturated carboxylic acid containing a double bond and / or the unsaturated acid anhydride containing a double bond is 1 to 20 parts by weight, can be 5 to 16 parts by weight, and is preferably 9 to 12 parts by weight.

[0066] In the present invention, the amount of the cohesive monomer added is 1 to 10 parts by weight, can be 3 to 8 parts by weight, and is preferably 5 to 6 parts by weight.

[0067] In the present invention, the added amount of the adhesive monomer is 1 to 10 parts by weight, can be 3 to 8 parts by weight, and preferably 5 to 6 parts by weight.

[0068] In the present invention, the added amount of the functional monomer is 1 to 10 parts by weight, can be 3 to 8 parts by weight, and preferably 5 to 6 parts by weight.

[0069] In the present invention, the amount of the solvent added is 40 to 80 parts by weight, may be 45 to 75 parts by weight, preferably 50 to 70 parts by weight, and more preferably 55 to 65 parts by weight.

[0070] In the present invention, the double bond-containing unsaturated carboxylic acid preferably includes one or more of methacrylic acid, itaconic acid and maleic acid, and more preferably methacrylic acid, itaconic acid or maleic acid.

[0071] In the present invention, the double bond-containing unsaturated acid anhydride preferably includes maleic anhydride.

[0072] In the present invention, the cohesive monomer preferably includes one or more of vinyl acetate, methyl acrylate and methyl methacrylate, and more preferably vinyl acetate, methyl acrylate or methyl methacrylate.

[0073] In the present invention, the adhesive monomer preferably includes one or more of butyl acrylate, 2-ethylhexyl acrylate and isooctyl acrylate, and more preferably butyl acrylate, 2-ethylhexyl acrylate or isooctyl acrylate.

[0074] In the present invention, the weight average molecular weight of the water-soluble resin film-forming agent is preferably 1,000 to 200,000, more preferably 5,000 to 160,000, and even more preferably 9,000 to 120,000.

[0075] In the present invention, the functional monomer preferably includes one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, glycidyl methacrylate, N-hydroxymethyl acrylamide, sodium vinyl sulfonate and sodium styrene sulfonate, and more preferably includes hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, glycidyl methacrylate, N-hydroxymethyl acrylamide, sodium vinyl sulfonate or sodium styrene sulfonate.

[0076] In the present invention, the alkaline neutralizing agent preferably includes one or more of sodium hydroxide, ammonia water and organic amine compounds, and more preferably sodium hydroxide, ammonia water or organic amine compounds.

[0077] In the present invention, the organic amine compound preferably includes aliphatic amine compounds and / or alcohol amine compounds, more preferably aliphatic amine compounds or alcohol amine compounds. The organic amine compound preferably includes one or more of diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, ethanolamine, diethanolamine and triethanolamine, more preferably diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, ethanolamine, diethanolamine or triethanolamine. Specifically, the aliphatic amine compound preferably includes one or more of diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine and sec-butylamine. The alcohol amine compound preferably includes one or more of ethanolamine, diethanolamine and triethanolamine)

[0078] In the present invention, the amount of the alkaline neutralizer used is to control the pH value of the system to preferably be 2 to 7.5, more preferably 3 to 6.5, and more preferably 3.5 to 5.5.

[0079] In the present invention, the solvent preferably includes one or more of water, methanol, ethanol, propanol, isopropanol, butanol and isobutanol, more preferably water, methanol, ethanol, propanol, isopropanol, butanol or isobutanol.

[0080] In the present invention, the water-soluble resin film-forming agent is preferably a water-soluble resin film-forming agent rich in active groups.

[0081] In the present invention, the raw materials preferably further include an initiator.

[0082] In the present invention, the water-soluble resin film-forming agent is preferably prepared from raw materials by solution polymerization process under nitrogen protection, heating and stirring conditions.

[0083] In the present invention, the solution polymerization process preferably includes a pre-polymerization alkali neutralization process or a post-polymerization alkali neutralization process.

[0084] The present invention provides a method for preparing a water-soluble resin film-forming agent for glass fiber as described in any one of the above technical solutions, wherein the preparation method comprises an alkali neutralization process before polymerization or an alkali neutralization process after polymerization;

[0085] The pre-polymerization alkali neutralization process comprises the following steps:

[0086] 1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer, and then adding an alkaline neutralizing agent for miscibility to obtain a miscible solution;

[0087] 2) under the action of protective gas and at the reaction temperature, adding the initiator aqueous solution and the miscible solution into the solvent for reaction, and then keeping the temperature to react to obtain a water-soluble resin film-forming agent;

[0088] The post-polymerization alkali neutralization process comprises the following steps:

[0089] (1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer to obtain a miscible solution;

[0090] (2) adding the initiator aqueous solution and the miscible solution to the solvent under the action of a protective gas at a reaction temperature, reacting the mixture, and then keeping the temperature to react to obtain an intermediate system;

[0091] (3) Adding an alkaline neutralizing agent to the intermediate system obtained in the above step for neutralization to obtain a water-soluble resin film-forming agent.

[0092] In the present invention, the alkali neutralization process before polymerization comprises the following steps:

[0093] 1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer, and then adding an alkaline neutralizing agent for miscibility to obtain a miscible solution;

[0094] 2) Under the action of protective gas and at the reaction temperature, the initiator aqueous solution and the mixed solution are added to the solvent for reaction, and then the reaction is kept warm to obtain a water-soluble resin film-forming agent.

[0095] The invention firstly mixes acrylic acid, unsaturated carboxylic acid containing double bonds and / or unsaturated anhydride containing double bonds, cohesive monomer, viscous monomer and functional monomer, and then adds alkaline neutralizing agent for miscibility to obtain a miscible solution.

[0096] In the present invention, the specific manners of adding the alkaline neutralizing agent in step (1) and step (3) are each independently preferably selected from slowly adding the alkaline neutralizing agent while stirring until the alkaline neutralizing agent is completely dissolved.

[0097] In the present invention, the miscibility temperature in step 1) is preferably less than or equal to 40°C, more preferably less than or equal to 35°C, and more preferably less than or equal to 30°C.

[0098] In the present invention, the above-mentioned alkali neutralization process before polymerization, although it is a alkali neutralization process before polymerization, is to control the pH value of the product after the reaction is completed.

[0099] The invention further adds the initiator aqueous solution and the mixed solution into the solvent for reaction under the action of protective gas and at the reaction temperature, and then heat-insulates the reaction to obtain the water-soluble resin film-forming agent.

[0100] In the present invention, in the aqueous initiator solution, the mass ratio of water to initiator is preferably (10-100):1, more preferably (30-80):1, and more preferably (50-60):1.

[0101] In the present invention, the method of adding the initiator aqueous solution and the miscible solution into the solvent preferably comprises dropwise addition.

[0102] In the present invention, the dropping time is preferably 1 to 6 hours, more preferably 2 to 5 hours, and more preferably 3 to 4 hours.

[0103] In the present invention, the reaction temperature is preferably 65 to 95°C, more preferably 70 to 90°C, and more preferably 75 to 85°C.

[0104] In the present invention, the temperature of the heat preservation reaction is preferably 85-95°C, more preferably 87-93°C, and more preferably 89-91°C.

[0105] In the present invention, the insulation reaction time is preferably 0.5 to 2 hours, more preferably 0.8 to 1.7 hours, and more preferably 1.1 to 1.4 hours.

[0106] In the present invention, the post-polymerization alkali neutralization process comprises the following steps:

[0107] (1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer to obtain a miscible solution;

[0108] (2) adding the initiator aqueous solution and the miscible solution to the solvent under the action of a protective gas at a reaction temperature, reacting the mixture, and then keeping the temperature to react to obtain an intermediate system;

[0109] (3) Adding an alkaline neutralizing agent to the intermediate system obtained in the above step for neutralization to obtain a water-soluble resin film-forming agent.

[0110] The invention firstly mixes acrylic acid, unsaturated carboxylic acid containing double bonds and / or unsaturated anhydride containing double bonds, cohesive monomers, viscous monomers and functional monomers to obtain a mixed solution.

[0111] The present invention then adds the initiator aqueous solution and the mixed solution into the solvent under the action of protective gas and at the reaction temperature, and then reacts, and then heats the reaction to obtain an intermediate system.

[0112] In the present invention, the temperature of the intermediate system is preferably equal to or less than 60°C, more preferably equal to or less than 55°C, and more preferably equal to or less than 50°C.

[0113] In the present invention, the pH value of the neutralization is preferably controlled at 2 to 7.5, more preferably 3 to 6.5, and more preferably 4 to 5.5.

[0114] In the present invention, the initiator preferably includes a thermal initiation system initiator or a redox system initiator.

[0115] In the present invention, the percentage of the thermal initiation system initiator to the monomer mass is preferably 0.05% to 5%, more preferably 0.5% to 4%, more preferably 1% to 3%, more preferably 1.5% to 2%.

[0116] In the present invention, the thermal initiation system initiator preferably includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, diisopropylbenzene peroxide, azobisisobutyronitrile and azobisisoheptylonitrile, more preferably ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, diisopropylbenzene peroxide, azobisisobutyronitrile or azobisisoheptylonitrile.

[0117] In the present invention, the percentage of the redox system initiator to the monomer mass is preferably 0.05% to 5%, more preferably 0.5% to 4%, more preferably 1% to 3%, more preferably 1.5% to 2%.

[0118] In the present invention, the redox system initiator preferably includes an oxidizing agent and a reducing agent.

[0119] In the present invention, the molar ratio of the oxidizing agent to the reducing agent is preferably 1:(0.5-1), more preferably 1:(0.6-0.9), and more preferably 1:(0.7-0.8).

[0120] In the present invention, the oxidant preferably includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide and tert-butyl hydroperoxide, more preferably ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide or tert-butyl hydroperoxide.

[0121] In the present invention, the reducing agent preferably includes one or more of sodium sulfite, sodium bisulfite, sodium pyrosulfite and sodium formaldehyde sulfoxylate, more preferably sodium sulfite, sodium bisulfite, sodium pyrosulfite or sodium formaldehyde sulfoxylate.

[0122] In the present invention, the monomers preferably include acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated acid anhydride containing a double bond, cohesive monomers, adhesive monomers and functional monomers.

[0123] In the present invention, an alkaline neutralizing agent is finally added to the intermediate system obtained in the above steps for neutralization to obtain a water-soluble resin film-forming agent.

[0124] The present invention provides use of the water-soluble resin film-forming agent described in any one of the above technical solutions or the water-soluble resin film-forming agent prepared by the preparation method described in any one of the above technical solutions in glass fiber processing.

[0125] In the present invention, the glass fiber treatment preferably includes a treatment for improving the surface properties of the glass fiber.

[0126] In the present invention, the application preferably includes application in the preparation process of glass fiber reinforced PA (nylon) composite materials.

[0127] The present invention provides a sizing agent for glass fiber, the sizing agent comprising a film-forming agent, a coupling agent, a second film-forming agent, a cross-linking agent and a lubricant;

[0128] The film-forming agent includes the water-soluble resin film-forming agent described in any one of the above technical solutions or the water-soluble resin film-forming agent prepared by the preparation method described in any one of the above technical solutions.

[0129] The present invention is to complete and refine the overall technical solution, better ensure the composition and performance of the film-forming agent, further improve the compatibility of glass fiber and nylon resin in glass fiber composite materials and the mechanical properties of the composite materials. The above-mentioned active group-rich water-soluble resin film-forming agent for glass fiber and its preparation method may specifically include the following contents:

[0130] The preparation method of a water-soluble resin film-forming agent rich in active groups for glass fiber comprises the following steps:

[0131] Each comonomer is prepared by solution polymerization process under the conditions of initiator, nitrogen protection, heating and stirring, and the mass ratio of raw materials of synthetic resin formula is:

[0132] Component A: acrylic acid 15% to 55%;

[0133] Component B: containing 1% to 20% of double-bond unsaturated carboxylic acid (anhydride), including one or more of methacrylic acid, methylene succinic acid (itaconic acid), maleic anhydride (maleic anhydride), and maleic acid (maleic acid).

[0134] Component C: 1% to 10% of the cohesive monomer, including one or more of vinyl acetate, methyl acrylate, and methyl methacrylate.

[0135] Component D: 1% to 10% of a viscous monomer, including one or more of butyl acrylate, 2-ethylhexyl acrylate, and isooctyl acrylate.

[0136] Component E: 0.1% to 6% of functional monomers, one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, glycidyl methacrylate, N-hydroxymethyl acrylamide, sodium vinyl sulfonate, and sodium styrene sulfonate.

[0137] Component F: The amount of alkaline neutralizer is to control the pH of the system to 2-7.5, including one or more of sodium hydroxide, ammonia water, and organic amines.

[0138] Component G: 40% to 80% solvent, including one or more of water, methanol, ethanol, propanol, isopropanol, butanol and isobutanol.

[0139] Specifically, the solution polymerization process can be carried out in one of the following two ways:

[0140] (1) Alkali neutralization process before polymerization

[0141] S1: Weigh the monomers according to the ratio and mix them to dissolve each other, then weigh the alkaline neutralizer according to the ratio and slowly add it to the mixed monomers, stirring while adding until they are completely dissolved, and cool the system to control the temperature below 40°C during the dissolution process;

[0142] S2: preparing an initiator aqueous solution according to a ratio of water to initiator, wherein the mass ratio of water to initiator is 10:1 to 100:1;

[0143] S3: Add the solvent in the reaction kettle according to the proportion, stir and heat to the reaction temperature through nitrogen, add the mixed monomer and initiator prepared in S1 dropwise for 1 to 6 hours, the reaction temperature is 65 to 95°C, keep the temperature at 85 to 95°C for 0.5 to 2 hours after the addition, cool the material, filter and obtain the product.

[0144] (2) Post-polymerization alkali neutralization process

[0145] S1: weigh the monomers according to the ratio and mix them to dissolve each other;

[0146] S2: preparing an initiator aqueous solution according to a ratio of water to initiator, wherein the mass ratio of water to initiator is 10:1 to 100:1;

[0147] S3: Add the proportion solvent into the reactor according to the proportion, stir and heat to the reaction temperature with nitrogen, dropwise add the mixed monomer and initiator prepared in S1 for reaction, the dropwise addition time is 1 to 6 hours, the reaction temperature is 65 to 95°C, after the dropwise addition is completed, keep the temperature at 85 to 95°C for 0.5 to 2 hours, and then cool to below 60°C;

[0148] S4: Weigh the alkaline neutralizer according to the formula and slowly add it into the reactor for neutralization, stirring while adding until they are completely miscible, cool the material, filter and obtain the product.

[0149] Specifically, the initiator is selected according to the two initiation methods adopted:

[0150] (1) A thermal initiation system is used, wherein the initiator accounts for 0.05% to 5% of the monomer mass ratio, including one or more of ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, diisopropylbenzene peroxide, azobisisobutyronitrile, and azobisisoheptylnitrile.

[0151] (2) A redox system may also be used, where the initiator is a combination of one or more oxidants and one or more reductants, wherein the oxidant accounts for 0.05% to 5% of the monomer mass ratio, and the molar ratio of the oxidant to the reductant is 1:1 to 1:0.5. The oxidant includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide, and tert-butyl hydroperoxide; the reductant includes one or more of sodium sulfite, sodium bisulfite, sodium pyrosulfite, and sodium formaldehyde sulfoxylate (Diaobaikuai). The oxidant and the reductant are separately prepared and added separately.

[0152] Specifically, the organic amines in the alkaline neutralizer are: fatty amines include diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, etc., and alcohol amines include ethanolamine, diethanolamine, triethanolamine, etc., one or more of them.

[0153] Specifically, the water-soluble resin has a weight average molecular weight of 1,000 to 200,000.

[0154] Further:

[0155] Each comonomer of the present invention is prepared by a solution polymerization process under the conditions of initiator, nitrogen protection, heating and stirring. The synthesis preparation method can adopt an alkali neutralization process before polymerization or an alkali neutralization process after polymerization, as follows:

[0156] (1) Alkali neutralization process before polymerization

[0157] S1: Weigh the monomers according to the ratio and mix them to dissolve each other, then weigh the alkaline neutralizer according to the ratio and slowly add it to the mixed monomers, stirring while adding until they are completely dissolved, and cool the system to control the temperature below 40°C during the dissolution process;

[0158] S2: preparing an initiator aqueous solution according to a ratio of water to initiator, wherein the mass ratio of water to initiator is 10:1 to 100:1;

[0159] S3: Add the solvent in the reaction kettle according to the proportion, stir and heat to the reaction temperature through nitrogen, add the mixed monomer and initiator prepared in S1 dropwise for 1 to 6 hours, the reaction temperature is 65 to 95°C, keep the temperature at 85 to 95°C for 0.5 to 2 hours after the addition, cool the material, filter and obtain the product.

[0160] (2) Post-polymerization alkali neutralization process

[0161] S1: weigh the monomers according to the ratio and mix them to dissolve each other;

[0162] S2: preparing an initiator aqueous solution according to a ratio of water to initiator, wherein the mass ratio of water to initiator is 10:1 to 100:1;

[0163] S3: Add the proportion solvent into the reactor according to the proportion, stir and heat to the reaction temperature with nitrogen, dropwise add the mixed monomer and initiator prepared in S1 for reaction, the dropwise addition time is 1 to 6 hours, the reaction temperature is 65 to 95°C, after the dropwise addition is completed, keep the temperature at 85 to 95°C for 0.5 to 2 hours, and then cool to below 60°C;

[0164] S4: Weigh the alkaline neutralizer according to the formula and slowly add it into the reactor for neutralization, stirring while adding until they are completely miscible, cool the material, filter and obtain the product.

[0165] In the above synthesis process, the raw material quality ratio of the synthetic resin formula is as follows:

[0166] Component A: 15% to 55% acrylic acid. Acrylic acid, as the main monomer of the present invention, can provide excellent synthesis stability, meet the design performance requirements of the film-forming agent, and has a relatively low cost.

[0167] Component B: Contains 1% to 20% of double-bond unsaturated carboxylic acid (anhydride), including one or more of methacrylic acid, methylene succinic acid (itaconic acid), maleic anhydride (maleic anhydride), and maleic acid (maleic acid). By introducing different double-bond unsaturated carboxylic acid (anhydride) monomers, the carboxylic acid density in the polymer molecular structure can be adjusted over a wide range, and at the same time, the molecular weight, film-forming properties and glass fiber properties of the high molecular polymer have a large optimization adjustment space, enriching the application range of the series of film-forming agents of the present invention.

[0168] Component C: 1% to 10% of cohesive monomer, including one or more of vinyl acetate, methyl acrylate, and methyl methacrylate. The introduction of such monomers can adjust the mechanical properties of polymer film formation within a certain range and give the glass fiber the necessary processing properties.

[0169] Component D: 1% to 10% of adhesive monomers, including one or more of butyl acrylate, 2-ethylhexyl acrylate, and isooctyl acrylate. The introduction of such monomers can improve the bundling performance of the film-forming agent on the glass fiber, adjust the hardness of the film-forming agent and the glass fiber yarn, and improve the short-cut performance.

[0170] Component E: 0.1% to 6% functional monomer, one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, glycidyl methacrylate, N-hydroxymethyl acrylamide, sodium vinyl sulfonate, and sodium styrene sulfonate. The introduction of functional monomers, on the one hand, gives the film-forming agent more cross-linking properties, improves the unique mechanical properties of the film-forming agent and glass fiber yarn, and at the same time, some functional monomers can further adjust the water solubility of the polymer.

[0171] Component F: The amount of alkaline neutralizer is to control the pH value of the system to 2-7.5, including one or more of sodium hydroxide, ammonia water, and organic amines. The organic amines in the alkaline neutralizer are: fatty amines including diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, etc., and alcohol amines including ethanolamine, diethanolamine, triethanolamine, etc., one or more of them.

[0172] Component G: 40% to 80% solvent, including one or more of deionized water, methanol, ethanol, propanol, isopropanol, butanol, and isobutanol.

[0173] The water-soluble resin prepared by the above process and formula has a synthetic molecular weight controlled at 1000 to 200000. If the molecular weight is too low, the film-forming performance is poor; if the molecular weight is too high, the water solubility of the resin becomes poor, the viscosity of the aqueous solution is too high, or agglomeration gel is easily formed during the synthesis process.

[0174] In the solution polymerization process, the initiator can choose to use one of the following two initiation methods:

[0175] (1) A thermal initiation system is used: the initiator accounts for 0.05% to 5% of the monomer mass ratio, including one or more of ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, diisopropylbenzene peroxide, azobisisobutyronitrile, and azobisisoheptylnitrile.

[0176] (2) A redox system can also be used: the initiator is a combination of one or more oxidants and one or more reductants, wherein the oxidant accounts for 0.05% to 5% of the monomer mass ratio, and the molar ratio of the oxidant to the reductant is 1:1 to 1:0.5. The oxidant includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide, and tert-butyl hydroperoxide; the reductant includes one or more of sodium sulfite, sodium bisulfite, sodium pyrosulfite, and sodium formaldehyde sulfoxylate (Diaobaikuai). The oxidant and the reductant are separately prepared and added separately.

[0177] The above content of the present invention provides a water-soluble resin film-forming agent rich in active groups for glass fiber, and its preparation method, application, and a wetting agent for glass fiber. The present invention uses a carboxylic acid monomer containing unsaturated double bonds as the main monomer and prepares the film-forming agent through a solution polymerization process. On the one hand, this type of high molecular polymer forms a uniform film after drying and dehydration, and can fully meet the glass fiber's requirements for the processing performance of the film-forming agent after molecular weight control and copolymerization by adding modified monomers through the synthesis process; on the other hand, the carboxylic acid monomer with unsaturated double bonds can provide a large number of highly polar and reactive active groups for the film-forming agent, which is beneficial to provide a reaction bridge for the coupling agent and the film-forming agent, thereby greatly improving the performance of the composite material; on the other hand, the polymer film-forming agent is endowed with certain hydrophilic functional groups, and after reacting with an alkaline neutralizer, an ionic hydrophilic structure can be formed in water, which ultimately gives the film-forming agent good water solubility, which is beneficial to the uniform coating of the film-forming agent on the surface of the glass fiber, and is environmentally friendly.

[0178] The water-soluble resin film-forming agent rich in active groups for glass fiber provided by the present invention can provide processing properties such as the required bundling and low hairiness of glass fiber on the one hand, and give glass fiber good compatibility with nylon resin on the other hand. The key to the film-forming agent of the present invention is that it has abundant active groups, strong polarity and reactivity, which is conducive to providing a bridge for the reaction of coupling agents and film-forming agents, thereby greatly improving the performance of composite materials, and the prepared glass fiber reinforced PA composite material has excellent performance. The present invention is particularly suitable for the main (or secondary) film-forming agent for glass fiber for reinforcing nylon resin. It can be used as a special sizing agent for coating glass fiber to improve the surface properties of glass fiber when used in combination with other components in the sizing agent. As a film-forming agent in the glass fiber sizing agent, it is particularly suitable for the glass fiber film-forming agent for reinforcing nylon resin, providing good protection for glass fiber in the glass fiber preparation process, and the abundant active groups can react and combine with the relevant active groups in the sizing agent and the matrix resin. The prepared glass fiber has good interface strength with various matrix resins, and the glass fiber composite has good mechanical properties, water resistance, UV aging resistance, and thermal oxidation resistance.

[0179] The experimental results show that the active group-rich water-soluble resin film-forming agent provided by the present invention is used in combination with other sizing agent components such as coupling agents, second film-forming agents, cross-linking agents, lubricants, etc., and the drawing operation is stable in the glass fiber manufacturing process, the glass fiber coating effect is good, the glass fiber production is smooth, and it has the advantages of good short-cutting property, fluidity, and less hairiness. Moreover, the prepared glass fiber has good compatibility and interface strength with the composite matrix resin, and the prepared composite material has excellent mechanical properties. The tensile strength, bending strength, and impact strength of the spline are significantly improved compared with conventional sizing agent formulas, and the boiling resistance, UV resistance, and thermal oxidation resistance are improved.

[0180] To further illustrate the present invention, a water-soluble resin film-forming agent for glass fiber provided by the present invention, a preparation method thereof, applications, and a wetting agent for glass fiber are described in detail below in conjunction with embodiments. However, it should be understood that these embodiments are implemented on the premise of the technical scheme of the present invention, and detailed implementation methods and specific operating procedures are given only to further illustrate the features and advantages of the present invention, rather than to limit the claims of the present invention, and the protection scope of the present invention is not limited to the embodiments described below.

[0181] Example 1

[0182] Step 1: Weigh 200g of acrylic acid, 100g of methacrylic acid, 15g of methyl acrylate, 20g of butyl acrylate, and 10g of glycidyl acrylate respectively, mix and dissolve them, then weigh 45g of 25% ammonia water, an alkaline neutralizer, according to the ratio and slowly add it to the mixed monomers, stirring while adding until they are completely dissolved, and cool down the system temperature to control it below 40°C during the dissolution process;

[0183] Step 2: Weigh 7 g of initiator ammonium persulfate and dissolve it in water to prepare 100 g of initiator aqueous solution;

[0184] Step 3: Add 510g of deionized water to the reactor, stir and heat to 80°C with nitrogen, add the mixed monomer prepared in step 1 and the initiator solution in step 2 dropwise for 2 hours at a reaction temperature of 80±2°C. After the addition is complete, keep the reaction at 90±2°C for 1 hour, cool the material, filter and obtain the product with a solid content of 36.3%.

[0185] Example 2

[0186] Step 1: Weigh 240g of acrylic acid, 60g of methacrylic acid, 40g of itaconic acid, 30g of vinyl acetate, 20g of butyl acrylate, and 10g of hydroxyethyl acrylate respectively, mix and dissolve them, then weigh 50g of alkaline neutralizer isopropylamine according to the ratio and slowly add it to the mixed monomers, stirring while adding until they are completely dissolved, and cool down the system temperature to control it below 40°C during the dissolution process;

[0187] Step 2: Weigh 10 g of the initiator tert-butyl hydroperoxide and dissolve it in water to prepare 100 g of an oxidative initiator aqueous solution, and weigh 7.5 g of bleaching powder and dissolve it in water to prepare 100 g of a reductive initiator aqueous solution;

[0188] Step 3: Add 350g of deionized water to the reactor, stir and heat to 75°C with nitrogen, add the mixed monomer prepared in step 1 and the initiator solution in step 2 dropwise for 3 hours at a reaction temperature of 75±2°C. After the addition is complete, keep the reaction at 90±2°C for 1 hour, cool the material, filter and obtain the product with a solid content of 46.5%.

[0189] Example 3

[0190] Step 1: Weigh 170 g of acrylic acid, 30 g of methacrylic acid, 20 g of vinyl acetate, 20 g of butyl acrylate, 10 g of glycidyl methacrylate, and 5 g of hydroxyethyl acrylate respectively, mix and dissolve each other to form a mixed monomer;

[0191] Step 2: weigh 12.5 g of initiator sodium persulfate and dissolve it in water to prepare 100 g of initiator aqueous solution;

[0192] Step 3: Add 400g of deionized water, 200g of isopropanol, and 20g of maleic anhydride into a reactor, stir under nitrogen and heat to 85°C (maleic anhydride dissolves during the process), then dropwise add the mixed monomer prepared in step 1 and the initiator solution in step 2 for 4 hours at a reaction temperature of 85±2°C, and keep the reaction at 90±2°C for 1 hour after the dropwise addition is completed;

[0193] Step 4: After the heat preservation is completed, the temperature is lowered to below 60°C and diethylamine is slowly added dropwise under stirring to adjust the pH value of the system to 3-4. The temperature is lowered, the material is discharged and filtered to obtain the product. The resin solid content is 35.5%.

[0194] The glass fiber active group-rich water-soluble resin film-forming agent 6.0% prepared in Examples 1 to 3 of the present invention, the polyurethane film-forming agent 6.0%, the coupling agent 0.95% (γ-aminotriethoxysilane), the lubricant 0.05% (polyethylene glycol 400 monostearate), the cross-linking agent 1%, and the deionized water 86.0% were respectively configured into a wetting agent according to the general industry method.

[0195] Meanwhile, in the comparative example, only 12% of the polyurethane film-forming agent is used as the film-forming agent to prepare the wetting agent, and other wetting agent components are the same.

[0196] The above four groups of sizing agents were applied to the production of glass fibers, and the corresponding glass fibers were dried and chopped into chopped strands. At the same time, the drawing process, hairiness, fluidity, and chopped performance in the glass fiber production process were evaluated. The corresponding chopped glass fiber products were then melt-blended and granulated with nylon resin using a twin-screw extrusion process to produce glass fiber reinforced nylon resin pellets, and composite material test specimens were made using an injection molding process. The following evaluation methods were used to conduct a comprehensive evaluation of the composite material performance:

[0197] (1) The tensile strength and modulus are tested according to ISO527 standard;

[0198] (2) Flexural strength and modulus are tested using ISO178 test standard;

[0199] (3) Impact strength adopts ISO179 Charpy test standard;

[0200] (4) Boiling conditions: The tensile strength retention rate of the specimens was tested after boiling in water at a ratio of 1:1 water to ethylene glycol and a temperature of 120°C for 48 hours;

[0201] (5) UV aging conditions: light wavelength 50 nm, temperature 50°C, irradiation for 480 hours, and then test the tensile strength retention rate of the specimens;

[0202] (6) Thermal oxidative aging test conditions: The tensile strength retention rate of the test specimens was tested after aging at 150°C for 480 hours.

[0203] See Table 1, which shows the comparative test results of the production processes for preparing glass fiber reinforced nylon resins in the embodiments and comparative examples provided by the present invention.

[0204] Table 1

[0205] Film former Wetting agent Wire drawing Oiling rate m / min Hairiness g / curl Short Cut Liquidity Example 1 Stablize Stablize 20 0.08 good good Example 2 Stablize Stablize 20 0.09 good good Example 3 Stablize Stablize 20 0.08 good good Comparative Example Stablize Stablize 20 0.13 good good

[0206] See Table 2, which shows the comparative performance test results of the glass fiber reinforced nylon resin composite materials prepared in the embodiments and comparative examples provided by the present invention.

[0207] Table 2

[0208]

[0209] It can be seen from the above results that the active group-rich water-soluble resin film-forming agent for glass fiber prepared by the present invention can be used in combination with other sizing agent components such as coupling agent, second film-forming agent, cross-linking agent, lubricant, etc. to prepare a sizing agent with good compounding performance. The film-forming agent of the present invention has stable wire drawing operation, good coating effect on glass fiber, smooth glass fiber production, good short-cutting property, fluidity, low hairiness, etc. Moreover, the prepared glass fiber has good compatibility and interface strength with the composite matrix resin, and excellent mechanical properties.

[0210] The above is a detailed introduction to a kind of active group-rich water-soluble resin film-forming agent for glass fiber provided by the present invention, its preparation method, application, and a sizing agent for glass fiber. The principle and implementation method of the present invention are described in detail using specific examples in this article. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention, including the best mode, and also enables any technician in the field to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified in several ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements that are not different from the textual expression of the claims, or if they include equivalent structural elements that are not substantially different from the textual expression of the claims, then these other embodiments should also be included in the scope of the claims.

Claims

1. A water-soluble resin film-forming agent for glass fiber, characterized in that: Calculated by weight of raw materials, including: Acrylic acid 15-55 parts by weight; 1-20 parts by weight of unsaturated carboxylic acid containing a double bond and / or unsaturated acid anhydride containing a double bond; 1-10 parts by weight of cohesive monomer; 1-10 parts by weight of adhesive monomer; 1-10 parts by weight of functional monomer; 40-80 parts by weight of solvent; Alkaline neutralizer; The alkaline neutralizer is used in an amount to control the pH value of the system to be 2-7.5; The cohesive monomer includes one or more of vinyl acetate, methyl acrylate and methyl methacrylate; The adhesive monomer includes one or more of butyl acrylate, 2-ethylhexyl acrylate and isooctyl acrylate; The functional monomers include one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl acrylate, glycidyl methacrylate, N-hydroxymethyl acrylamide, sodium vinyl sulfonate and sodium styrene sulfonate; The water-soluble resin film-forming agent is a water-soluble resin film-forming agent rich in active groups; The water-soluble resin film-forming agent is prepared from raw materials by a solution polymerization process under nitrogen protection, heating and stirring conditions.

2. The water-soluble resin film-forming agent according to claim 1, characterized in that The double-bond-containing unsaturated carboxylic acid includes one or more of methacrylic acid, itaconic acid and maleic acid; The double bond-containing unsaturated anhydride includes maleic anhydride; The weight average molecular weight of the water-soluble resin film-forming agent is 1,000 to 200,000.

3. The water-soluble resin film-forming agent according to claim 1, characterized in that The alkaline neutralizing agent includes one or more of sodium hydroxide, ammonia water and organic amine compounds; The organic amine compound includes one or more of diethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec-butylamine, ethanolamine, diethanolamine and triethanolamine.

4. The water-soluble resin film-forming agent according to claim 1, characterized in that The solvent includes one or more of water, methanol, ethanol, propanol, isopropanol, butanol and isobutanol; The raw materials also include an initiator; The solution polymerization process includes an alkali neutralization process before polymerization or an alkali neutralization process after polymerization.

5. A method for preparing a water-soluble resin film-forming agent for glass fiber according to any one of claims 1 to 4, characterized in that: The preparation method includes a pre-polymerization alkali neutralization process or a post-polymerization alkali neutralization process; The pre-polymerization alkali neutralization process comprises the following steps: 1) acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, an adhesive monomer and a functional monomer are mixed, and then an alkaline neutralizing agent is added to mix and dissolve to obtain a miscible solution; 2) Under the action of protective gas and at the reaction temperature, the initiator aqueous solution and the mixed solution are added to the solvent for reaction, and then the reaction is kept at the temperature to obtain a water-soluble resin film-forming agent; The post-polymerization alkali neutralization process comprises the following steps: (1) mixing acrylic acid, unsaturated carboxylic acid containing a double bond and / or unsaturated anhydride containing a double bond, an endoplasmic monomer, a viscous monomer and a functional monomer to obtain a mixed solution; (2) Under the action of protective gas and at the reaction temperature, the initiator aqueous solution and the miscible solution are added to the solvent to react, and then the reaction is kept at the temperature to obtain an intermediate system; (3) An alkaline neutralizing agent is added to the intermediate system obtained in the above step for neutralization to obtain a water-soluble resin film-forming agent.

6. The preparation method according to claim 5, characterized in that: The specific methods of adding the alkaline neutralizer in step (1) and step (3) are independently selected from: slowly adding the alkaline neutralizer while stirring until it is completely dissolved; The miscibility temperature in step 1) is less than or equal to 40°C; In the initiator aqueous solution, the mass ratio of water to initiator is (10-100):1; The initiator aqueous solution and the miscible solution are added to the solvent in a manner including dropwise addition; The time of the dropping is 1 to 6 hours.

7. The preparation method according to claim 5, characterized in that: The reaction temperature is 65-95°C; The temperature of the insulation reaction is 85-95°C; The insulation reaction time is 0.5 to 2 hours; The temperature of the intermediate system is less than or equal to 60°C; The pH value of the neutralization is controlled at 2-7.

5.

8. The preparation method according to claim 5, characterized in that: The initiator includes a thermal initiation system initiator or a redox system initiator; The percentage of the thermal initiation system initiator to the monomer mass is 0.05% to 5%; The thermal initiation system initiator includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile and azobisisoheptylnitrile; The redox system initiator accounts for 0.05% to 5% of the monomer mass; The redox system initiator comprises an oxidant and a reductant; The molar ratio of the oxidant to the reductant is 1:(0.5~1); The oxidant includes one or more of ammonium persulfate, potassium persulfate, sodium persulfate, hydrogen peroxide and tert-butyl hydroperoxide; The reducing agent includes one or more of sodium sulfite, sodium bisulfite, sodium pyrosulfite and sodium formaldehyde sulfoxylate.

9. Use of the water-soluble resin film-forming agent according to any one of claims 1 to 4 or the water-soluble resin film-forming agent prepared by the preparation method according to any one of claims 5 to 8 in glass fiber processing.

10. A sizing agent for glass fiber, characterized in that: The wetting agent includes a film-forming agent, a coupling agent, a second film-forming agent, a cross-linking agent and a lubricant; The film-forming agent comprises the water-soluble resin film-forming agent described in any one of claims 1 to 4 or the water-soluble resin film-forming agent prepared by the preparation method described in any one of claims 5 to 8.

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