CN106634417B

CN106634417B - Industrial legacy steel structure surface layer protective agent and preparation method and application thereof

Info

Publication number: CN106634417B
Application number: CN201611116779.9A
Authority: CN
Inventors: 王东林; 何鸣; 赵希娟; 徐雪萍; 王霜
Original assignee: Central Research Institute of Building and Construction Co Ltd MCC Group; China Jingye Engineering Corp Ltd
Current assignee: Central Research Institute of Building and Construction Co Ltd MCC Group; China Jingye Engineering Corp Ltd
Priority date: 2016-12-07
Filing date: 2016-12-07
Publication date: 2020-06-09
Anticipated expiration: 2036-12-07
Also published as: CN106634417A

Abstract

The invention relates to a protective agent for a steel structure surface layer of industrial heritage, a preparation method and application thereof, and belongs to the field of protection of steel structures of industrial heritage. Comprises the following components in percentage by weight: 27-41% of plastic resin liquid, 15-25% of dispersing agent, 4-18% of penetrating agent, 5-10% of anti-ultraviolet aging agent, 13-30% of film-forming assistant and 9-35% of active solvent. The agent has good weather resistance, sun resistance, water resistance and excellent matting property. After the application, the protective performance is high, and the light-reflecting and dazzling-free protective film is not reflected. The product is used for protecting and developing industrial sites and protecting steel surfaces. The adhesive force of the coating is improved and ensured by permeating and sealing gaps, joints and splicing parts of the structural member and stress change caused by the old rust layer and the old coating, and the service life of the maintenance system is prolonged.

Description

Industrial legacy steel structure surface layer protective agent and preparation method and application thereof

Technical Field

The invention relates to a protective agent for a steel structure surface layer of industrial heritage, a preparation method and application thereof, and belongs to the field of protection of steel structures of industrial heritage.

Background

The industrial heritage is frequently generated, the shape of a steel structure is complex, and substances on the surface of a base layer are complex and various. The structure forms are various. And the protective requirements of decades or even hundreds of years are provided, the culture heritage is reserved, and in the past, a plurality of medium environments with acid, alkali and salt corrosion exist. The long-term erosion of ultraviolet rays, carbon dioxide in the air, haze, rainwater and the like is overcome.

Disclosure of Invention

The purpose of the invention is: provides a protective agent for a steel structure surface layer of industrial heritage and a preparation method and application thereof.

According to a first aspect of the invention, the protective agent for the steel structure base layer of the industrial heritage comprises the following components in parts by weight: 7-10% of crystalline resin liquid, 25-30% of epoxy resin, 5-15% of curing agent, 3-5% of dispersing agent, 3-8% of penetrating agent, 3-10% of corrosion inhibitor, 3-10% of film forming additive and 13-25% of active solvent.

The crystalline resin liquid is preferably acrylic modified polypropylene crystalline resin emulsion.

The penetrating agent is penetrating agent BX, penetrating agent T or penetrating agent JFC.

The preparation method of the base layer protective agent comprises the following steps: adding crystalline resin liquid and epoxy resin into a reaction kettle, heating and stirring, adding a dispersing agent, a penetrating agent, a corrosion inhibitor, a film forming auxiliary agent and an active solvent, carrying out polymerization reaction, and controlling the temperature and time to finally finish the polymerization reaction.

According to a second aspect of the invention, the industrial legacy steel structure interlayer connecting agent comprises the following components in parts by weight: 25-30% of coupling agent modified coating resin liquid, 25-30% of epoxy resin, 15-30% of curing agent, 1-2% of dispersing agent, 2-5% of penetrating agent, 9-25% of film forming additive, 4-20% of active solvent and 2-8% of second coupling agent.

The coupling agent modified coating resin liquid is modified by copolymerization of at least one first coupling agent and at least one other monomer; as the first coupling agent, a titanate coupling agent can be used.

The second coupling agent may employ a silane coupling agent such as KH550, KH570 or the like, or a titanate coupling agent or the like.

The preparation method of the middle layer protective agent can be that according to the formula, coating resin liquid modified by coupling agent, epoxy resin and dispersing agent are added through a reaction kettle, stirring and heating are carried out, then synthetic penetrating agent, film forming auxiliary agent, active solvent and coupling agent are added, the temperature and time are controlled, and finally the polymerization reaction is finished. When in use, the reactant is mixed with the curing agent.

According to a third aspect of the invention, the protective agent for the steel structure surface layer of the industrial heritage comprises the following components in percentage by weight: 27-41% of plastic resin liquid, 15-25% of dispersing agent, 4-18% of penetrating agent, 5-10% of anti-ultraviolet aging agent, 13-30% of film-forming assistant and 9-35% of active solvent.

The plastic resin liquid can adopt acrylic acid modified polyethylene terephthalate, poly toluene diisocyanate and the like.

According to the formula, the plastic resin liquid and the dispersing agent are added into a reaction kettle, then stirring and heating are carried out, the penetrating agent, the ultraviolet aging resistant agent, the film forming auxiliary agent and the active solvent are added for synthesis, the temperature and the time are controlled, and finally the polymerization reaction is finished.

The invention also provides application of the surface layer protective agent in surface protection of industrial heritage.

According to a fourth aspect of the invention, a long-acting comprehensive protection method for an industrial legacy steel structure comprises the following steps:

step 1, removing surface dirt on the surface of a steel structure of industrial heritage;

step 2, spraying a base layer protective agent on the surface of the steel structure treated in the step 1;

step 3, spraying an intermediate layer protective agent on the surface of the steel structure treated in the step 2;

and 4, spraying a surface layer protective agent on the surface of the steel structure treated in the step 3.

In the step 2, the curing time after spraying is more than 36 hours, the performance of the protective layer is tested, and the step 3 is carried out after the set requirement is met; if the setting requirement is not met, repeating the step 2.

In the step 2, the curing time after spraying is more than 24 hours, the performance of the protective layer is tested, and the step 4 is carried out after the set requirement is met; if the setting requirement is not met, repeating the step 3.

In the step 4, the spraying frequency of the surface layer protective agent is more than two times, the interval time between every two times of spraying is 12-24 hours, the spraying is not carried out in rainy and snowy days, and the environmental temperature is required to be more than 5 ℃.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments. It will be understood by those skilled in the art that the following examples are illustrative of the present invention only and should not be taken as limiting the scope of the invention. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.

Furthermore, ordinal terms such as "first," "second," "third," etc., used in the claims and the specification are used to modify a claim term without necessarily implying any order of precedence, or order of any claim prior to or with respect to another claim or the order in which method steps are performed. However, merely used as a label to distinguish one element of a claim having a particular name from another element having the same name (rather than being sequentially owned), to distinguish the elements of the claim. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

The words "include," "have," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The recitation of values by ranges is to be understood in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a concentration range of "about 0.1% to about 5%" should be interpreted to include not only the explicitly recited concentration of about 0.1% to about 5%, but also include individual concentrations (e.g., 1%, 2%, 3%, and 4%) and sub-ranges (e.g., 0.1% to 0.5%, 1% to 2.2%, 3.3% to 4.4%) within the indicated range.

The percentages recited in the present invention refer to weight percentages unless otherwise specified.

The invention provides a permeable protective coating applied to steel structures or stone materials of industrial heritage, and the coating consists of 3 layers (a base layer, a middle layer and a surface layer) of coating compositions.

Coating a base layer:

the high-performance, two-component and chemically-cured high-performance penetration-stable protective agent comprises the following components in parts by weight: 7-10% of crystalline resin liquid, 25-30% of epoxy resin, 5-15% of curing agent, 3-5% of dispersing agent, 3-8% of penetrating agent, 3-10% of corrosion inhibitor, 3-10% of film forming additive and 13-25% of active solvent. The curing agent is used for quickly curing the coating after being mixed with the coating prepared from other components, and the other components are main components for preparing the base layer protective agent.

The crystalline resin liquid has good adsorption with the base layer, can eliminate internal stress and well transfer stress, and has the effects of enhancing tensile strength, shear strength and impact strength; in a preferred embodiment, a modified polypropylene crystalline resin solution is used, wherein the modified polypropylene crystalline resin solution can be prepared by modification methods in the known art, mainly by adding a modifying monomer during polymerization for grafting, for example, an acrylic modified polypropylene crystalline resin emulsion can be used, and the acrylic modified polypropylene emulsion in the following examples is prepared by the following method:

in step 1, 0.3 part by weight of dibenzoyl peroxide (BPO) is dissolved in an acrylic monomer mixture (the weight ratio of m (methyl methacrylate) to m (N-methylolacrylamide) to m (butyl acrylate) to m (methacrylic acid) is 50: 14: 18).

Step 2, 100g of polypropylene and 150mL of toluene are added to a 1000mL four-necked round-bottomed flask under nitrogen and heated to 100 ℃ to dissolve the polypropylene and the toluene. And (3) maintaining the temperature, slowly dripping 12g of the mixed solution obtained in the step 1 for about 1 hour, and then maintaining the temperature to continue the reaction for 3.5 hours. After the reaction is finished, cooling to 60 ℃, dropwise adding a 10% aqueous solution of Dimethylaminoethanol (DMAE) to a pH value of 7-8 while stirring, and stirring for 30min to fully disperse the DMAE. Slowly dropping 300g of distilled water into the system under high-speed stirring to form uniformly dispersed emulsion, continuously dispersing for 50min, adding 6g of surface wetting agent, and uniformly dispersing to obtain the acrylic acid modified polypropylene crystalline resin emulsion.

The epoxy resin in the above composition is not particularly limited, and examples thereof include: bisphenol a-type epoxy resins, bisphenol F-type epoxy resins, phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, bisphenol a novolac-type epoxy resins, 3-functional phenol-type epoxy resins, naphthalene-type epoxy resins, biphenyl-type epoxy resins, aralkyl novolac-type epoxy resins, alicyclic epoxy resins, polyhydric alcohol-type epoxy resins, glycidyl amines, glycidyl esters, compounds obtained by epoxidizing double bonds of butadiene and the like, compounds obtained by reacting hydroxyl group-containing silicone resins with epichlorohydrin, and the like.

The type of the curing agent used herein is not particularly limited as long as it can react with an epoxy resin to form a 3-dimensional network structure, and examples thereof include an amide-based curing agent such as dicyandiamide and aliphatic polyamide, an amine-based curing agent such as diaminodiphenylmethane, m-phenylenediamine, ammonia, triethylamine and diethylamine, a phenol-based curing agent such as bisphenol a, bisphenol F, phenol novolac resin, cresol novolac resin and p-xylene novolac resin, and an acid anhydride-based curing agent, and a latent curing agent. These may be used alone, or in combination of 2 or more. For example: AB-HGA aqueous epoxy resin curing agent or Corning 751 aqueous epoxy resin curing agent.

For example, as the dispersing agent, nonionic surfactants such as polyoxyethylene isodecyl ether, polyoxyethylene lauryl ether, polyoxyethylene β naphthyl ether, polyoxyethylene styryl phenyl ether, and polyoxyethylene distyryl phenyl ether, and anionic surfactants such as polyoxyethylene lauryl ether sulfate, polyoxyethylene β naphthyl ether sulfate, polyoxyethylene styryl phenyl ether phosphate, polyoxyethylene distyryl phenyl carboxylate, lauryl ether phosphate, octyl ether carboxylate, distyryl phenyl ether sulfate, styryl phenyl ether phosphate, and β naphthyl ether carboxylate may be used.

The corrosion inhibitor of the above components is formulated into the coating to minimize corrosion of the substrate to which it is applied. Suitable corrosion inhibitors may be selected from organic pigments, inorganic pigments, organometallic pigments or other organic compounds that are insoluble in the aqueous phase. Anti-corrosive pigments such as phosphate or borate containing pigments, metal pigments and metal oxide pigments such as, but not limited to, zinc phosphate, zinc borate, silicic acid or silicates, e.g. calcium silicate or strontium silicate, and aminoanthraquinone based organic pigment corrosion inhibitors may also be concomitantly used. In addition, inorganic corrosion inhibitors, such as salts of nitroisophthalic acid, tannic acid, phosphoric acid esters, substituted benzotriazoles or substituted phenols, may be used, as may corrosion inhibitors, such as dicyclohexylamine nitrite, dicyclohexylamine phosphate, methyl phosphonate and the like.

The penetrant is small-molecular nano penetrant such as penetrant BX, penetrant T or penetrant JFC, and has strong penetrability. The super-strong permeability of the product is from a nano-small molecular structure of a penetrant, so that the product has super-strong permeability, namely a rust layer or an old paint film.

The active solvent plays a role of a solvent when the coating is prepared, and can react during the curing process after the coating is coated, and the epoxy resin is enhanced, hardened and modified. Active solvents that can be used in this embodiment are notably acetone, tetrahydrofuran, methyl ethyl ketone, dimethylformamide, dimethylacetamide, tetramethylurea, dimethyl sulfoxide, trimethyl phosphate, N-methyl-2-pyrrolidone.

Many conventional coalescents increase flow, reduce foam, and sometimes increase freeze/thaw stability while assisting in coalescence of the applied coating (which promotes the formation of a more continuous coating). Some coalescents are: lactate esters, 2-butoxyethanol, phthalate esters, 2- (2-butoxyethoxy) ethanol, methylphenylcarbinol, ethylene glycol, diethylene glycol, diacetone alcohol, propylene glycol, mono-and diesters of ethylene or propylene glycol, and the like.

The base layer protective agent has dual functions of crystallization and corrosion inhibition, can be well combined with a rust layer and an old paint layer for crystallization, and simultaneously, the super-strong function of the corrosion inhibitor prevents a base material from being rusted continuously.

The preparation of the components can adopt the following method, according to the formula, crystalline resin liquid and epoxy resin are added into a reaction kettle, heated and stirred, dispersant, penetrant, corrosion inhibitor, film forming auxiliary agent and active solvent are added, polymerization reaction is carried out, the temperature and the time are controlled, and finally the polymerization reaction is finished. When in use, the reactant is mixed with the curing agent.

The product can be used for rusted steel surfaces which are not cleaned by sand blasting due to environmental or safety factor limitations. The product has ultra-strong permeability and can strengthen the rust layer of the substrate. The adhesive force of the coating is improved and ensured by permeating and sealing gaps, joints, splicing parts and the old coating of the structural member, and the service life of the maintenance system is prolonged. The product can also be used for sealing aged rusted zinc surface for recoating. Meanwhile, the method is also effective in permeating, reinforcing and sealing the surfaces of concrete and masonry in all industrial environments.

Intermediate layer protecting agent:

the middle layer protective agent is applied to the base layer, is a high-performance, double-component and chemically-cured high-performance middle layer protective agent, and comprises the following components in parts by weight: 25-30% of coupling agent modified coating resin liquid, 25-30% of epoxy resin, 15-30% of curing agent, 1-2% of dispersing agent, 2-5% of penetrating agent, 9-25% of film forming additive, 4-20% of active solvent and 2-8% of second coupling agent.

The coating resin liquid modified by the coupling agent can link the base layer protective agent and the surface layer protective agent and can coat the base layer resin. The resin herein may refer to a resin solution modified by copolymerization of at least one coupling agent (e.g., titanate coupling agent) with at least one other monomer; the use of organometallic compounds as coupling agents has been developed from organochromium complexes to silane-based coupling agents. And then to a titanate coupling agent. The long carbon chain fatty acid group, the phosphate group, the pyrophosphate group and the like, wherein the isopropoxy group in the molecular formula can be coupled with the surface hydroxyl or proton of the inorganic pigment and the filler through chemical reaction to form the surface of the pigment and the filler. The long carbon chain hydrophobic group in the molecular formula can be physically or chemically combined with a high molecular base material, the interface state between an inorganic substance and an organic substance is effectively changed, the dispersibility and the anti-settling property of the inorganic substance in an organic system are provided, the reaction and fusion time can be shortened, the dispersibility and the utilization rate of a medium are improved, the viscosity of the system can be greatly reduced, the melt fluidity is increased, the process is improved, the using amount of a solvent is reduced, the combination amount of solid particles such as an original matrix corrosion product or an original coating residue is increased, and the mechanical property and the color degree of a protective layer are improved. The titanate coupling agent can tightly connect the inorganic matrix product and the organic polymer material, and fully play the role of each titanate molecule. Generally, only 0.4 percent of titanate coupling agent is needed for coating, so that the viscosity of the system can be obviously reduced, and the coating amount of the organic old coating of the inorganic substance of the matrix can be increased. The chelating titanate coupling agent has good performance. (di-zinc pyrophosphate), which may also be quaternized with alkanolamines or amines and dissolved in water to coat the inorganic base product and the old coating.

The other monomer is not limited to any particular one as long as it is copolymerizable with the coupling agent, and a monomer mixture of an ethylenically unsaturated monomer having one or more carboxyl groups (hereinafter referred to as a carboxyl group-containing unsaturated monomer) and another copolymerizable ethylenically unsaturated monomer (hereinafter referred to as another unsaturated monomer) is particularly preferable.

Examples of the above-mentioned carboxyl group-containing unsaturated monomer include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, α -chloroacrylic acid, ethacrylic acid and cinnamic acid, unsaturated dicarboxylic acids (anhydrides) such as maleic acid, maleic anhydride, fumaric acid, itaconic anhydride, citraconic acid and citraconic anhydride, and unsaturated polyvalent carboxylic acids (anhydrides) having a valence of 3 or more.

Among them, acrylic acid and methacrylic acid are preferable. These carboxyl group-containing unsaturated monomers may be used singly or in admixture of plural kinds.

Examples of the other unsaturated monomers include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, N-propyl acrylate, N-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, N-butyl acrylate, N-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, second butyl acrylate, second butyl methacrylate, t-butyl acrylate, t-butyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, allyl acrylate, allyl methacrylate, benzyl acrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, triethylene glycol methacrylate (methacrylic acid), glycidyl acrylate, glycidyl methacrylate, glycidyl acrylate, glycidyl methacrylate, glycidyl acrylate, glycidyl methacrylate, glycidyl acrylate, glycidyl methacrylate, vinyl methacrylate, glycidyl methacrylate, vinyl methacrylate, glycidyl methacrylate, vinyl methacrylate, glycidyl.

Among them, methyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, benzyl acrylate and benzyl methacrylate are preferred. The other unsaturated monomers mentioned above may be used alone or in combination of two or more.

The solvent used in the production of the coupling agent-modified coating resin solution of the present invention is generally (poly) alkylene glycol monoalkyl ethers such as ethylene glycol methyl ether, ethylene glycol ethyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol n-propyl ether, diethylene glycol n-butyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, propylene glycol methyl ether, propylene glycol ethyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol n-propyl ether, dipropylene glycol n-butyl ether, tripropylene glycol methyl ether (tripropylene glycol monomethylether), tripropylene glycol ethyl ether (tripropylene glycol monomethylethers), etc.; (poly) alkylene glycol monoalkyl ether acetates such as ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, and propylene glycol ethyl ether acetate; other ethers such as diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, and tetrahydrofuran; ketones such as methyl ethyl ketone, cyclohexanone, 2-heptanone, and 3-heptanone; alkyl lactates such as methyl 2-hydroxypropionate and ethyl 2-hydroxypropionate; methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl glycolate, methyl 2-hydroxy-3-methylbutyrate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, ethyl acetate, n-butyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl acetate, isoamyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, n-butyl butyrate, methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, ethyl ethoxypropionate, methyl 2-hydroxy-3-methylbutyrate, ethyl 3-methyl-3-methoxybutyl acetate, 3-methyl, Other esters such as methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxybutyrate; aromatic hydrocarbons such as toluene and xylene; and carboxylic acid amides such as N-methylpyrrolidone, N-dimethylformamide and N, N-dimethylacetamide. These solvents may be used alone or in combination of 2 or more.

The first coupling agent and other monomers are polymerized under the action of a catalyst and an initiator, and after the reaction is finished, the first coupling agent and other monomers are mixed with a defoaming agent, a neutralizing agent and deionized water to prepare an emulsion, preferably by using a phase inversion emulsification method. First, a small amount of water is added to the oil (organic solvent containing resin) to which the emulsifier is added, and mixed, whereby a W/O type emulsion can be obtained. Then, water was slowly added thereto to cause phase inversion, thereby obtaining an O/W type emulsion. As the means for mixing, there may be mentioned a shaft type stirrer and homogenizer with a rotary blade, a homomixer, a colloid mill and the like. The emulsification temperature is preferably in the range of 10 to 80 ℃ and more preferably in the range of 20 to 30 ℃. The average particle size of the emulsion is not particularly limited, but is usually about 0.01 to 10 μm, preferably about 0.1 to 1 μm. When the average particle diameter exceeds 10 μm, sedimentation is likely to occur, resulting in poor stability. In the following examples, coupling agent modified coating resin solutions were prepared as follows: adding 500g of deionized water, 50g of acrylic acid, 30g of methacrylic acid and 85g of 40% sodium hydroxide into a 1000ml four-neck flask with a stirring device, a nitrogen introducing device, a heating device and a temperature control device, uniformly stirring, adding 20g of sodium chloride, 95g of sodium sulfate, 10g of a stabilizer, 50g of isopropanol and 25g of 0.01N disodium ethylene diamine tetraacetate salt solution after adding 85g of 40% sodium hydroxide for neutralization, stirring for dissolution, introducing N₂Deoxidizing and heating to10g of 0.5% ammonium persulfate solution and 10g of 0.5% sodium bisulfite were added at 70 ℃ and stirred to react for about 3 hours, 10g of 0.5% azobisisobutylamidine hydrochloride solution was added, and the reaction was continued for 16 hours. The product was a white emulsion.

As the polymerization initiator, conventionally known polymerization initiators can be used without limitation, and examples thereof include cyclohexanone peroxide, 3, 5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, 1-bis (t-butylperoxy) -3,3, 5-trimethylcyclohexane, 1-bis (t-butylperoxy) cyclohexane, n-butyl-4, 4-bis (t-butylperoxy) valerate, cumene hydroperoxide, 2, 5-dimethylhexane-2, 5-dihydroperoxide, 1, 3-bis (t-butylperoxy-m-isopropyl) benzene, 2, 5-dimethyl-2, 5-di (t-butylperoxy) hexane, diisopropylbenzene peroxide, t-butylcumylperoxide, decanoyl peroxide, and the like, Peroxide polymerization initiators such as lauroyl peroxide, benzoyl peroxide, 2, 4-dichlorobenzoyl peroxide, di-t-amyl peroxide, bis (t-butylcyclohexyl) peroxydicarbonate, t-butylperoxybenzoate, 2, 5-dimethyl-2, 5-di (benzoylperoxy) hexane, and t-butylperoxy-2-ethylhexanoate; 2,2 '-azobis (isobutyronitrile), 2' -azobis-2-methylbutyronitrile, 1 '-azobis (cyclohexane-1-carbonitrile), azocumene, 2' -azobis (2-methylbutyronitrile), 2 '-azobis-2, 4-dimethylvaleronitrile, 4, 4' -azobis (4-cyanovaleric acid), 2- (tert-butylazo) -2-cyanopropane, 2 '-azobis (2,4, 4-trimethylpentane), 2' -azobis (2-methylpropane), 2 '-azobis [ 2-methyl-N- (2-hydroxyethyl) -propionamide ], dimethyl 2, 2' -azobis (2-methylpropionate), Azo polymerization initiators such as 1,1 ' -azobis (1-cyclohexane-1-carbonitrile), 2 ' -azobis [2- (2-imidazolin-2-yl) propane ], dimethyl-2, 2 ' -azobisisobutyrate and the like.

The neutralizing agent is not particularly limited as long as it is a neutralizing agent capable of neutralizing a carboxyl group, and examples thereof include sodium hydroxide, potassium hydroxide, trimethylamine, dimethylaminoethanol, 2-methyl-2-amino-1-propanol, triethylamine and ammonia.

The defoaming agent used in the emulsion polymerization is not particularly limited, and examples thereof include anionic emulsifiers such as sodium dialkylsulfosuccinate, sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium polyoxyethylene alkylphenyl ether sulfate and sodium alkyldiphenylether disulfonate, nonionic emulsifiers such as polyoxyethylene higher alcohol ether and polyoxyethylene alkylphenyl ether, and anionic or cationic reactive emulsifiers having a radical polymerizable double bond.

The reactive emulsifier is an emulsifier having a polymerizable unsaturated group and at least one group selected from a nonionic group, an anionic group and a cationic group in a molecule, and specific examples of the polymerizable unsaturated group include a (meth) allyl group, a (meth) acryloyl group, a propenyl group and a butenyl group.

After the coating resin liquid modified by the coupling agent is prepared into emulsion, it is preferable to add a reactive additive such as dihydroxyalkylamine (e.g., N-dihydroxyethylaniline) and polihexanediol to improve the protective effect of the protective layer.

The epoxy resin, curing agent, dispersant, penetrant, film-forming aid, active solvent and the like in the above components are the same as those in the description of the base layer protecting agent.

The active solvent is particularly preferably modified m-dihexanol, triethanolamine, 3-dimethyl-4, 4-diaminodicyclohexylmethane, or the like.

As the coupling agent used herein, a silane coupling agent such as KH550, KH570 or the like, or a titanate coupling agent or the like can be used.

The product is used for connecting the permeable base coat and the surface coat, increases the adhesive force with the permeable base coat, increases the matching property with the surface coat, and increases the matte effect of the surface coat.

Surface layer protective agent:

the protective agent for the surface layer of the industrial legacy steel structure is a high-performance single-component modified long-acting anti-corrosion surface layer protective agent, and is suitable for the durability protection of indoor and outdoor steel structures.

Comprises the following components in percentage by weight: 27-41% of plastic resin liquid, 15-25% of dispersing agent, 4-18% of penetrating agent, 5-10% of anti-ultraviolet aging agent, 13-30% of film-forming assistant and 9-35% of active solvent.

Examples of the thermoplastic resin include thermosetting resins such as polycarbonate resins, acrylic resins, polyester resins, epoxy resins, phenol resins, urea resins, fluororesins, polyester-urethane curable resins, epoxy-polyester curable resins, acrylic-polyester resins, acrylic-urethane curable resins, acrylic-melamine curable resins, and polyester-melamine curable resins; thermoplastic resins such as polyethylene resin, polypropylene resin, petroleum resin, thermoplastic polyester resin, and thermoplastic fluororesin. Under preferable conditions, acrylic-modified polyethylene terephthalate, polymethylene diisocyanate, and the like can be used. The following examples use acrylic acid modified polyethylene terephthalate, the preparation method of which is as follows: 20g of methacrylic acid, 120g of bis-hydroxyethyl terephthalate oligomer (BHET) and 500g of ethylene glycol were uniformly mixed in 2g of a catalyst Sb₂O₃Carrying out polymerization reaction under the action of (1), heating to 255 ℃, reacting for 4 hours, cooling and filtering to obtain the acrylic acid modified polyethylene terephthalate.

The types of the dispersing agent, the penetrating agent, the film forming auxiliary agent and the active solvent can be selected to be the same as those of the base layer and the middle layer protective agent.

Examples of the ultraviolet light aging agent include salicylic acid-based ultraviolet light absorbers, benzophenone-based ultraviolet light absorbers, benzotriazole-based ultraviolet light absorbers, cyanoacrylate-based ultraviolet light absorbers, triazine-based ultraviolet light absorbers, and benzoxazinone-based ultraviolet light absorbers. Among them, triazine-based ultraviolet absorbers and benzoxazinone-based ultraviolet absorbers are preferable from the viewpoint of dispersibility. Further, as the ultraviolet absorber, it is preferable to use a polymer having an ultraviolet absorbing group in a molecular chain. By using the polymer having an ultraviolet absorbing group in the molecular chain, deterioration of the ultraviolet absorbing function due to bleeding of the ultraviolet absorber or the like can be prevented. Examples of the ultraviolet absorbing group include a benzotriazole group, a benzophenone group, a cyanoacrylate group, a triazine group, a salicylic acid group, and a benzylidene malonate group. Among them, benzotriazolyl, benzophenone, and triazine are particularly preferable.

The agent has good weather resistance, sun resistance, water resistance and excellent matting property. After the application, the protective performance is high, and the light-reflecting and dazzling-free paint is not reflected. The product is used for protecting and developing industrial sites and protecting steel surfaces. The adhesive force of the guaranteed coating is improved and the service life of the maintenance system is prolonged by permeating, sealing and fixing gaps, joints, splicing parts and stress changes caused by the old rust layer and the old coating.

The long-acting comprehensive protection method for the industrial heritage steel structure based on the protective agent comprises the following steps:

firstly, the surface of the existing industrial heritage steel structure to be protected can only be subjected to simple slight treatment for removing surface dirt, and if the surface of the steel structure can be lightly brushed by using an artificial steel wire and a copper wire brush. The whole piece of the rust and the paint skin is removed.

And secondly, preparing the protective agent for the steel structure base layer of the industrial heritage according to the proportion, spraying the protective agent for the base layer to the surface needing protection, and allowing the protective agent to permeate, react and solidify for more than 36 hours. And (4) detecting the surface penetration degree, and testing the chemical reaction and the adhesive force of the solid, wherein the dryness meets the requirements of the protective agent. The following process may be performed, otherwise, step 1 is to be performed again.

And thirdly, processing the intermediate layer connecting agent of the steel structure of the industrial heritage on the basis of finishing the second step by checking, ensuring the reaction time of more than 24 hours by referring to the method in the previous step, and continuing to perform after checking the processing effect.

And fourthly, treating the protective agent of the surface layer of the industrial heritage steel structure on the basis of treating the connecting agent of the intermediate layer of the industrial heritage steel structure, wherein the first treatment and the second treatment of the protective agent are carried out at an interval of 12-24 hours, the treatment cannot be carried out in rainy and snowy weather, and the external temperature is above 5 ℃. Construction is carried out carefully in the weather of strong wind and sand reduction.

And after the industrial site steel structure treated according to the method is comprehensively detected, putting the industrial site steel structure into use.

EXAMPLE 1 preparation of base protective layer

The following raw materials are selected according to the weight percentage:

crystalline resin solution 10% (acrylic acid modified polypropylene crystalline resin emulsion)

28% epoxy resin (bisphenol A type)

Curing agent 14% (dicyandiamide curing agent)

Dispersant 4% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 5% (penetrant JFC)

Corrosion inhibitor 7% (dicyclohexylamine phosphate)

Film-forming assistant 9% (phthalate)

Active solvent 23% (trimethyl phosphate)

The preparation method comprises the following steps: reaction charging sequence: adding crystalline resin liquid and epoxy resin into a jacketed reaction kettle, slowly heating and stirring at 50-80 revolutions per minute, starting to heat at a heating rate of 50 ℃/h, adding a dispersing agent, a penetrating agent, a corrosion inhibitor, a film forming auxiliary agent and an active nano solvent when the temperature reaches 100 ℃, carrying out polymerization reaction for 3 hours, and finally finishing the polymerization reaction.

EXAMPLE 2 preparation of base protective layer

The following raw materials are selected according to the weight percentage:

crystalline resin liquid 6% (acrylic acid modified polypropylene crystalline resin emulsion)

28% epoxy resin (bisphenol F type)

Curing agent 14% (dicyandiamide curing agent)

Dispersant 5% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 7% (penetrant T)

Corrosion inhibitor 7% (dicyclohexylamine phosphate)

Film-forming assistant 9% (diacetone alcohol)

Active solvent 24% (methyl ethyl ketone and trimethyl phosphate mixed according to 1: 3 volume ratio)

EXAMPLE 3 preparation of base protective layer

The following raw materials are selected according to the weight percentage:

crystalline resin liquid 9% (acrylic acid modified polypropylene crystalline resin emulsion)

Epoxy resin 25% (phenol novolac type)

Curing agent 15% (diethylamine curing agent)

Dispersant 5% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 8% (penetrant JFC)

Corrosion inhibitor 8% (methyl phosphonate)

Film-forming assistant 6% (ethylene glycol)

Active solvent 24% (mixture of acetone and trimethyl phosphate in 1: 2 volume ratio)

EXAMPLE 4 preparation of base protective layer

The following raw materials are selected according to the weight percentage:

Epoxy resin 24% (phenol novolac type)

Curing agent 15% (diethylamine curing agent)

Dispersant 5% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 8% (penetrant JFC)

Corrosion inhibitor 8% (methyl phosphonate)

Film-forming assistant 6% (ethylene glycol)

Active solvent 24% (mixture of acetone and trimethyl phosphate in 1: 3 volume ratio)

Comparative example 1

The difference from example 1 is that: in the preparation process of the adopted acrylic acid modified polypropylene crystalline resin emulsion, acrylic acid monomer N-hydroxymethyl acrylamide is not added for modification.

Comparative example 2

The difference from example 1 is that: no penetrant was added.

Base layer protective layer Performance test

Carrying out St2 grade surface treatment on a rusted steel plate, painting the paint, and detecting the thickness according to GB/T13452.2-2008; the drying time of the paint film is measured according to GB/T1728-1979 (1989); the adhesion is detected according to GB/5210-85 (pull open method); the gloss is measured according to GB/T9754-1988; salt spray resistance was determined according to GB/T1771-1991.

As can be seen from the table, the base protective layer provided by the invention has better adhesion and salt spray resistance, and particularly, as can be seen from example 1 compared with comparative example 1, after the acrylic acid modified polypropylene crystalline resin emulsion is adopted, the surface dryness, the solid dryness, the adhesion and the salt spray resistance of the retention layer can be obviously improved; compared with the comparative example 2, the example 1 shows that after the penetrant is added, the protective layer can be effectively compatible with the base material, the adhesive force and the salt fog resistance are improved, and the long-term protective effect on industrial heritage can be improved.

EXAMPLE 5 preparation of intermediate protective layer

The following raw materials are selected according to the weight percentage:

coupling agent modified coating resin solution 26% (prepared as described above)

Epoxy resin 27% (bisphenol F type)

Curing agent 16% (dicyandiamide curing agent)

Dispersant 1% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 3% (penetrant T)

Film-forming assistant 12% (diacetone alcohol)

Active solvent 7% (methyl ethyl ketone and trimethyl phosphate mixed according to 1: 3 volume ratio)

Coupling agent 8% (KH550)

Reaction charging sequence: and adding a coupling agent modified coating resin liquid, epoxy resin and a dispersing agent into a jacket reaction kettle, slowly heating, stirring at 80 revolutions per minute, adding the dispersing agent, heating to 90 ℃ at the temperature rise speed of 80 ℃ per hour, adding a penetrating agent, a film-forming assistant, an active solvent and the coupling agent, controlling the temperature and the time for 2 hours, and reacting to finally finish the reaction.

EXAMPLE 6 preparation of intermediate protective layer

The following raw materials are selected according to the weight percentage:

28% epoxy resin (bisphenol F type)

Curing agent 15% (dicyandiamide curing agent)

Dispersant 2% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 2% (penetrant T)

Film-forming assistant 14% (diacetone alcohol)

Active solvent 7% (trimethyl phosphate)

Coupling agent 6% (KH550)

EXAMPLE 7 preparation of intermediate protective layer

The following raw materials are selected according to the weight percentage:

26% of the coupling agent-modified coating resin solution (the difference from example 5 is that after the preparation of the resin emulsion is completed,

to this was also added N, N-dihydroxyethylaniline in an amount of 5% by weight of the emulsion

Epoxy resin 27% (bisphenol F type)

Curing agent 16% (dicyandiamide curing agent)

Dispersant 1% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 3% (penetrant T)

Film-forming assistant 12% (diacetone alcohol)

Coupling agent 8% (KH550)

Comparative example 3

The difference from example 5 is that: the coating resin liquid which is not modified by adding the coupling agent is not modified by the coupling agent (titanate coupling agent is not added in the preparation process).

Comparative example 4

The difference from example 5 is that: no penetrant was added.

The protective layers of examples 5 to 7 and comparative examples 3 to 4 were sprayed on the surface of the base protective layer of example 1, and the performance test data were as follows:

wherein, the thickness is detected according to GB/T13452.2-2008; the drying time of the paint film is measured according to GB/T1728-1979 (1989); the adhesion is detected according to GB/5210-85 (pull open method); the gloss is measured according to GB/T9754-1988; the artificial aging resistance is detected according to GB/T23987-2009; salt spray resistance was determined according to GB/T1771-1991. As can be seen from the table, the middle protective layer provided by the invention has good adhesive force, drying speed and salt spray resistance and aging resistance after acting on the base protective layer; compared with the example, the example 7 shows that the coupling agent modified coating resin liquid modified by the dihydroxyalkylamine can improve the salt spray aging resistance of the middle layer and enhance the protection effect of the protective layer; compared with the comparative example 3, the embodiment 5 can show that the adhesive force and the salt spray resistance and the aging resistance of the protective layer can be effectively improved by adopting the coupling agent modified coating resin liquid; compared with the comparative example 4, the example 5 shows that the adhesion between the intermediate layer and the base layer can be effectively promoted by adding the penetrant, the salt spray resistance is improved, and the long-term protection effect on industrial heritage can be improved.

EXAMPLE 8 preparation of Top-coat protectant

The following raw materials are selected according to the weight percentage:

30% of plastic resin (the acrylic modified polyethylene terephthalate mentioned above)

Dispersant 16% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 11% (penetrant JFC)

Anti-ultraviolet aging agent 9% (triazine ultraviolet absorbent)

Film-forming assistant 14% (diacetone alcohol)

Active solvent 20% (trimethyl phosphate)

Reaction charging sequence: slowly heating the mixture by a jacket reaction kettle, adding plastic resin liquid, a dispersing agent, a penetrating agent and an active solvent, stirring at 60 revolutions per minute, adding the dispersing agent, heating to 85 ℃ at the heating rate of 50 ℃ per hour, adding the penetrating agent, a film-forming assistant and an anti-ultraviolet aging agent, controlling the temperature to be 100 ℃ and the time to be 4 hours, and finally finishing the reaction.

EXAMPLE 9 preparation of Top-coat protectant

The following raw materials are selected according to the weight percentage:

plastic resin liquid 37% (the above-mentioned acrylic acid modified polyethylene terephthalate)

Dispersant 15% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 5% (penetrant T)

Anti-ultraviolet aging agent 9% (cyanoacrylate ultraviolet absorbent)

Film-forming assistant 17% (2-butoxyethanol)

Active solvent 17% (methyl ethyl ketone and trimethyl phosphate mixed according to 1: 3 volume ratio)

Example 10

The following raw materials are selected according to the weight percentage:

plastic resin liquid 34% (the above-mentioned acrylic acid modified polyethylene terephthalate)

Dispersant 16% (polyoxyethylene β naphthyl ether sulfate)

Penetrant 11% (penetrant JFC)

Anti-ultraviolet aging agent 5% (triazine ultraviolet absorbent)

Film-forming assistant 18% (phthalate)

Active solvent 16% (trimethyl phosphate)

Comparative example 5

The difference from example 8 is that: the polyethylene terephthalate of the plastic resin liquid was not subjected to acrylic modification (methacrylic acid was not added in the preparation).

Comparative example 6

The difference from example 8 is that: no penetrant was added.

The surface protective layers of examples 8 to 10 and comparative examples 5 to 6 were sprayed on the surface of the intermediate layer of example 5, and the performance test data:

wherein, the thickness is detected according to GB/T13452.2-2008; the drying time of the paint film is measured according to GB/T1728-1979 (1989); the adhesion is detected according to GB/5210-85 (pull open method); the gloss is measured according to GB/T9754-1988; the artificial aging resistance is detected according to GB/T23987-2009; salt spray resistance was determined according to GB/T1771-1991. As can be seen from the table, the surface protective layer provided by the invention has better adhesion with the intermediate layer, and has better salt spray resistance and aging resistance; example 8 compared to comparative example 5, the adhesion to the interlayer and the salt spray resistance can be effectively improved by using the acrylic-modified polyethylene terephthalate; compared with the comparative example 6, the total thickness of the coating and the salt spray resistance and aging resistance of the coating can be effectively improved by adding the penetrant in the example 8, and the long-term protection effect on industrial heritage can be improved.

The invention also provides a long-acting comprehensive protection method for an industrial legacy steel structure, which respectively adopts the base layer, the middle layer and the surface layer protective agent coating, and comprises the following steps:

Claims

1. The application of the surface layer protective agent in the surface protection of industrial heritage is characterized in that the surface layer protective agent comprises the following components in percentage by weight: 27-41% of plastic resin liquid, 15-25% of dispersing agent, 4-18% of penetrating agent, 5-10% of anti-ultraviolet aging agent, 13-30% of film-forming assistant and 9-35% of active solvent; the penetrating agent is penetrating agent BX, penetrating agent T or penetrating agent JFC; the plastic resin liquid is acrylic modified polyethylene terephthalate, and the preparation method of the acrylic modified polyethylene terephthalate comprises the following steps: 20g of methacrylic acid, 120g of bishydroxyethyl terephthalate oligomer and 500g of ethylene glycol were mixed uniformly in the presence of 2g of Sb catalyst₂O₃Carrying out polymerization reaction under the action of (1), heating to 255 ℃, reacting for 4 hours, cooling and filtering to obtain acrylic acid modified polyethylene terephthalate; the anti-ultraviolet aging agent is selected from salicylate ultraviolet absorbent, benzophenone ultraviolet absorbent, benzotriazole ultraviolet absorbent, cyanoacrylate ultraviolet absorbent, triazine ultraviolet absorbent or benzoxazinone ultraviolet absorbent; the film-forming assistant is selected from 2-butoxyethanol, phthalate, ethylene glycol, diethylene glycol, diacetone alcohol or propylene glycol; the active solvent is selected from acetone, tetrahydrofuran, methyl ethyl ketone, dimethylformamide, dimethylacetamide, tetramethylurea, dimethyl sulfoxide, trimethyl phosphate or N-methyl-2-pyrrolidone;

in the application, the method also comprises the following steps: spraying a surface layer protective agent on the surface of the middle layer;

the intermediate layer is obtained by spraying an intermediate layer connecting agent;

the middle layer connecting agent comprises, by weight, 25-30% of a coupling agent modified coating resin liquid, 25-30% of bisphenol F epoxy resin, 15-30% of a dicyandiamide curing agent, 1-2% of polyoxyethylene β naphthyl ether sulfate, 2-5% of a penetrating agent, 9-25% of diacetone alcohol, 4-20% of an active solvent and 2-8% of a silane coupling agent, and the preparation method of the coupling agent modified coating resin liquid comprises the following steps:adding 500g of deionized water, 50g of acrylic acid, 30g of methacrylic acid and 85g of 40% sodium hydroxide into a 1000ml four-neck flask with a stirring device, a nitrogen introducing device, a heating device and a temperature control device, uniformly stirring, adding 20g of sodium chloride, 95g of sodium sulfate, 10g of a stabilizer, 50g of isopropanol and 25g of 0.01N disodium ethylene diamine tetraacetate salt solution after adding 85g of 40% sodium hydroxide for neutralization, stirring for dissolution, introducing N₂And (3) deoxidizing, heating to 70 ℃, adding 10g of 0.5% ammonium persulfate solution and 10g of 0.5% sodium bisulfite, stirring and reacting for about 3 hours, adding 10g of 0.5% azobisisobutylamidine hydrochloride solution, and continuing to react for 16 hours.