JP6222869B1 - Solvent-free liquid acrylic resin composition and method for producing solvent-free liquid acrylic resin composition - Google Patents

Abstract

[PROBLEMS] To provide excellent weatherability and adhesiveness, which is useful as a fixing material for gravel or aggregate, has an appropriate fluidity, and does not contain a volatile organic solvent. Providing a small amount of solvent-free liquid acrylic resin composition. An A component containing at least a (meth) acrylic acid alkyl ester monomer having no reactive functional group and not containing water or a volatile organic solvent as a solvent, and a hydrolyzable copolymerizable with the A component The component B which is a decomposable alkoxysilyl group-containing monomer is not copolymerizable with the component A in the presence of a chain transfer agent, has a boiling point of 150 ° C. or higher, and a viscosity at 25 ° C. of 50000 mPa · Including a reaction product obtained by copolymerization in a liquid compound (component C) that is s or less, and the total amount of component A and component B is 100 parts by weight, the amount of component C is 10 to 900 parts by weight. A solvent-free liquid acrylic resin composition having an R viscosity calculated by the viscosity × viscosity ratio of 100 mPa · s or more and less than 20000 mPa · s. [Selection figure] None

Description

  The present invention can be applied to paints and binders suitable for a wide range of uses such as construction-related uses and civil engineering-related uses, which are liquid and have good curability, despite having no water or organic solvent as a solvent. The present invention relates to a good solvent-free liquid acrylic resin composition and a method for producing a solvent-free liquid acrylic resin composition. More specifically, it exhibits room temperature moisture curable properties that are cured by chemical reaction with moisture in the air at room temperature, and can be made into a one-component or two-component room temperature moisture curable type that is superior in functionality, requiring (heating) drying. Solvent-free acrylic resin composition that has no odor problems due to solvent, does not whiten the formed film even if left in warm water for a long time, has excellent weather resistance, fluidity and adhesion It relates to technology that provides goods.

  In recent years, movements to reduce VOC (volatile organic compounds) from the viewpoints of environmental protection and safety are increasing, and paints and binders are also shifting from conventional solvent-based to water-based ones. . However, conventional water-based paints and water-based binders using water-based emulsions have insufficient film-forming properties and coating properties (water resistance, adhesion, blocking resistance, weather resistance), etc. compared to solvent systems, Since sufficient film performance cannot be obtained unless it is dried over time, it is not suitable for outdoor use. For this reason, solvent-based paints and binders are often used in consideration of weather resistance and the like when used outdoors such as in buildings and civil engineering-related applications.

  For paints and binders for outdoor use, coating performance (film formation, crosslinking process) in a short time at room temperature is required. For outdoor use, for example, in recent years, the importance of securing water permeability has been recognized again in parks, roads, parking lots, etc., and makeup gravel, natural stone, and artificial aggregate are used during construction. In addition, gravel is conventionally used on railway lines and tracks, and gravel is fixed using resin binders and adhesives prepared for outdoor use (patents) References 1 and 2). In the following, the use situation and problems will be described using effects on railway lines and tracks as representative examples.

  In general, on railroad tracks and tracks, concrete plates called track slabs are installed on the concrete roadbed, and the railroad slab track bed (hereinafter referred to as the slab trackbed) and crushed stone and gravel on the roadbed. There is a “ballast track bed” (hereinafter referred to as a ballast track bed) having a structure in which sleepers are arranged on the upper part of a so-called ballast (gravel or aggregate) and rails are laid thereon. The ballast roadbed can efficiently disperse the load and vibration of the train transmitted to the sleepers and transmit it to the roadbed, so it has lower vibration and noise than the slab roadbed, and the train running on the ballast roadbed is comfortable to ride. It is also used on many routes because it has good drainage (drainage) such as rain and has low construction costs. On the other hand, the ballast roadbed is vibrated due to the frequency and load of the train passing, and the ballast itself is vibrated and worn by rubbing the ballasts. There is a risk that it will lead to the sinking of sleepers. Moreover, there is a problem that crushed stones and gravel with a small particle size may be scattered due to the passage of the vehicle, which is dangerous.

  As a method of preventing fluidization and sinking phenomenon and ballast scattering as described above, resin binders and adhesives are regularly sprayed and fixed on the ballast. Proposals have been made. For example, in Patent Document 3, a method of reinforcing a ballast road bed by injecting a two-component urethane adhesive composed of a main component composed of a terminal isocyanate group-containing urethane prepolymer and a curing agent as a ballast fixing agent and curing the adhesive. Proposals have been made. In Patent Document 4, an epoxy resin composition comprising an epoxy oligomer and an amine compound containing a plurality of primary or (and) secondary amines in one molecule is dispersed and solidified from the upper part of the ballast. Proposals have been made on methods for stabilizing ballast ballasts that fix ballasts.

  As a method of fixing ballast that is actually performed, for example, a method of applying a net for preventing scattering having a mesh of an appropriate size on the ballast roadbed itself, a rubber latex, a synthetic resin emulsion, a mortar, etc. Examples thereof include a method for fixing ballast and a method for spraying a one-component moisture-curable urethane resin to fix the ballast. Among these, moisture-curing urethane resins are fast and excellent in workability, and can be cured at room temperature for several hours when used at midnight after the last train. It is adopted in.

  Speaking of a moisture-curable resin composition, for example, Patent Document 5 discloses a moisture-curable coating agent based on an aprotic solvent, which contains at least a binder having an alkoxysilyl group and a crosslinking catalyst. Proposals have been made.

JP 2008-266886 A JP 2008-31781 A JP 2002-38401 A JP 2005-307585 A Special table 2012-522850 gazette

  However, as described below, there are various problems in the above-described conventional technology, and development of a more optimal resin composition for fixing crushed stones and gravel (ballast) is required. First, the urethane resins of Patent Documents 3 and 4 have good film-forming properties and water resistance, but contain volatile organic solvents (toluene, xylene, etc.), so that the body for workers and local residents can be used. There are concerns about environmental impacts such as air pollution caused by volatilization of organic solvents during drying, and ignition of volatilized organic solvents. Further, since the weather resistance of the resin is limited, even if the ballast is hardened with the resin, it is necessary to replace it at intervals of several years. Here, since the conventionally used urethane resin has low weather resistance compared to other resins, it is necessary to perform maintenance in a shorter period of time, and there is a problem that much labor and cost are required. The technique of Patent Document 5 includes a binder having an alkoxysilyl group, which is a so-called silicone resin, and the silicone resin is more expensive than other resins. On the other hand, there is a practical problem to be solved that it is difficult to use widely.

  In view of the above, development of an emulsion-based adhesive that does not use a volatile organic solvent and has little influence on the environment and that has excellent film-forming properties, weather resistance, and the like is desired. However, many emulsion-based adhesives are obtained by emulsion polymerization and have poor drying properties. For example, even if an adhesive having excellent film-forming properties, weather resistance, etc. is obtained, it is not suitable for ballast fixing. There is no proposal for practical use. From the above, although it is inexpensive and economical, it can form a coating film with excellent adhesiveness and transparency as needed, for example, fixing ballast that requires regular maintenance Even when used for the above, development of a solvent-free resin composition that exhibits excellent weather resistance and does not use a volatile solvent and that is easy to work and environmentally friendly is demanded.

  Therefore, in view of the above reasons, the object of the present invention is useful for outdoor paints and binders corresponding to a wide range of applications such as construction-related applications and civil engineering-related applications. For example, a resin for fixing ballast on a ballast roadbed When applied as a composition, it has a fluidity that can be applied and applied, as well as excellent weather resistance and adhesion, and if necessary, can form a film with excellent transparency. Because it does not contain a solvent, it is an economical, solvent-free, liquid, moderately fluid resin composition that is excellent in workability, has little environmental impact, and can reduce the frequency of maintenance compared to conventional products. It is to provide. An object of the present invention is, for example, water-free and volatile organic solvents that do not contain solvents and liquids that do not contain solvents and can be substituted for silicone resins and urethane resins that are widely used for fixing ballast (gravel or aggregate). An object of the present invention is to provide a novel acrylic resin composition having an appropriate fluidity.

The above object is achieved by the present invention described below. That is, the present invention is a solvent-free liquid acrylic resin composition that does not contain water and a volatile organic solvent as a solvent, and is a copolymerizable (meth) acrylic acid alkyl ester having no reactive functional group. In the presence of a chain transfer agent (D component), the A component containing at least the monomer (a1) and the B component which is a hydrolyzable alkoxysilyl group-containing monomer copolymerizable with the A component A reaction product obtained by copolymerization in a liquid compound (component C) having a boiling point of 150 ° C. or higher and a viscosity at 25 ° C. of 50000 mPa · s or less, which has no copolymerizability with the component, When the total amount of the component B and the component B is 100 parts on a mass basis, the amount of the component C is 10 to 900 parts on a mass basis, and the R viscosity shown in the following formula (1) is 100 mPa・ S or more, 20000mP · Provides a good solventless liquid acrylic resin composition fluidity and less than s.
R viscosity = viscosity (mPa · s / 25 ° C.) × viscosity ratio (1)
However, the viscosity ratio = (Viscosity at the lowest rotation of the B-type viscometer / Viscosity at the highest rotation of the B-type viscometer)

  The following are mentioned as a preferable form of the above-mentioned solvent-free liquid acrylic resin composition of this invention. The component C contains at least a hydrolyzable alkoxysilyl group-containing liquid compound; the component A may be a monomer having a reactive functional group copolymerizable with the component (a1) ( a2) (excluding those having a hydrolyzable alkoxysilyl group); when the total amount of the component A and the component B is 100 parts by mass, the component A is based on mass In the range of 50 parts or more and 99 parts or less, and the B component is in the range of 1 part or more and 50 parts or less on a mass basis; Or a two-component moisture-curing type; for fixing gravel or aggregate.

As another embodiment, the present invention provides an A component containing at least a copolymerizable (meth) acrylic acid alkyl ester monomer (a1) having no reactive functional group as a monomer component, At least a B component which is a hydrolyzable alkoxysilyl group-containing monomer copolymerizable with the component, and the monomer component is copolymerizable with the A component in the presence of a chain transfer agent (D component). A reaction step of copolymerizing in a liquid compound (component C) having a boiling point of 150 ° C. or higher and a viscosity at 25 ° C. of 50000 mPa · s or less, and the amount of the C component in the reaction step However, when the total amount of the A component and the B component is 100 parts by mass, it is 10 to 900 parts by mass, and the following formula of the reaction product obtained by copolymerization in the reaction step: The R viscosity shown in (1) is 10 mPa · s or more, to provide a method of manufacturing a good solventless liquid acrylic resin composition fluidity and less than 20000 mPa · s.
R viscosity = viscosity (mPa · s / 25 ° C.) × viscosity ratio (1)
However, the viscosity ratio = (Viscosity at the lowest rotation of the B-type viscometer / Viscosity at the highest rotation of the B-type viscometer)

  The following are mentioned as a preferable form of the manufacturing method of the above-mentioned solvent-free liquid acrylic resin composition of this invention. As the component C, a hydrolyzable alkoxysilyl group-containing liquid compound is used; the reaction step is performed in two stages, and in the first stage, a part of the component A and a part of the component B are used in a single amount. As a body component, a liquid acrylic resin was obtained by copolymerization reaction in the liquid compound (C component) in the presence of the chain transfer agent (D component), and obtained in the second step and the first step. For example, a copolymerization reaction may be performed by adding the remainder of the component A and the remainder of the component B (but not adding the component D) as a monomer component to a reaction system containing a liquid acrylic resin.

  According to the present invention, it is a liquid resin that does not contain water or an organic solvent and exhibits high fluidity while being highly solid, and can be applied to paints and binders for construction-related applications and civil engineering-related applications. It can be replaced with urethane resin and silicone resin widely used for fixing ballast (gravel or aggregate), has room temperature curing that does not require heating and drying for film formation, has no problem of odor due to solvent, and warm water Even if left for a long time, the formed film does not whiten, it has excellent water whitening resistance, excellent weather resistance, and if necessary, it can form a film with excellent transparency, and it has appropriate fluidity. In addition, a solventless liquid acrylic resin composition having good adhesion is provided. Moreover, according to the preferable form of this invention, the solvent (curing accelerator) is contained, and the one-component type or two-component room temperature moisture-curing solventless liquid acrylic resin composition which is excellent in various functions described above. Things can also be provided.

  Next, the present invention will be described in more detail with reference to preferred embodiments for carrying out the invention. The term “(meth) acryl” in the claims and the specification of the present invention means both “acryl” and “methacryl”, and the term “(meth) acrylate” "And" methacrylate ".

  The present inventors have paid attention to an acrylic resin that can be provided at a low cost and has a weather resistance superior to that of a urethane resin, and for example, functions useful as a resin composition for fixing ballast (gravel or aggregate). As a result of intensive studies to develop a product capable of expressing the present invention, the present invention has been completed. Specifically, the present inventors can copolymerize (meth) having at least a reactive functional group in a specific liquid compound (C component) in the presence of a chain transfer agent (D component). By copolymerizing an acrylic acid alkyl ester monomer (component A) and a hydrolyzable alkoxysilyl group-containing monomer (component B) copolymerizable with the component A, a volatile organic solvent or water The liquid acrylic resin composition which does not use this was obtained, and it discovered that this composition had the following outstanding characteristic. Specifically, it has room temperature curability, there is no problem of odor due to solvent, the formed film does not whiten even if left in warm water for a long time, it has excellent water whitening resistance, excellent weather resistance, and fluidity The present invention has been found to have desirable performance that can be applied to paints and binders for construction-related and civil engineering-related uses, which have good properties and adhesiveness. That is, in the present invention, it is possible to provide a novel solvent-free and liquid acrylic resin composition that can be used as a paint or binder with excellent functionality, can be used in a wide range of outdoor applications, and is excellent in environmental applicability and economy. Provided is a technology for combining an acrylic resin and a silicone resin.

  As described above, in the present invention, as the monomer component, the A component containing at least a copolymerizable (meth) acrylic ester monomer having no reactive functional group, and the copolymerizable with the A component An alkoxysilyl group was introduced into the structure, which is a reaction product obtained by polymerizing a hydrolyzable alkoxysilyl group-containing monomer B component in a specific liquid compound (C component). It stipulates that it is a solvent-free liquid acrylic resin composition containing a copolymer. That is, a specific copolymer (reactant) characterizing the present invention is produced by a process (production method) in which two specific monomers are used as raw materials and reacted under specific conditions. Here, it is a well-known fact in the art that the polymer is an aggregate (mixture) of various polymer molecules having different molecular weights. The acrylic resin introduced with the alkoxysilyl group described above is not only the molecular weight due to the difference in the structure of the monomer used, the blending ratio of the monomers, the blending ratio of the resin as an intermediate and the above-mentioned specific compound, etc. It becomes a complex assembly of various polymer molecules with different molecular structures. It is impossible and directly impractical to identify the structure of individual polymer molecules contained in such a complex assembly (mixture), and the identification is a process (production process) for obtaining a polymer. ) For the first time. In the present invention, a copolymerization reaction is performed in a specific liquid compound (C component) in the presence of a chain transfer agent (D component) in order to obtain a final solvent-free liquid acrylic resin composition. However, this point can be specified only by the process (production method). From these impossible / unpractical circumstances, in the present invention, the solvent-free liquid acrylic resin composition is specified by a process (production method) for obtaining the resin.

  The solvent-free liquid acrylic resin composition of the present invention is characterized in that it polymerizes in a specific liquid compound (C component) described later in the presence of a chain transfer agent (D component). It exists in the liquid compound which is C component, and does not contain water and a volatile organic solvent as a solvent. In the present invention, this is expressed as “solvent-free liquid”.

≪Solvent-free liquid acrylic resin composition≫
The solvent-free liquid acrylic resin composition of the present invention does not contain water and a volatile organic solvent, and contains at least a copolymerizable (meth) acrylic acid alkyl ester monomer (a1) having no reactive functional group. A component containing A and a B component which is a hydrolyzable alkoxysilyl group-containing monomer copolymerizable with the A component, in the presence of a chain transfer agent (D component), have copolymerizability with the A component. A reaction product obtained by polymerization in a liquid compound (component C) having a boiling point of 150 ° C. or higher and a viscosity at 25 ° C. of 50000 mPa · s or less, and the total amount of the component A and the component B is mass When the amount is 100 parts on the basis, the amount of the C component is 5 to 900 parts on a mass basis, and the R viscosity at 25 ° C. is 100 mPa · s or more and less than 20000 mPa · s. . Hereinafter, each configuration will be described in more detail. In addition, the said R viscosity is a value shown to following formula (1). The viscosity ratio in the formula (1) means (the viscosity of the B-type viscometer minimum rotation / the viscosity of the B-type viscometer maximum rotation).
R viscosity = viscosity (mPa · s / 25 ° C.) × viscosity ratio (1)

[Component A]
<(A1)>
The solventless liquid acrylic resin composition of the present invention is a copolymerizable (meth) acrylic acid alkyl ester monomer (a1) having no reactive functional group (hereinafter referred to simply as “(a1)”). And an acrylic resin obtained by copolymerizing a hydrolyzable alkoxysilyl group-containing monomer (B component) that can be copolymerized with the A component described later. It is characterized by. Moreover, the usage-amount of A component containing said (a1) is in the range of 50 parts or more and 99 parts or less on a mass basis, when the total amount of B component and A component mentioned later is 100 parts on a mass basis. Preferably there is.

The (a1) is not particularly limited, and a conventionally known (meth) acrylic acid alkyl ester monomer can be used. More specifically, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, (meth) Isobutyl acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-heptyl (meth) acrylate, (meth) N-octyl acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, (meth) acrylate, phenyl (meth) toluyl acrylate, (meth) acrylate, benzyl (main ) Trifluoromethylmethyl acrylate, 2-trifluoromethylethyl (meth) acrylate, 2-perfluoroethylethyl (meth) acrylate, 2-perfluoroethyl-2-perfluorobutylethyl (meth) acrylate, (Meth) acrylic acid 2-perfluoroethyl, (meth) acrylic acid perfluoromethyl, (meth) acrylic acid diperfluoromethyl methyl, (meth) acrylic acid 2-perfluoromethyl-2-perfluoroethyl ethyl, ( Examples thereof include 2-perfluorohexylethyl (meth) acrylate, 2-perfluorodecylethyl (meth) acrylate, 2-perfluorohexadecylethyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.

<(A2)>
In the present invention, in addition to the above-mentioned (a1), the component A has a reactive functional group that can be copolymerized with the above-mentioned (a1) within a range not contrary to the intended purpose of the present invention. Other monomers (a2) (except for those having a hydrolyzable alkoxysilyl group) (hereinafter sometimes simply referred to as “(a2)”) may be used. . The (a2) used as needed is not particularly limited as long as it can be copolymerized with the (a1), and the following can be used. For example, unsaturated group-containing compounds such as styrene, α-methylstyrene, vinyl toluene, (meth) acrylonitrile, vinyl acetate, vinyl propionate, butadiene, isoprene, and / or (meth) acrylic acid, vinyl sulfonate, croton Examples thereof include ethylenically unsaturated acids such as acid, maleic acid and itaconic acid and / or anhydrides thereof. These may be used alone or in combination of two or more. As described above, as (a2), those having a reactive functional group such as a sulfone group or a carboxy group can also be used. In addition to (a1), (a2) such as (meth) acrylic acid and vinyl sulfonate in the above is used in combination with (a1) as a monomer for obtaining the reactant defined in the present invention. Has a structure in which a sulfone group or a carboxy group is introduced into the skeleton. The inventor has a structure in which these groups are appropriately introduced into the skeleton of the acrylic resin so that the same function as the catalyst (curing accelerator) described later can be exhibited. It is considered that the solvent-free liquid acrylic resin composition of the present invention can be made into a one-component type or two-component type room temperature moisture curable type that is more excellent in functionality without further adding.

  The amount of (a2) that can be copolymerized with the aforementioned main component (a1) in the component A is the amount of the chain transfer agent (component D) in the specific liquid compound (component C) described later. In the presence, the R viscosity at 25 ° C. in the solventless liquid acrylic resin composition of the present invention finally obtained by copolymerizing (a1) and (a2) with the component B described later is 100 mPa as defined in the present invention. -It should just be in the range used as s or more and less than 20000 mPa * s. For example, when (a2) has a reactive functional group such as a sulfone group or a carboxy group, if the amount used is excessive and the reactive functional group occupies the total amount of the A component, the A component and the B component Are copolymerized in the C component, these reactive functional groups react with the liquid compound as the C component, resulting in gelation of the polymer, and the R viscosity at 25 ° C. is defined in the present invention. Since a solvent-free liquid acrylic resin composition within the range cannot be obtained, it must be avoided.

[Component B: Hydrolyzable alkoxysilyl group-containing monomer copolymerizable with component A]
In the present invention, a hydrolyzable alkoxysilyl group-containing monomer copolymerizable with the A component is used as the B component together with the A component, and these monomer components are copolymerized under specific conditions. Thus, an acrylic resin having an alkoxysilyl group is obtained as a reaction product, and a solvent-free liquid acrylic resin composition is formed using the reaction product as a main component.

  As the hydrolyzable alkoxysilyl group-containing monomer that can be copolymerized with the component A, which is the component B, conventionally known monomers can be used as long as they have a hydrolyzable alkoxysilyl group. For example, the following can be used. Vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) Acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxypropylmethyldiethoxysilane, 4-vinylphenyltrimethoxysilane, 3- (4-vinylphenyl) propyltrimethoxysilane, 4-vinylphenylmethyltrimethoxysilane, etc. Is mentioned. Preferably, the following can be used. For example, 3-methacryloxypropyltrimethoxysilane [KBM-503 (trade name), manufactured by Shin-Etsu Chemical Co., Ltd.], 3-methacryloxypropylmethyldimethoxysilane [KBM-502 (product) Name), manufactured by Shin-Etsu Chemical Co., Ltd.]. These may be used alone or in combination of two or more.

  As the use amount of the B component, the total amount of the A component and the B component can be used in an amount of 1 to 50 parts with respect to 100 parts on a mass basis, but from the viewpoint of providing an inexpensive product, 1 to The proportion is preferably within the range of 30 parts. According to the study by the present inventors, a copolymer capable of realizing the remarkable effects of the present invention can be obtained even when the amount of the B component used is in the range of 1 to 20 parts. When the proportion of the B component is less than 1 part, the proportion of the alkoxysilyl group present in the acrylic resin as the main component is too small, and in particular, a one-component or two-component room temperature moisture curable type is used. In some cases, sufficient performance may not be exhibited. On the other hand, when the proportion of the B component exceeds 50 parts, the proportion of the A component is relatively too small, so that embrittlement progresses and sufficient film performance may not be obtained. Absent.

[C component: specific liquid compound]
In the present invention, the A component and the B component as described above are not copolymerized with the A component in the presence of a chain transfer agent (D component) described later, the boiling point is 150 ° C. or higher, and 25 ° C. And a reaction product obtained by copolymerization in a liquid compound having a viscosity of 50000 mPa · s or less (hereinafter sometimes simply referred to as “C component”). According to the study by the present inventors, the above-described A component and B component are used as monomer components in a specific liquid compound (C component) as described above in the presence of a chain transfer agent (D component). It is possible to obtain a liquid acrylic resin composition without solvent and containing no water and volatile organic solvent.

  Suitable examples of the component C include hydrolyzable compounds as shown in the following general formula 1, which contain a hydrolyzable alkoxysilyl group in at least one of the backbones such as the main chain, side chain, and terminal. Examples include alkoxysilyl group-containing liquid polysiloxanes and hydrolyzable alkoxysilyl group-containing liquid oligomers as shown in the following general formula 2. The “liquid compound” defined in the present invention is a concept including any of these.

（一般式１中、Ｘは、メチル基、フェニル基、反応性官能基のいずれかであり、ＳｉＯＲは、アルコキシシリル基を示す。）

（一般式２中、Ｍｅはメチル基であり、ＳｉＯＲは、アルコキシシリル基を示す。）

(In General Formula 1, X is any one of a methyl group, a phenyl group, and a reactive functional group, and SiOR represents an alkoxysilyl group.)

(In general formula 2, Me is a methyl group, and SiOR represents an alkoxysilyl group.)

  The component C constituting the present invention preferably contains “a hydrolyzable alkoxysilyl group in at least one of the backbones such as the main chain, side chain, and terminal” as described above. However, the component C constituting the present invention has, as its basic aptitude, “a liquid compound having no copolymerization with the component A, having a boiling point of 150 ° C. or more and a viscosity at 25 ° C. of 50000 mPa · s or less”. There is no particular limitation as long as it satisfies the requirements. For this reason, the following can also be used suitably. For example, phenylpropylene glycol, phenyl glycol, texanol, phenyl diglycol, terpineol, dihydroterpineol, dihydroterpinel acetate, ethylene glycol, 1,4-butanediol, diethylene glycol, polyethylene glycol, 1,3-butylene glycol, dipropylene Liquid compounds such as glycol, polypropylene glycol, octanediol, 2,4-diethyl-1,5-pentanediol, diethylene glycol monobutyl ether and butyl carbitol acetate, or silicone oils that do not contain hydrolyzable alkoxysilyl groups Any of which can be used. The following are mentioned as a commercial item which can be used as C component by this invention.

  Examples of commercially available polypropylene glycol-based liquid compounds include D-2000 [trade name, manufactured by NOF Corporation, molecular weight 2000, viscosity 270 mPa · s / 25 ° C. (measured value), boiling point 150 ° C. or higher (measured value). ], D-4000 [trade name, manufactured by NOF Corporation, molecular weight 4000, viscosity 850 mPa · s / 25 ° C. (measured value), boiling point 150 ° C. or higher (measured value)], and the like.

  Examples of commercially available hydrolyzable alkoxysilyl group-containing liquid polysiloxanes suitable as the component C constituting the present invention include KR-510 [trade name, manufactured by Shin-Etsu Chemical Co., Ltd., methyl / phenyl group]. Containing silicone oligomer, viscosity = 100 mPa · s / 25 ° C., boiling point = 150 ° C. or higher (measured value)] and the like.

  Examples of commercially available hydrolyzable alkoxysilyl group-containing liquid polyether compounds suitable as the component C constituting the present invention include SAT010 [trade name, manufactured by Kaneka Corporation, terminal silicone-modified polyether resin, Viscosity 640 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)] or SAX115 [trade name, manufactured by Kaneka Corporation, terminal silicone-modified polyether resin, viscosity 25000 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value) )], SAT200 [trade name, manufactured by Kaneka Corporation, terminal silicone-modified polyether resin, viscosity 640 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)], SAX 220 [trade name, manufactured by Kaneka Corporation, terminal silicone Modified polyether resin, viscosity 46000 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)], AT350 [trade name, manufactured by Kaneka Corporation, terminal silicone-modified polyether resin, viscosity 6000 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)], SAT400 [trade name, manufactured by Kaneka Corporation, terminal silicone-modified polyether resin , Viscosity 24,000 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)]. Each of the products listed above has a viscosity at 25 ° C. of 50000 mPa · s or less. Moreover, when the present inventors confirmed the boiling point, all were 150 degreeC or more.

  The amount of the C component used in the present invention is required to be 10 to 900 parts when the total amount of the A component and the B component, which are raw material monomers, is 100 parts on a mass basis. According to the study by the present inventors, when the amount of the C component is less than 10 parts, the viscosity of the polymerized acrylic resin liquid becomes high, the fluidity is lost, and gelation easily occurs, which is not preferable. Further, the progress of the polymerization is impaired, the polymerization rate is lowered, and the monomer may remain. In this case, the odor of the monomer remains, which causes a problem that it is difficult to produce a product. It will be. On the other hand, when the amount of component C exceeds 900 parts, the proportion of the acrylic resin in the composition decreases, and it takes time to form a coating film, and sufficient coating film performance cannot be obtained. That is, by appropriately designing the amount of component C used, in the solvent-free liquid acrylic resin composition of the present invention, the specific copolymerization reaction product (acrylic resin) defined in the present invention is at least on a mass basis. It may be configured to be contained at a high solid content of 10% or more, preferably 25% or more, more preferably 50% or more. Specifically, the amount of component C is preferably 10 to 300 parts, more preferably 10 to 100 parts, based on mass. The solvent-free liquid acrylic resin composition of the present invention comprising a reaction product obtained by copolymerizing the A component and the B component in the C component in the above ratio in the presence of a chain transfer agent (D component) described later is: Since the polymerization proceeds sufficiently, the problem of odor does not occur, and the formed coating film has excellent weather resistance.

  The liquid compound which is the above-described component C has a considerable influence on the physical properties of the solvent-free liquid acrylic resin composition of the present invention depending on the type thereof, and therefore, it is preferable to select the liquid compound as appropriate in accordance with its use and specifications. For example, in the liquid oligomer in which hydrolyzable alkoxysilyl groups are introduced at both ends as shown in the general formula 2, the distance between the crosslinking points differs depending on the type, and is longer than that having a short distance. A film having a distance between cross-linking points is more flexible. Here, when the ballast is used for fixing the ballast of the ballast track, as described above, a material having excellent flexibility is preferable for the purpose of preventing vibration due to passage of a train and wear due to load. Therefore, when the solvent-free liquid acrylic resin composition of the present invention is applied, the C component defined in the present invention has a long distance between cross-linking points as shown in the above general formula 2, and a linear chain. It is preferable to use a typical liquid compound.

  On the other hand, as the component C used for copolymerization, the solvent-free liquid acrylic of the present invention having a structure having a plurality of crosslinking points at the terminal and side chain as shown in the general formula 1 is used. When the resin composition is applied to a paint or a binder, a hard film can be obtained. Therefore, what is necessary is just to select suitably the liquid compound which is C component according to the use. Moreover, in addition to the kind of liquid compound which is a C component, it is an acrylic monomer which is an A component to be copolymerized in the C component, or a B component for the purpose of containing a hydrolyzable alkoxysilyl group in the acrylic resin. Since the hardness and flexibility of the film to be formed can be freely adjusted by appropriately adjusting the type and blending ratio of the monomers, according to the present invention, the film can be formed with optimal characteristics according to various applications. It is possible to provide a solventless liquid acrylic resin composition that can be used.

  It does not specifically limit as a method to perform copolymerization in C component, What is necessary is just to carry out by the method as listed below. For example, by adding the A component and the B component to the C component and heating and stirring in a nitrogen atmosphere in the presence of a chain transfer agent (D component) as described later, the A component and the B component are put in separate containers in advance. Examples of the method include polymerization after adding the mixture to the C component heated in a nitrogen atmosphere in the presence of a chain transfer agent (D component).

[D component: chain transfer agent]
A reaction product obtained by copolymerizing the component A and the component B constituting the solvent-free liquid acrylic resin composition of the present invention is a product obtained by copolymerization in the component C described above in the presence of a chain transfer agent (component D). It is necessary to be. That is, by copolymerizing raw materials such as (meth) acrylic acid alkyl ester monomers using a chain transfer agent, the degree of polymerization of the resulting acrylic resin can be appropriately adjusted, and is defined in the present invention. Thus, it is possible to obtain an acrylic resin composition having an appropriate fluidity while maintaining a liquid state with an appropriate viscosity.

  The chain transfer agent used in this case is not particularly limited. For example, n-dodecyl mercaptan (lauryl mercaptan), 2,4-diphenyl-4-methyl-1-pentene, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol , 2-ethylhexyl thioglycolate and 2,3-dimercapto-1-propanol. Among these, lauryl mercaptan (L-SH) is preferable. The amount of these chain transfer agents used is preferably about 0.1 to 5.0 parts by mass per 100 parts by mass of the total of component A and component B.

[E component: polymerization initiator]
Moreover, it is preferable that the reaction product formed by copolymerizing the A component and the B component constituting the present invention is polymerized using a polymerization initiator (E component). Examples of the polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), and 2,2′-azobis (2,4-dimethyl-4). Azo compounds such as (-methoxyvaleronitrile), and the like. Among them, 2,2′-azobisisobutyronitrile (AIBN) is preferable. An organic peroxide polymerization initiator can also be used. For example, 4-dichlorobenzoyl peroxide, t-butylperoxypivalate, o-methylbenzoyl peroxide, bis-3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, t-butylperoxy-2 Organics such as ethyl hexanoate, cyclohexanone peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, dicumyl peroxide, lauroyl peroxide, diisopropylbenzene hydroperoxide, t-butyl hydroperoxide and di-t-butyl peroxide Peroxides can be used.

  The amount of the polymerization initiator used is preferably about 0.1 to 5.0 parts on a mass basis per 100 parts in total of component A and component B. The polymerization initiator can be used in each stage of polymerization, and a predetermined amount can be added in each stage to cause a polymerization reaction. Note that the organic peroxide polymerization initiator is easy to graft, and in some cases may be gelled during the polymerization, so care must be taken in its use.

[Physical properties of solvent-free liquid acrylic resin composition]
The reaction product (acrylic resin) obtained by copolymerizing the component A and the component B constituting the solvent-free liquid acrylic resin composition of the present invention obtained as described above has a weight average molecular weight of, for example, 5,000 to 500,000. If it is a grade, it is more preferable that it is about 10,000 to 100,000.

  The solvent-free liquid acrylic resin composition of the present invention is required to have an R viscosity at 25 ° C. specified in the present invention in the range of 100 mPa · s or more and less than 20000 mPa · s. Furthermore, it is preferable that R viscosity in 25 degreeC is about 100-10000 mPa * s. Such a solvent-free liquid acrylic resin composition having an R viscosity has good fluidity and particularly good coating properties even though it is solvent-free. For this reason, for example, it can be used favorably for ballast fixation.

  The above R viscosity at 25 ° C. is preferably the viscosity when the proportion (solid content) of the acrylic resin in the solvent-free liquid acrylic resin composition of the present invention is in the range of 20 to 60%. Moreover, you may adjust by adding C component described previously by mixing | blending so that the ratio for an acrylic resin may become the said range. Another advantage of the present invention is that it can provide a solvent-free liquid acrylic resin composition having a high solid content as described above.

  Since the solventless liquid acrylic resin composition of the present invention does not contain a volatile organic solvent, it is environmentally friendly, and since the resin component is an acrylic resin, it is more weather resistant than urethane resins, epoxy resins, etc. Excellent and good adhesiveness can be formed, and if necessary, a film having excellent transparency can be formed. In addition, it is cheaper than silicone resins and urethane resins. The solvent-free liquid acrylic resin composition of the present invention can be suitably used as it is for adhesives and coating paints, but can be effectively used particularly for ballast fixing of the above-mentioned ballast track. .

≪Method for producing solvent-free liquid acrylic resin composition≫
The method for producing a solvent-free liquid acrylic resin composition of the present invention comprises at least a copolymerizable (meth) acrylic acid alkyl ester monomer (a1) having no reactive functional group as a monomer component. At least a component and a component B which is a hydrolyzable alkoxysilyl group-containing monomer copolymerizable with the component A, and the monomer component in the presence of a chain transfer agent (component D) Having a reaction step of copolymerizing in a liquid compound (component C) having a boiling point of 150 ° C. or higher and a viscosity at 25 ° C. of 50000 mPa · s or less, having no copolymerizability with the components, The amount of the C component was 10 to 900 parts on a mass basis when the total amount of the A component and the B component was 100 parts on a mass basis, and was obtained by copolymerization in the reaction step. In the following formula (1) of the reaction product The R viscosity, 100 mPa · s or more, and less than 20000 mPa · s.
R viscosity = viscosity (mPa · s / 25 ° C.) × viscosity ratio (1)
However, the viscosity ratio = (Viscosity at the lowest rotation of the B-type viscometer / Viscosity at the highest rotation of the B-type viscometer)

  The A component, the B component, the C component, and the D component used in the method for producing the solventless liquid acrylic resin composition of the present invention are the same as described above. As a preferred configuration in the production method of the present invention, the reaction step can be performed in two stages. Specifically, in the first stage, the A component and the B component are used as monomer components, and a copolymerization reaction is performed in the liquid compound (C component) in the presence of the chain transfer agent (D component). A transparent liquid acrylic resin having good compatibility is obtained, and in the second stage, the liquid acrylic resin obtained in the first stage is made to function as a dispersing agent in the reaction system. As components, A component and B component are added dropwise (but not D component) and copolymerized. Thus, in the reaction system at the second stage, it is preferable to perform a copolymerization reaction of a higher degree of polymerization than the acrylic resin at the first stage by removing the D component.

  By making the said reaction process the structure which performs in two steps, the following effect is acquired in the manufactured solvent-free liquid acrylic resin composition. For example, like Example 7 mentioned later, depending on the kind of A component and B component to be used, the viscosity of the obtained solvent-free liquid acrylic resin composition may become high, and the fluidity | liquidity may be inferior. If the fluidity is inferior, when the solventless liquid acrylic resin composition of the present invention is used as a paint, the surface of pebbles or the like may not be coated in a good state, and depending on the application, it may be formed. It was necessary to increase the strength of the film. In such a case, as in Example 9 to be described later, the copolymerization reaction step is performed in two stages, and a low-polymerization type liquid acrylic resin is obtained in the first stage. It is preferable to polymerize the liquid acrylic resin to obtain a dispersion type solventless liquid acrylic resin composition which is cloudy. Furthermore, in the composition of the component A used in the second-stage reaction process, when polymerized with respect to the component C to be used, 50% or more of a monomer having an acrylic resin composition inferior in dissolving power is included. The configuration is particularly effective. Examples of the monomer having an acrylic resin composition that is inferior in dissolving power when polymerized with respect to the component C used at this time include MMA (methyl methacrylate), EMA (ethyl methacrylate), AN (acrylonitrile), MAN, and the like. (Methacrylonitrile) and the like.

  As described above, a dispersion-type liquid acrylic resin can be obtained by performing the reaction step in two steps as described above. The dispersion-type liquid acrylic resin thus obtained has an advantage that the viscosity can be easily adjusted so as to exhibit good fluidity. In addition, as described above, a monomer capable of forming a harder film in the A component used in the second stage copolymerization reaction process than the A component used in the first stage copolymerization reaction process. If the components are appropriately used, a dispersion-type liquid acrylic resin capable of forming a film having a desired strength can be obtained. Further, by increasing the degree of polymerization in the second stage copolymerization reaction step, a solventless liquid acrylic resin composition capable of forming a tougher film can also be obtained as appropriate.

≪Catalyst (curing accelerator) ≫
The solventless liquid acrylic resin composition of the present invention is a one-component or two-component room temperature moisture curable type that is more excellent in functionality by further comprising a mixture containing a catalyst (curing accelerator). be able to. By setting it as such a form, it becomes a more suitable thing for normal temperature moisture hardening type aggregate fixation. That is, the presence of the catalyst (curing accelerator) allows the alkoxysilyl group in the component B constituting the solvent-free liquid acrylic resin composition of the present invention to be more easily hydrolyzed by moisture in the air, It is considered that the hydrolyzed silanol group is condensed so that it can be cured more easily even at room temperature. For this reason, even when the component C constituting the solvent-free liquid acrylic resin composition of the present invention is a hydrolyzable alkoxysilyl group-containing liquid oligomer, the presence of a catalyst (curing accelerator) Since the hydrolyzable alkoxysilyl group is hydrolyzed more easily by moisture in the air, a one-component or two-component room-temperature moisture-curing type with better functionality can be obtained.

  As the curing accelerator used above, conventionally known metal organic carboxylates such as tin, titanium, zirconium, iron, antimony, manganese, alkoxides; organic titanates, organic titanium chelate compounds, amine compounds, etc. Is mentioned. More specifically, tin compounds such as dibutyltin dilaurate, dibutyltin dioctoate, dioctyltin dilaurate, dibutyltin malate ester, dimethyltin dineodecanoate, dibutyltin dimethoxide, dioctyltin dineodecanoate; tetrabutyl Titanium compounds such as titanate, tertiary-amyl titanate, diisopropoxybis (acetylacetonate) titanium, diisopropoxybis (ethylacetoacetate) titanium, dibutylamine, laurylamine, tetramethylguanidine, tetramethylguanidylpropyltri Examples thereof include amine compounds such as methoxysilane and salts thereof. More preferably, a metal chelate compound curing accelerator may be used. The addition amount is 0.001 to 5 parts, more preferably 0.1 to 2 parts, with respect to 100 parts of the liquid acrylic resin composition. These can be used alone or in combination of two or more. The curing accelerator may be used as a so-called two-component type, which is blended immediately before using the solventless liquid acrylic resin composition of the present invention, or blended in advance in the solventless liquid acrylic resin composition of the present invention. It may be used as a so-called one-component type.

  The pot life and curing speed of the paint using the solvent-free liquid acrylic resin composition of the present invention are optimal for various applications by changing the kind and addition amount of the curing accelerator as appropriate. Can be designed into things.

  By adopting the above-described configuration, a solvent-free liquid acrylic resin composition suitable for use in paints (coating paints), binder-related uses, and for fixing aggregates, which mainly had problems in the drying process for outdoor use, is provided. Is done. That is, in the case of an aqueous system, sufficient film performance cannot be obtained unless the film is dried over time. On the other hand, the organic solvent system has problems such as odor, environmental impact, and flammability during drying. On the other hand, these problems can be solved by using the solventless liquid acrylic resin composition of the present invention. More specifically, the solvent-free liquid acrylic resin composition of the present invention is a liquid resin composition exhibiting room temperature moisture-curability that can be cured after several hours at room temperature without drying (heating). And excellent environmental adaptability. In particular, by including a catalyst (curing accelerator), when it is a one-component moisture-curing type, it cures at room temperature for several hours, and is therefore useful as a ballast fixing binder. For example, if it is used for roadbed repair and maintenance, it will harden at room temperature for several hours even if sprayed at the time of midnight roadbed repair after the last train, so there is no effect on the first operation, and the effect of maintenance work on operation Can be reduced.

  Next, the present invention will be described more specifically with reference to examples and comparative examples. In the text, “part” is based on mass.

Example 1
A 1 L 4-neck round bottom flask equipped with a stirrer, thermometer and reflux condenser was prepared. And the following A component, B component, C component, and D component were prepared to this flask, and the liquid acrylic resin of the present Example was obtained as follows. Specifically, first, 70 parts of butyl acrylate (abbreviated as BA, SP value = 9.0) and 25 parts of methyl methacrylate (abbreviated as MMA, SP value = 9.5) were used as the A component. 5 parts KBM-502 (trade name, 3-methacryloxypropylmethyldimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.) is used as the B component, and KR-510 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) is used as the C component. , 100 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)], 2 parts of lauryl mercaptan (abbreviated as L-SH) as a chain transfer agent as component D, The mixture was stirred and mixed to prepare a monomer solution. Then, the monomer solution prepared above was heated to 80 ° C. and bubbled with nitrogen gas for 30 minutes with stirring to remove dissolved oxygen in the solution. Then, while maintaining the internal temperature at 80 ° C., 2 parts of 2,2′-azobisisobutyronitrile (abbreviated as AIBN) is added as a polymerization initiator of the E component, and the reaction of the A component and the B component is started. In the presence of a chain transfer agent, a copolymerization reaction between the A component and the B component was performed in the C component, and the reaction was completed after 8 hours. Then, it filtered for the purpose of removing an aggregate, and obtained the liquid acrylic resin composition-1 of a present Example. The viscosity of the obtained liquid acrylic resin composition-1 was 2500 (mPa · s / 25 ° C.).

<Evaluation>
Using the liquid acrylic resin composition-1 obtained above, a coating material as an evaluation sample was prepared by the following method, and using this coating material, room temperature moisture-curing property, water whitening resistance, adhesiveness, fluidity, and odor Each was evaluated. The evaluation results are summarized in Table 1-1.

1. Room temperature moisture curable Evaluation with 100 parts of liquid acrylic resin composition-1 containing 1.0 part of curing accelerator (diisopropoxybis (ethylacetoacetate) titanium) and containing catalyst (curing accelerator) A paint was prepared. Next, this evaluation coating was applied on a glass substrate so that the coating thickness was 100 μm, left at room temperature (25 ° C.) for 3 hours, and the cured state of the coating film was observed. Evaluation was performed based on the criteria, and the results are shown in Table 1-1. In addition, (circle) was set as the pass and (triangle | delta) and x were evaluated as the failure.

(Evaluation criteria)
○: Lightly touch the center of the painted surface with a fingertip, and the fingertip is not soiled.
Δ: Lightly touching the center of the painted surface with a fingertip, and the fingertip is slightly dirty.
X: The center of the paint surface is lightly touched with a fingertip, and the fingertip is dirty and not cured.

2. Flowability Using each of the coating materials for evaluation used in the previous room temperature moisture-curing test, as a guideline for the flowability, the viscosity at 25 ° C. is measured with a B-type viscometer. Using the measured value and each measured value of the viscosity at the maximum rotation of the B-type viscometer, the R viscosity was calculated by the following formula (1). And it evaluated by the following four steps using the value of each obtained R viscosity, and the result was shown to Table 1-1. In addition, (double-circle), (circle), (triangle | delta) was set as the pass, and x was evaluated as failure.
R viscosity = viscosity (mPa · s / 25 ° C.) × viscosity ratio (1)
Viscosity = BH type viscometer, measured at 10 rpm, 25 ° C (mPa · s / 25 ° C)
Viscosity ratio = (B-type viscometer minimum rotation 2 rpm viscosity / B-type viscometer maximum rotation 20 rpm viscosity)

(Evaluation criteria)
A: R viscosity is 100 or more and less than 3500 (mPa · s).
○: R viscosity is 3500 or more and less than 10,000 (mPa · s).
(Triangle | delta): R viscosity is 10,000 or more and less than 20000 (mPa * s).
X: R viscosity is 20000 or more (mPa · s).

3. Water whitening resistance The evaluation paint used in the room temperature moisture curability test was applied at room temperature so that the coating thickness was 100 μm, and allowed to stand for 3 hours to form a film, which was used as an evaluation sample. And after leaving this sample in warm water of 60 ° C. for 24 hours, taking it out from warm water and immediately leaving it in room temperature water for 24 hours, then taking it out from water and drying at room temperature, visually observing the degree of whitening of the film. did. And it evaluated on the following references | standards and the result was shown to Table 1-1. In addition, (circle) was set as the pass and x was set as the disqualification.

(Evaluation criteria)
○: No whitening.
X: There is whitening.

4). Adhesiveness Each of the coating materials for evaluation used in the room temperature curing test was sprayed on pebbles (particle size 3 to 6 cm, about 100 g) and allowed to stand at room temperature for 3 hours to be coated. Coated pebbles samples for use. And adhesiveness was evaluated by the peeling condition when this coated pebbles sample was rubbed 10 times with a finger. Specifically, the evaluation was performed according to the following criteria, and the results are shown in Table 1-1. In addition, (double-circle), (circle), (triangle | delta) was set as the pass, and x was set as the disqualification.

(Evaluation criteria)
◎: No peeling ○: Less than 10% peeling △: Less than 30% peeling ×: 30% or more peeling

5. Odor The test paint prepared in the room temperature curing test was applied to a base film so that the coating thickness was 100 μm, and left at room temperature (25 ° C.) for 3 hours. Thereafter, the odor of the coating film was sniffed, the strength of the odor was confirmed and evaluated according to the following criteria, and the results are shown in Table 1-1. In addition, (circle) was set as the pass and x was set as the disqualification.
(Evaluation criteria)
○: There is no off-flavor odor in the coating film.
X: The coating film has a strange odor.

(Examples 2 to 8)
Liquid acrylic resin composition-2 to liquid acrylic resin in the same manner as in Example 1 except that the components and amounts used in Example 1-1 were changed to the types and amounts used in Table 1-1 and Table 1-2. Composition-8 was produced respectively. And in Table 1-1 and Table 1-2, similarly to the case of Example 1, the viscosity at 25 degreeC of each obtained liquid acrylic resin was shown. Moreover, about liquid acrylic resin composition-2-liquid acrylic resin composition-8, the same evaluation as having been performed with liquid acrylic resin composition-1 is performed, and in Table 1-1 and Table 1-2, the The results are summarized.

Example 9
As in Example 1, a 1 L four-necked round bottom flask equipped with a stirrer, a thermometer, and a reflux condenser was prepared as a reaction vessel. Using this vessel, as described below, the components A and B were mixed. Copolymerization was performed in two stages. First, the first-stage copolymerization reaction was performed using the A component, the B component, the C component, the D component, and the E component described in the left column of Example 9 in Table 1-2, and then in the reaction vessel. The second stage copolymerization reaction was performed using the A component, the B component, and the E component described in the right column of Example 9 in Table 1-2, and the cloudy liquid acrylic resin composition of this example was performed. Got.

  More specifically, in the first-stage copolymerization reaction, as component A, 27 parts of butyl acrylate (abbreviated as BA, SP value = 9.0) and ethyl acrylate (abbreviated as EA, SP value). = 9.5) Two types of 27 parts were used, and 6 parts of KBM-502 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) were used as the B component. And as C component, KR-510 [trade name, manufactured by Shin-Etsu Chemical Co., Ltd., viscosity 100 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)] and 50 parts SAT010 [trade name, manufactured by Kaneka Corporation, 50 parts of viscosity 640 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)] and 50 parts of SAX 220 [trade name, manufactured by Kaneka Corporation, viscosity 46000 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)] A mixture of three parts was used. In the first-stage copolymerization reaction, 2 parts of lauryl mercaptan (abbreviated as L-SH) is used as a chain transfer agent as the D component, and these components A, B, C and D are stirred and mixed. A monomer solution was prepared. Then, the monomer solution prepared above was heated to 80 ° C. and bubbled with nitrogen gas for 30 minutes with stirring to remove dissolved oxygen in the solution. While maintaining the internal temperature at 80 ° C., 1.6 parts of 2,2′-azobisisobutyronitrile (abbreviated as AIBN) is added as a polymerization initiator for the E component, and the monomer component A is added. Initiate the reaction of the component and the B component, and in the presence of the chain transfer agent that is the D component, the first stage copolymerization reaction of the A component and the B component is carried out in the C component for 4 hours. A composition was obtained.

  Next, in the second stage copolymerization reaction, 4 hours after the start of the first stage copolymerization reaction, the second stage copolymerization reaction using the A component and the B component as described below. Went. Specifically, while maintaining the internal temperature in the reaction vessel at 80 ° C., 0.4 part of AIBN was added as a polymerization initiator of the E component in the presence of the liquid acrylic resin obtained by the first stage polymerization, 36 parts of methyl methacrylate (abbreviated as MMA, SP value = 9.5) described in the right column of Example 9 in Table 1-2 and KBM-502 (trade name, Shin-Etsu) as B component 4 parts) (manufactured by Chemical Industry Co., Ltd.) was dropped over 2 hours. Then, a second-stage copolymerization reaction was performed, and the reaction was completed after 4 hours. Then, it filtered for the purpose of removing an aggregate, and obtained the liquid acrylic resin composition-9 which carried out the cloudiness dispersion of the present Example. The viscosity of the obtained cloudy liquid acrylic resin composition-9 was 4000 (mPa · s / 25 ° C.). Compared with the liquid acrylic resin composition obtained in Example 8, although the property was a cloudy liquid, an adhesive having a low viscosity and excellent adhesiveness was obtained. About the obtained cloudy liquid acrylic resin composition-9, evaluation similar to what was performed with the liquid acrylic resin composition-1 of Example 1 was performed, and the result was collectively shown in Table 1-2.

Details of the symbols of the components shown in Table 1 are as follows.
(A component)
● BA: butyl acrylate ● EA: ethyl acrylate ● MMA: methyl methacrylate ● MAAC: methacrylic acid

(B component)
● KBM-502 (trade name): 3-methacryloxypropylmethyldimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd. ● KBM-503 (product name): 3-methacryloxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd.

(C component)
● D-2000 (trade name): polypropylene glycol (molecular weight 2000), viscosity 270 mPa · s / 25 ° C. (measured value), boiling point 150 ° C. or higher (measured value), manufactured by NOF Corporation,
● KR-510 (trade name): methyl / phenyl group-containing silicone oligomer (viscosity 100 mPa · s / 25 ° C.), boiling point 150 ° C. or higher (measured value), manufactured by Shin-Etsu Chemical Co., Ltd. ● KF-414 (trade name): alkyl Modified silicone oil (no hydrolyzable alkoxysilyl group), viscosity 100 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value), manufactured by Shin-Etsu Chemical Co., Ltd. ● SAT010 (trade name): terminal silicone-modified polyether resin (viscosity 640 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value), manufactured by Kaneka Corporation • SAX115 (trade name): terminal silicone-modified polyether resin (viscosity 640 mPa · s / 25 ° C.), boiling point 150 ° C. or higher (measured value) ), Manufactured by Kaneka Corporation ● SAX220 (trade name): terminal silicone-modified polyether resin (viscosity 46000 mPa · s / 2) ° C), boiling point 150 ° C or higher (measured value), manufactured by Kaneka Corporation ● SAT 350 (trade name): terminal silicone-modified polyether resin (viscosity 6000 mPa · s / 25 ° C), boiling point 150 ° C or higher (measured value), manufactured by Kaneka Corporation ● SAT400 (trade name): terminal silicone-modified polyether resin (viscosity 24000 mPa · s / 25 ° C.), boiling point 150 ° C. or higher (measured value), manufactured by Kaneka Corporation

(D component)
● L-SH: Lauryl mercaptan (n-dodecyl mercaptan)

(E component)
AIBN: 2,2'-azobisisobutyronitrile

(Comparative example 1: B component is not used)
A 1 L four-necked round bottom flask equipped with a stirrer, thermometer and reflux condenser was prepared in the same manner as in the examples. And the following A component, C component, and D component were prepared to this flask, and the liquid acrylic resin of this comparative example was obtained as follows. Specifically, 80 parts of BA and 20 parts of MMA, which are the A component defined in the present invention, are used as the C component defined in the present invention, D-4000 [trade name, manufactured by NOF Corporation, viscosity 850 mPa · s / 25 ° C. (measured value), boiling point 150 ° C. or higher (measured value), polypropylene glycol having a molecular weight of 4000] as a D-component chain transfer agent, L-SH as 1 part, and other components, 100 parts of MA440 [trade name, manufactured by Kaneka Corporation, silicone-modified acrylic resin, viscosity: 75000 mPa · s / 25 ° C., boiling point: 150 ° C. or higher (measured value)] was added and mixed by stirring to prepare a monomer mixture. Then, the monomer solution prepared above was heated to 80 ° C. and bubbled with nitrogen gas for 30 minutes with stirring to remove dissolved oxygen in the solution. Then, while maintaining the internal temperature at 80 ° C., 1 part of AIBN is added as a polymerization initiator which is the E component, and the polymerization reaction of the A component is started. Copolymerization reaction of component A consisting of the above monomer was carried out, and the reaction was terminated after 8 hours. Then, it filtered for the purpose of removing an aggregate, and obtained the solventless liquid acrylic resin composition which does not have the hydrolyzable alkoxysilyl group derived from B component of this comparative example.

  The viscosity of the solventless liquid acrylic resin composition of the present comparative example obtained above was 85000 (mPa · s / 25 ° C.), was high in viscosity, and lacked fluidity. In addition, the solvent-free liquid acrylic resin composition of this comparative example was evaluated in the same manner as in the examples, and these results are shown in Table 2.

(Comparative Example 2: D component not used)
A 1 L four-necked round bottom flask equipped with a stirrer, thermometer and reflux condenser was prepared in the same manner as in the examples. And the following A component, B component, and C component were prepared to this flask, and the liquid acrylic resin of this comparative example was obtained as follows. Specifically, 50 parts of ethyl acrylate (abbreviated as EA), which is an A component specified in the present invention, 40 parts of MMA, 10 parts of KBM-503, which is a B component specified in the present invention, A monomer mixture was prepared by adding 100 parts of SAT010 (trade name: terminal silicone-modified polyether resin), which is a C component specified in the invention, and stirring and mixing. Then, the monomer solution prepared above was heated to 80 ° C. and bubbled with nitrogen gas for 30 minutes with stirring to remove dissolved oxygen in the solution. Then, while maintaining the internal temperature at 80 ° C., 2 parts of benzoyl peroxide (BPO) is added as a polymerization initiator which is the E component to start the polymerization reaction. A copolymerization reaction was performed. The obtained reaction product was in a gel form, and a liquid resin could not be obtained.

(Comparative Example 3: B component and C component not used)
A 1 L four-necked round bottom flask equipped with a stirrer, thermometer and reflux condenser was prepared in the same manner as in the examples. And the following A component and D component and the low boiling-point type coupling agent as other components were prepared to this flask as an alternative of C component, and the liquid acrylic resin composition was obtained as follows. Specifically, 80 parts of BA, 20 parts of EA, which are specified by the present invention, 20 parts of EA are used, the B and C parts specified by the present invention are not used, and the other components are those having a boiling point of 150 ° C. or less. Decomposable alkoxysilyl group-containing coupling agent KBM-22 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., dimethyldimethoxysilane, boiling point 82 ° C.) is 100 parts, and further, L-SH is 2 as a chain transfer agent which is a D component. A part of the mixture was added and mixed by stirring to prepare a monomer mixture. And it heated up to 80 degreeC, and dissolved oxygen in the solution was removed by bubbling with nitrogen gas for 30 minutes with stirring. Then, while maintaining the internal temperature at 80 ° C., 2 parts of AIBN is added as a polymerization initiator which is the E component, and the polymerization reaction of the A component and the B component is started. In the presence of the chain transfer agent, the low boiling point silane A copolymerization reaction was carried out in the coupling agent, and the reaction was terminated after 8 hours. Then, it filtered for the purpose of removing an aggregate, and obtained the liquid acrylic resin composition of this comparative example.

  The viscosity of the liquid acrylic resin composition of this comparative example obtained above was 2300 (mPa · s / 25 ° C.). Further, the liquid acrylic resin composition of this comparative example was evaluated in the same manner as in the examples, and these results are shown in Table 2.

(Comparative Example 4: Component B is not used and toluene is used as a solvent)
A 1 L four-necked round bottom flask equipped with a stirrer, thermometer and reflux condenser was prepared in the same manner as in the examples. And the following A component, C component, D component, and toluene (boiling point: 110.6 degreeC) were prepared to this flask, and the solvent liquid acrylic resin was obtained as follows. Specifically, 60 parts of BA and 40 parts of EA, which are the A component defined in the present invention, are used, and KF-414 [trade name, manufactured by Shin-Etsu Chemical Co., Ltd., alkyl-modified silicone oil (hydrolysis) No viscosity alkoxysilyl group), viscosity 100 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)] 100 parts, D-component as chain transfer agent, L-SH as 1 part and other components, toluene 100 parts of was added and mixed by stirring to prepare a monomer mixture. And it heated up to 80 degreeC, and dissolved oxygen in the solution was removed by bubbling with nitrogen gas for 30 minutes with stirring. Then, while maintaining the internal temperature at 80 ° C., 1 part of AIBN was added as a polymerization initiator which is an E component to initiate a polymerization reaction of two types of A component, and in toluene in the presence of a chain transfer agent. A copolymerization reaction was performed, and the reaction was terminated after 8 hours. Then, it filtered for the purpose of removing an aggregate, and obtained the liquid acrylic resin composition which uses toluene of this comparative example as a solvent.

  The viscosity of the liquid acrylic resin composition using toluene as a solvent of this comparative example obtained above was 1450 (mPa · s / 25 ° C.). Moreover, about the liquid acrylic resin composition which uses toluene of this comparative example as a solvent, evaluation similar to what was performed in the Example was performed, and these results were shown in Table 2.

(Comparative Example 5: Water is used as a solvent)
A 1 L four-necked round bottom flask equipped with a stirrer, thermometer and reflux condenser was prepared in the same manner as in the examples. Then, 100 parts of ion-exchanged water and 2 parts of sodium polyoxyethylene alkyl ether sulfate (Levenol WX (trade name), manufactured by Kao Corporation, hereinafter referred to as “emulsifier A”) are added as an emulsifier to the flask. In addition, 80 parts of BA, 9 parts of MMA, 1 part of MAAC, and 10 parts of KBM-503, which is a B component prescribed in the present invention, are added as A component as defined in the present invention, and as C component , KF-414 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., alkyl-modified silicone oil (no hydrolyzable alkoxysilyl group), viscosity 100 mPa · s / 25 ° C., boiling point 150 ° C. or higher (measured value)), 100 parts, D component As a chain transfer agent, 2 parts of L-SH was added and stirred and mixed to prepare a monomer emulsified mixture. And it heated up to 80 degreeC, and dissolved oxygen in the solution was removed by bubbling with nitrogen gas for 30 minutes with stirring. Then, while maintaining the internal temperature at 80 ° C., 0.5 part of ammonium persulfate (abbreviated as APS) was added as a polymerization initiator, the polymerization reaction of the A component and the B component was started, and the reaction was terminated after 8 hours. Then, it filtered for the purpose of removing an aggregate and obtained the acrylic resin emulsion.

  The viscosity of the acrylic resin emulsion of this comparative example obtained above was 200 (mPa · s / 25 ° C.). Further, the acrylic resin emulsion of this comparative example was evaluated in the same manner as in the examples, and these results are shown in Table 2.

The symbols of the components shown in Table 2 are the same as those in Table 1 except for those shown below.
(C component)
● D-4000 (trade name): polypropylene glycol (molecular weight 4000), manufactured by NOF Corporation, viscosity 850 mPa · s / 25 ° C. (measured value), boiling point 150 ° C. or higher (measured value)

(E component)
● BPO: Benzoyl peroxide

(Other ingredients)
● KBM-22 (trade name): manufactured by Shin-Etsu Chemical Co., Ltd., dimethyldimethoxysilane, viscosity 100 mPa · s / 25 ° C. or less (measured value), boiling point 82 ° C. (boiling point is low, C component is not applicable)
MA440 (trade name): manufactured by Kaneka Corporation, silicone-modified acrylic resin, viscosity: 75000 mPa · s / 25 ° C., boiling point: 150 ° C. or higher (measured value) (high viscosity, not applicable as C component)
Emulsifier A: Sodium polyoxyethylene alkyl ether sulfate (manufactured by Kao Corporation, Lebenol WX (trade name))
● APS: ammonium persulfate (water-soluble polymerization initiator)

  As described above, the liquid acrylic resin compositions of Examples 1 to 9, which are solvent-free liquid acrylic resin compositions of the present invention, are excellent in any of room temperature curing, water whitening resistance, fluidity, adhesion, and odor. It became a thing. On the other hand, the acrylic resin composition of the comparative example which does not satisfy the requirements prescribed | regulated by this invention did not satisfy all. Specifically, as shown in Table 2, the solvent-free liquid acrylic resin composition having no hydrolyzable alkoxysilyl group derived from the component B of Comparative Example 1 is desired although it is room temperature curable. However, although it was possible to use the adhesive property, it was not sufficiently good. Moreover, the acrylic resin composition of the comparative example 2 which did not use D component which is a chain transfer agent at the time of reaction has gelatinized. Moreover, the acrylic resin composition of the comparative example 3 which did the copolymerization reaction in the silane coupling agent KBM-22 as a hydrolysable alkoxysilyl group containing compound with a boiling point of 150 degrees C or less, without using B component and C component. Although the fluidity was good, the odor was strong and room temperature curability could not be obtained. Further, the solvent-based acrylic resin composition of Comparative Example 4 which was reacted in toluene as the C component and the alkyl-modified silicone oil KF-414 containing no hydrolyzable alkoxysilyl group and the other component as the C component. Although the product has good fluidity, room temperature curability cannot be obtained, and there is a problem in terms of odor. Moreover, although the acrylic resin emulsion of Comparative Example 5 had no problem in terms of fluidity and odor, room temperature curability could not be obtained.

  As an application example of the present invention, the solventless liquid acrylic resin composition provided by the present invention does not contain a volatile organic solvent, so there is no problem of odor, excellent workability and environmental protection, and room temperature curing. It can also be moisture-curing, and the film formed even when left in warm water for a long time does not whiten, has excellent weather resistance, and has excellent transparency as needed. Furthermore, since the main monomer component is a (meth) acrylic acid alkyl ester monomer, it is inexpensive and has good adhesion and fluidity. For example, it is used outdoors in large quantities, The resin film is expected to be used as an adhesive for fixing gravel and aggregate, which is exposed to wind and rain. Further, the solventless liquid acrylic resin composition provided by the present invention can cover natural or artificial gravel or aggregate to fix gravel and the like, and at the same time, provides elasticity and / or vibration sound attenuation effect. Can be expected. In other words, the surface of gravel or aggregate is covered with a resin, and the vibration energy utilizing the viscoelasticity of the resin is converted into thermal energy, so that a vibration damping effect that attenuates the vibration energy is expected.

Claims (1)

A solvent-free liquid acrylic resin composition for fixing gravel or aggregate , which does not contain water and a volatile organic solvent as a solvent,
A component containing at least a copolymerizable (meth) acrylic acid alkyl ester monomer (a1) having no reactive functional group, and a hydrolyzable alkoxysilyl group-containing monomer copolymerizable with the A component When the total amount of the A component and the B component is 100 parts on a mass basis, the A component is in the range of 50 parts to 99 parts on a mass basis, and In the range where the B component is 1 part or more and 50 parts or less on a mass basis,
In the presence of a chain transfer agent (component D), in a liquid compound (component C) that has no copolymerizability with the component A, has a boiling point of 150 ° C. or higher and a viscosity at 25 ° C. of 50000 mPa · s or lower. Including a reaction product obtained by copolymerization,
When the total amount of the A component and the B component is 100 parts on a mass basis, the amount of the C component is 10 to 900 parts on a mass basis, and the R viscosity shown in the following formula (1) Is 100 mPa · s or more and less than 20000 mPa · s, and has a good fluidity-free solvent-free liquid acrylic resin composition (provided that the reaction product is a composition in which polysiloxane is mixed). except).
R viscosity = viscosity (mPa · s / 25 ° C.) × viscosity ratio (1)
Viscosity ratio = (B type viscometer minimum rotation 2rpm viscosity / B type viscometer maximum rotation 20rpm viscosity)