JP3991343B2 - Resin pavement enforcement method using self-emulsifying primer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an isocyanate group-terminated compound-containing self-emulsifying primer for resinous pavement and an enforcement method using the same.
[0002]
[Prior art]
Conventionally, resin-based pavements have been used for athletic stadiums, tennis courts, promenades, etc., mainly for impact absorption. A typical example is a paving material in which rubber chips are consolidated with urethane resin. On the other hand, recently, resin pavements using urethane resin, epoxy resin, acrylic resin, etc. have been devised for the purpose of low noise, mirror burn countermeasures, wrinkle prevention and the like on the roadway.
[0003]
The lower ground of these resin-based pavements is concrete, asphalt concrete or the like, but generally a primer is used to improve the adhesion to the ground surface. As the primer, one obtained by diluting an isocyanate-terminated prepolymer with a volatile solvent such as toluene or ethyl acetate to reduce the viscosity is used, and a strong adhesive force is obtained.
For example, JP-A-55-98504 discloses a primer comprising 20 parts of a prepolymer having a NCO group content of 7.5% and 50 parts of toluene, which is obtained by reacting a TDI isocyanate and polyoxypropylene glycol, and 50 parts of crude MDI. A primer composed of a% xylene solution is described, and after applying these primers, a method of paving with a paving material mainly composed of a synthetic resin emulsion is described.
[0004]
[Problems to be solved by the invention]
However, these primers are odorous because they contain volatile solvents, and workers are always at risk of organic solvent poisoning. In addition, there is a possibility of causing a fire due to ignition. Both toluene and xylene used in JP-A-55-98504 are type 2 organic solvents regulated by the organic solvent regulations of the Industrial Safety and Health Act, and have a boiling point of 110 ° C., a flash point of 4 ° C., Xylene has a boiling point of about 140 ° C. and a flash point of about 24 ° C.
Therefore, it is difficult to use it in urban areas or densely populated houses, and it is extremely difficult to use it in places where solvent vapor is likely to stay, such as in tunnels.
[0005]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have found that the problem can be solved by using a primer containing a self-emulsifying isocyanate compound, and the present invention has been completed.
[0006]
That is, the present invention is a resin paving primer, which is an alkoxy (polyoxyalkylene) glycol (provided by adding ethylene oxide, ethylene oxide, or propylene oxide to an organic polyisocyanate and a monoalcohol having 1 to 6 carbon atoms. , Ethylene oxide or the total number of moles of ethylene oxide and propylene oxide added is 5 or more, the number of moles of ethylene oxide added> the number of moles of propylene oxide) , or ethylene oxide or ethylene oxide in a monoalcohol having 1 to 6 carbon atoms , Alkoxy (polyoxyalkylene) glycol obtained by adding propylene oxide (provided that ethylene oxide or the total number of added moles of ethylene oxide and propylene oxide is 5 or more, ethylene oxide The number of added moles of id> the number of added moles of propylene oxide) and an active hydrogen group-containing compound having an average functional group number of 2 to 3 and a number average molecular weight of 62 to 5000
A self-emulsifying primer containing a hydrophilic isocyanate group-terminated compound obtained by reacting with a high-boiling point thinning agent at the construction site, and the primer / water in a weight ratio of 20/80 to 80/20. The mixture is applied as an emulsion to the base surface, and after curing, the synthetic resin is pulverized, or the mixture of the pulverized resin and inorganic particles is mixed with a binder and spread on the primer surface. And paving method.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The organic polyisocyanate used in the present invention is 4,4'-diphenylmethane diisocyanate (hereinafter abbreviated as MDI), 2,4'-MDI, 2,2'-MDI, polymethylene polyphenylene polyisocyanate (hereinafter referred to as polymeric MDI). Abbreviation), 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, crude tolylene diisocyanate, para-xylylene diisocyanate, meta-xylylene diisocyanate, ortho-xylylene diisocyanate, 1,5-naphthylene diisocyanate, Para-phenylene diisocyanate, meta-tetramethylxylylene diisocyanate, para-tetramethylxylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-di Chloromethane diisocyanate, cyclohexyl diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, a mixture of two or more of the above polyisocyanates, carbodiimide-modified products of these polyisocyanates, burettes There are various modified isocyanates such as modified products, uretdione modified products, and isocyanurate modified products.
[0011]
Of these various organic polyisocyanates, MDI polyisocyanates such as 4,4′-MDI, carbodiimide-modified N4DI, and polymeric MDI are desirable from the viewpoint of vapor pressure, price, and the like. Specific products include Millionate MT, Millionate MTL, Millionate MR100, Coronate 1107, etc. manufactured by Nippon Polyurethane Industry.
[0012]
The self-emulsifying property is imparted to an organic polyisocyanate by adding ethylene oxide, ethylene oxide, or propylene oxide to a monoalcohol having 1 to 6 carbon atoms, but an alkoxy (polyoxyalkylene) glycol (however, ethylene oxide or ethylene oxide). The total number of added moles of propylene oxide is 5 or more, and by adding the number of added moles of ethylene oxide> the number of added moles of propylene oxide, self-emulsification is achieved.
The arrangement of the ethylene oxide unit and the propylene oxide unit in the alkoxy (polyoxyalkylene) glycol may be random or block, and the unit bonded to the alkoxy group may be either an ethylene oxide unit or a propylene oxide unit.
The alkoxy (polyoxyalkylene) glycol has a number average molecular weight of 250 to 5,000, and methoxy polyethylene glycol having a number average molecular weight of 300 to 600 is preferred from the viewpoint of versatility.
The amount of alkoxy (polyoxyalkylene) glycol to be added is 2.5 to 25 parts by weight with respect to 100 parts by weight of the organic polyisocyanate.
[0013]
The active hydrogen group-containing compound used in the second invention is a polyether polyol, polyester polyol, polycarbonate polyol, castor oil, modified castor oil-based polyol having a number average molecular weight of 62 to 5000 and an average functional group number of 2 to 3. In view of price, viscosity of the resulting composition, etc., polyether polyol is preferred, and polypropylene glycol is most preferred.
[0014]
Further, low molecular polyols and polyamines having a number average molecular weight of less than 500, which are generally called chain extenders, are also included in the active hydrogen group-containing compound. For example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, glycerin, trimethylolpropane, ethylenediamine, hexamethylenediamine, isophoronediamine and the like.
[0015]
This active hydrogen group-containing compound has the effect of improving the adhesion and flexibility to the pavement and the base surface. The amount used is 10 to 300 parts by weight with respect to 100 parts by weight of the organic polyisocyanate.
[0016]
The hydrophilic isocyanate group-terminated compound in the present invention has an average functional group number of 1.8 to 3.5, desirably 2.0 to 3.0. In the synthesis, the ratio of isocyanate group / active hydrogen group, so-called isocyanate index, is 2 or more, preferably 3 or more. When the raw material organic polyisocyanate is polymeric MDI, the isocyanate group content of the reaction product is preferably 10 to 30%. The reaction method is obtained under a nitrogen atmosphere, at a reaction temperature of 20 to 120 ° C., preferably 50 to 90 ° C.
[0017]
When the average number of functional groups is 1.8 or less, the adhesive strength of the primer obtained is low and peeling occurs easily. When the average number of functional groups is 3.5 or more, the primer obtained is hard and brittle and easily peels off due to vibration or the like. With respect to the isocyanate index of 2 or less, the primer obtained has a weak adhesive force and generally becomes a high-viscosity product, resulting in poor workability.
[0018]
In order to improve the emulsification workability at the time of construction, it is also an effective method to add a high boiling point thinning agent such as alkylene carbonate immediately after synthesis or just before emulsification. The amount added is preferably 50 parts by weight or less, more preferably 20% by weight or less, based on 100 parts by weight of the prepolymer. If the viscosity after mixing is 200 to 2500 mPa · s / 25 ° C., workability is good. A desirable high boiling point thinning agent is propylene carbonate. Propylene carbonate has a boiling point of 242 ° C. and a flash point of 132 ° C.
[0019]
The isocyanate group-terminated self-emulsifying primer of the present invention is made into an emulsion by mixing isocyanate group-terminated self-emulsifying primer / water at a weight ratio of 20/80 to 80/20 on site immediately before primer application. At this time, in order to reduce the viscosity and improve the emulsifiability, a thickener may be added as described above, or a primer already added with a thinning agent may be used. The emulsion is applied to the base surface using a known tool such as roller coating or rubber rake. The coating amount varies depending on the type and state of the base surface, but is generally 50 to 300 g / m ² in terms of solid content.
[0020]
The base surface to which the primer is applied is preferably cured at room temperature for about 1 hour. Examples of the paving method after curing include the following methods.
A method in which a synthetic resin such as a rubber chip is pulverized, or a mixture of pulverized resin and inorganic particles such as sand is mixed with a binder such as a moisture-curing urethane resin and spread on a primer surface.
The curing time of the surface on which the primer is applied is preferably adjusted by the water absorption, lipophilicity, humidity at the time of enforcement, etc.
[0021]
【The invention's effect】
Since the isocyanate group-terminated compound-containing self-emulsifying primer of the present invention does not contain a volatile solvent, there is no concern for workers to cause solvent poisoning and the problem of odor is low. Also, it is a highly safe primer with no possibility of ignition at room temperature. This makes it easy to use in densely populated houses and tunnels that were difficult to use in the past. In addition, since it contains a hydrophilic isocyanate group-terminated prepolymer, it exhibits a strong adhesive strength equal to or higher than that of conventional solvent-diluted types, not only when the substrate is dried, but also when wet after rain. To do.
[0022]
【Example】
EXAMPLES Examples are given below to describe the self-emulsifying primer for resinous pavement of the present invention and the method for using the same, but the present invention is not limited to this. In the synthesis examples, examples and comparative examples, “parts” and “%” represent “parts by weight” and “% by weight” unless otherwise specified.
[0023]
Synthesis example 1
950 parts of Polymeric MDI (manufactured by Nippon Polyurethane Industry Co., Ltd., Millionate MR100) is stirred at 45 ° C. in a synthesis apparatus in which a stirrer, a thermometer, a cooling pipe, and a nitrogen gas introduction pipe are assembled, and 50 parts of methoxypolyethylene glycol having a number average molecular weight of 400 is stirred. After adding gradually, it reacted at 75-85 degreeC for 3 hours, and obtained the isocyanate group terminal prepolymer (P-1). The isocyanate content of P-1 was 28.8%, and the viscosity was 300 mPa · s / 25 ° C.
[0024]
Synthesis example 2
In a synthesis apparatus including a stirrer, a thermometer, a cooling pipe, and a nitrogen gas introduction pipe, 100 parts of 4,4′-MDI (manufactured by Nippon Polyurethane Industry, Millionate MT), 350 parts of polymeric MDI (manufactured by Nippon Polyurethane Industry, Millionate MR100) The mixture was stirred at 45 ° C., 400 parts of polypropylene glycol having an average functional group number of 2 and a number average molecular weight of 2200, and 50 parts of methoxy polyethylene glycol having a number average molecular weight of 400 were gradually added, and then reacted at 75 to 85 ° C. for 3 hours. After cooling to 50 ° C., 100 parts of propylene carbonate was added to obtain an isocyanate group-terminated prepolymer-containing primer (P-2). The isocyanate content of P-2 was 12.1%, and the viscosity was 1400 mPa · s / 25 ° C.
[0025]
Comparative Example 1
An isocyanate-terminated prepolymer (P-2) was obtained in the same manner as in Synthesis Example 1, except that polyethylene glycol having a number average molecular weight of 800 and a functional group number of 2 was used instead of methoxypolyethylene glycol having a number average molecular weight of 400. The isocyanate content of P-2 was 12.1%, and the viscosity was 1700 mPa · s / 25 ° C.
[0026]
Reference example 1
When 50 parts of the primer (P-2) of Synthesis Example 2 and 50 parts of water were mixed for 30 seconds, a yellowish white emulsion was obtained. The viscosity of this emulsion was as low as 30 mPa · s / 25 ° C.
[0027]
Comparative Example 2
50 parts of the composition (P-2) of Comparative Example 1 and 50 parts of water were mixed for 30 seconds, but did not disperse, and phase separation occurred when stirring was interrupted.
[0028]
Example 1
When 50 parts of the primer (P-1) of Synthesis Example 1 and 50 parts of water were mixed for 30 seconds, a yellowish white emulsion was obtained. This emulsion was applied onto a slate plate by roller coating, corresponding to 80 g / m 2 (in terms of solid content). One hour later, using a mold, a mixture of 50 parts of waste tire rubber chips, 30 parts of No. 5 silica sand, and 20 parts of an isocyanate group terminal moisture-curing binder (manufactured by Nippon Polyurethane Industry, Coronate 4569) to 4 cm × 4 cm and a thickness of 1.5 cm Homing. After curing for 2 weeks in a constant temperature room at 25 ° C., the peel strength of the primer surface was measured according to JIS A5908. The peel strength was 1.0 MPa, which was the same strength as Comparative Example 3 shown below. It was.
[0029]
Example 2
When 50 parts of the primer (P-2) of Synthesis Example 2 and 50 parts of water were mixed for 30 seconds, a yellowish white emulsion was obtained. This emulsion was applied onto a slate plate by roller coating, corresponding to 80 g / m 2 (in terms of solid content). One hour later, using a mold, a mixture of 50 parts of waste tire rubber chips, 30 parts of No. 5 silica sand, and 20 parts of isocyanate group terminal moisture curing binder (Nihon Polyurethane Industry Co., Ltd., Coronate 4569) is 4 cm × 4 cm in thickness 1.5 cm Homing. After curing for 2 weeks in a constant temperature room at 25 ° C., the peel strength of the primer surface was measured according to JIS A5908. The peel strength was 1.3 MPa, which was the same strength as Comparative Example 3 shown below. It was.
[0030]
Comparative Example 3
Polymeric MDI / castor oil based isocyanate-terminated prepolymer (toluene / ethyl acetate = 50/50, solid content = 50%, NCO content = 6%, viscosity = 50 mPa · s / 25 ° C.) on a slate plate by roller coating 80 g / m2 equivalent (solid content conversion) was applied. After 1 hour, using a mold, a mixture of 50 parts of waste tire rubber chips, 30 parts of No. 5 silica sand, and 20 parts of an isocyanate group terminal moisture-curing binder (manufactured by Nippon Polyurethane Industry, Coronate 4569) to 4 cm × 4 cm and a thickness of 1.5 cm Homing. After curing for 2 weeks in a thermostatic chamber at 25 ° C., the peel strength of the primer surface was measured according to JIS A5908. The peel strength was 1.2 MPa. There was a solvent odor during application. The primer flash point was 1 ° C.
[0031]
Example 3
When 50 parts of the primer (P-2) of Synthesis Example 2 and 50 parts of water were mixed for 30 seconds, a yellowish white emulsion was obtained. This emulsion was applied onto a wet concrete plate with a roller brush by a roller coating equivalent to 150 g / m 2 (in terms of solid content). One hour later, using a mold, homing a mixture of 40 parts of EPDM rubber chip, 35 parts of No. 7 silica sand and 25 parts of isocyanate group terminal moisture curing binder (Nihon Polyurethane Kogyo Co., Ltd., Coronate 4569) to 4 cm x 4 cm, thickness 1.5 cm did. At 25 ° C. temperature-controlled chamber, after curing for 10 days, was measured peel strength at TateKenshiki small adhesion peel tester (BA-400), peel strength is 1.3 MPa, the following Comparative Example Greater than 4 .
[0032]
Comparative Example 4
An isocyanate group terminal solvent dilution type primer (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate 2460, toluene / ethyl acetate) was applied onto the same wet concrete plate as in Example 5 by roller coating, equivalent to 150 g / m 2 (converted to solid content). After 1 hour, using a mold, a mixture of 40 parts of EPDM rubber chip, 35 parts of 7 silica sand, and 25 parts of isocyanate group terminal moisture curing binder (manufactured by Nippon Polyurethane Industry, Coronate 4569) was homed to 4 cm × 4 cm and a thickness of 1.5 cm. . After curing for 10 days in a thermostatic chamber at 25 ° C., when the peel strength was measured with a Kenken-type small adhesion peel tester (BA-400), the peel strength was 0.9 MPa. There was a solvent odor during application. The primer flash point was 1 ° C.

Claims (1)

A resinous paving primer, which is an alkoxy (polyoxyalkylene) glycol obtained by adding ethylene oxide, ethylene oxide, or propylene oxide to an organic polyisocyanate and a monoalcohol having 1 to 6 carbon atoms (however, ethylene oxide or ethylene) The total number of moles added of oxide and propylene oxide is 5 or more, the number of moles added of ethylene oxide> the number of moles added of propylene oxide) , or
Alkoxy (polyoxyalkylene) glycol obtained by adding ethylene oxide or ethylene oxide or propylene oxide to monoalcohol having 1 to 6 carbon atoms (however, the total number of added moles of ethylene oxide or ethylene oxide and propylene oxide is 5 or more) The number of moles of ethylene oxide added> the number of moles of propylene oxide added), and an active hydrogen group-containing compound having an average functional group number of 2 to 3 and a number average molecular weight of 62 to 5000
A self-emulsifying primer containing a hydrophilic isocyanate group-terminated compound obtained by reacting with a high-boiling point thinning agent
At the construction site, the primer / water is mixed at a weight ratio of 20/80 to 80/20 as an emulsion, applied to the ground surface, and after curing, the synthetic resin is crushed, or the pulverized resin and inorganic particles A pavement method comprising mixing a mixture with a binder and spreading the mixture on the primer surface.