JPH0474392B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application)
Concerning general sealing materials for civil engineering, vehicles, equipment, etc.

(Prior art) Conventionally, as a sealant for construction or civil engineering, a soft porous synthetic resin foam is impregnated with a bituminous substance such as natural asphalt or petroleum resin, which is solid or semi-solid at room temperature, by melting under high temperature heat. things are widely used. The method for measuring initial water leakage from this sealant is as shown in Figure 1.
The sealing material to be tested is sandwiched between two transparent glass plates or acrylic resin plates measuring 150 mm by 300 mm in width in a U-shape with a spacer between them, with a constant compression ratio, and water is poured from the top into the U-shape. Height 55 inside
This was done by injecting water up to a depth of mm and holding it vertically for 24 hours to check for water leakage. By the way, the above-mentioned sealing material in which the bituminous material is impregnated into a porous material has low elasticity in low-temperature construction work below 0 degrees Celsius, and in order to obtain complete protection, a high compression ratio of 70 to 80% of the thickness is required in the above-mentioned test. Furthermore, the impregnated material itself becomes hard when it comes into contact with water, resulting in a decrease in rebound properties. In order to improve these points, in order to improve the hydrophobicity of the foam during urethane foaming or to provide waterproof properties, we have developed a foam stabilizer to modify the raw material polyol, modified the raw material blending side such as mixing water absorbing resin, and developed soft closed cell foam. Attempts have been made to connect foams (for example, JP-A-55-104330, JP-A-56-155275, JP-A-57-92032, JP-A-Sho 57-92032;
(No. 57-102978, Japanese Patent Application Laid-open No. 57-31976, etc.) The results of these water leakage tests are superior to those impregnated with bituminous material, and the compressibility is as low as 20 to 30% relative to its thickness. However, the waterproof effect is excellent and has sufficient elasticity even at low temperatures.Also, since these are not impregnated, there is no leakage of impregnating liquid or contamination even at high temperatures of 80 to 100 degrees Celsius, but the basic principle is that the raw materials are mixed. Due to these problems, it was not possible to handle small lot production, and due to restrictions such as foam thickness, it was not possible to handle a large variety of products due to dimensions.

The present inventors previously demonstrated that by impregnating a polyurethane foam obtained by the reaction of polycaprolactone and isocyanate with a water- and oil-repellent agent or a waterproofing agent, water retention for more than 24 hours was observed in the water leakage test described above. They discovered a good sealing material and have already applied for a patent. (Special application 1986-52871
However, the soft polyurethane foam used in this method uses a special raw material called polycaprolactone polyol, and the foaming method is also special, making it expensive and disadvantageous in terms of production costs. It is.

Therefore, the present inventors have completed the present invention as a result of various studies to improve such drawbacks and find similar effects for general grade flexible open-cell foams. Watertight, using soft open-cell polyurethane foam
Our goal is to provide highly airtight sealants.

(Means for Solving the Problems) That is, the present invention involves dissolving in water an aqueous organic fluorine-based water and oil repellent or waterproofing agent in a soft or semi-rigid open-cell polyurethane foam obtained by reacting a polyol with a diisocyanate. Alternatively, it is a sealing material characterized by being impregnated with a treatment liquid obtained by dispersing the sealant. Here, the flexible open-cell polyurethane foam used in the present invention is produced by mixing a polyol component, a polyisocyanate component, and a blowing agent and reacting them according to a conventional method. are used to produce this type of polyurethane foam, such as polyethers such as poly(oxypropylene ether) polyol, poly(oxyethylene-propylene ether) polyol, or poly(ethylene adipate), poly( butylene adipate), poly(diethylene adipate), or mixtures thereof.As the diisocyanate component, those used in the production of ordinary flexible polyurethane foams may be used, such as tetramethylene diisocyanate, hexamethylene diisocyanate, cyclohexane-1 ,4
-diisocyanate, 1,4-phenylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, etc., and these may be used alone or in combination. Examples of the blowing agent include water, halogenated alkanes such as monofluorotrichloromethane and dichloromethane, low-boiling alkanes such as butane and pentane, and azobisisobutyronitrile which generates decomposed nitrogen gas. Furthermore, catalysts such as tertiary amines and organic tin compounds commonly used in polyurethane reactions, and other auxiliary agents such as crosslinking agents, silicone compounds (foam control agents), ultraviolet absorbers, antioxidants, and flame retardants are added. You may.

The water- and oil-repellent agent or waterproofing agent used in the present invention must be an aqueous organic fluorine-based agent.
That is, there are two types of water and oil repellents: organic solvent type and water dispersion type or water soluble type, but in the present invention, water-based water and oil repellents are used because they are used in a solution or dispersion state to impregnate foaming water. It is extremely advantageous to use . As a result of testing and examining various water and oil repellents, they found that organic fluorine-based agents were the most effective. The aqueous organic fluorine water and oil repellent used in the present invention is _C3 ~
An organic fluorine compound having a _C20 fluoroalkyl group or a fluoroalkenyl group, this water and oil repellent is a homopolymer of a vinyl monomer having a _C3 to _C20 fluoroalkyl group or a fluoroalkenyl group. Or a copolymer of this with a vinyl monomer that does not contain fluorine, a C ₃ -C ₂₀ which may be fluorinated with a monohydric or polyhydric alcohol having a C 3 -C 20 fluoroalkyl group or _a fluoroalkenyl group.
(Poly) with C ₂₀ mono- or polycarboxylic acids
C ₃ - _{C 20} which may be ester or fluorinated
Examples include (poly)esters of alcohols and mono- or polyhydric carboxylic acids having a C ₃ to _{C 20} fluoroalkyl group or fluoroalkenyl group.
Preferably, for example,
C ₇ F ₁₅ CH ₂ OCOCH=CH ₂ ,
C ₈ F ₁₇ CH ₂ CH ₂ OCOCH=CH ₂ ,
C ₁₀ F ₁₉ OCH ₂ CH ₂ OCOCH=CH ₂ ,
C ₁₀ F ₁₉ OCH ₂ CH ₂ OCOCH=CH ₂ , C ₈ F ₁₇ SO ₂ N
Homopolymers such as (C ₃ H ₇ ) CH ₂ CH ₂ OCOCH=CH ₂ ,
Alternatively, it is a mutual copolymer of these or a copolymer of these and a vinyl monomer.

In the present invention, the means for impregnating the organic fluorine-based water and oil repellent or waterproofing agent is to prepare an aqueous solution or aqueous dispersion of the above-mentioned organic fluorine compound, and immerse the polyurethane foam in this solution at room temperature or under heating, or The polyurethane foam is easily impregnated by applying it onto the surface of the polyurethane foam.

However, if foaming is excessive during the impregnation step of the water and oil repellent used in the present invention, it is preferable to further add an antifoaming agent to the bath. In other words, when the foam is kneaded in an impregnating bath to impregnate it with an organic fluorine-based water and oil repellent, it is easily absorbed, but at the same time, if foaming is intense, an antifoaming agent may be added to the bath. , this point is improved.

Next, the present invention will be specifically explained using examples.

Example 1 Water and oil repellent consisting of a water emulsion containing 20% of the active ingredients as main components of the copolymer shown below.
A treatment bath was prepared by mixing 18 gr with 300 gr of water.

Copolymer component C ₈ F ₁₇ CH ₂ CH ₂ OCOCH=CH ₂ 75 parts by weight C ₄ H ₉ OCOCH=CH ₂ 23 parts by weight CH ₂ = CHCONHCH ₂ OH 2 parts by weight Semi-rigid polyurethane foam Sekisisofuran is added to this treatment bath. Made #505 20m/m x 20m/m x 250
m/mL (apparent specific gravity 0.04gr/cc) approximately 10gr per bottle
After impregnation and drying, heat treatment was performed at 160°C for 1 minute.
In the water leak test under 50% compression, water leaked after about 17 hours, and the water level at 19 hours was 40 m/m (55 m/m at the start of the test).
m/m).

Note that the same flexible polyurethane foam that was not treated with water and oil repellents leaked water after 10 minutes.

Example 2 12 gr of the same water and oil repellent used in Example 1
Mix with 300g of water and add Nopcor as an antifoaming agent.
A treatment bath was prepared by adding 1.0 g of 8034L (manufactured by San Nobuco), and to this was added the same semi-rigid polyurethane foam (apparent specific gravity 0.04 gr/cc) as in Example 1, 20 m/m x 20
Each m/m x 250 m/mL (about 5 gr) was impregnated with about 10 gr, and after drying, treatment was performed at 160°C for 1 minute. When this sample was subjected to a water leakage test under 50% compression in the same manner as in Example 1, no water leakage occurred even after 24 hours or more under 50% compression.

(Effects) As described above, the present invention provides construction materials with extremely good watertightness and airtightness by impregnating soft or semi-rigid polyurethane foam with an aqueous organic fluorine-based water and oil repellent or waterproofing agent. Other sealing materials for civil engineering, vehicles, equipment, etc. can be obtained.In particular, in the present invention, since the impregnating liquid is an aqueous dispersion or an aqueous solution, this type of impregnating liquid is conventionally used as an organic solvent-based sealant. In addition to being advantageous in terms of safety and industrial accidents, many organic solvents have an adverse effect on the physical properties of polyurethane itself because they dissolve and swell soft polyurethane foam. It also has the effect of improving these points.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram for measuring water leakage of the sealant of the present invention. 1...Glass plate (acrylic resin plate), 2...Test object, 3...Spacer.

Claims (1)

[Claims] 1 A soft or semi-rigid open-cell polyurethane foam obtained by reacting a polyol and a diisocyanate is impregnated with a treatment liquid obtained by dissolving or dispersing an aqueous organic fluorine-based water and oil repellent or waterproofing agent in water. Characteristic sealing material.