JPS63273663A - Production of polyurethane foam containing bituminous substance - Google Patents

Abstract

PURPOSE:To obtain a polyurethane foam containing a bituminous substance, having fine cells and excellent mechanical properties, using a specific polyisocyanate and adding the bituminous substance to a raw material and expanding by the use of both a foam stabilizer and a foam breaker. CONSTITUTION:(A) A polyurethane raw material comprising a polyisocyanate containing polymethylene polyphenylene isocyanate (preferably mixture of polymethylene polyphenylene isocyanate and tolylene diisocyanate), a polyol and a blowing agent is blended with (B) preferably 10-80wt.% (based on foam composition) bituminous substance solid or semisolid at normal temperature such as straight asphalt having 10-200 penetration and expanded by the use of (C) a foam stabilizer (silicone stabilizer or sorbitan monostearate) and a foam breaker (silicone foam breaker or polybutene foam breaker) to produce the aimed foam having excellent characteristics readily.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for producing polyurethane foams containing bituminous material. More specifically, the present invention relates to an improvement in a method for producing a polyurethane foam by mixing a solid or semi-solid bituminous material with a polyurethane raw material at room temperature and foaming the mixture.

Polyurethane foams containing bituminous materials are useful as waterproof sealants and sound absorbing materials.

Prior Art Conventionally, the following method has been known as a method for producing polyurethane foam containing a bituminous material such as asphalt.

(1) A method in which a pre-manufactured polyurethane foam is impregnated with a solution prepared by dissolving a bituminous material such as asphalt in a volatile solvent, and then dried.

(2) A method in which an aqueous emulsion of asphalt is reacted with a urethane prepolymer obtained by reacting a hydrophilic polyether polyol (added with an ethylene oxide content of 15% by weight or more) and an organic isocyanate (Japanese Unexamined Patent Application Publication No. 1983-1999).
No. 213029).

(3) A method of mixing asphalt with polyurethane raw materials and foaming them.

However, method (11) is economically disadvantageous because it requires a large amount of volatile solvent, and it takes a long time to dry this solvent, which only reduces productivity.
It has drawbacks such as not being easy to handle (and uneven impregnation occurs).

In method (2), it is necessary to use a hydrophilic polyol containing 15% or more of ethylene oxide, otherwise it will mix with asphalt emulsion, and the resulting foam will have poor waterproof properties. In addition, water remains in the foam and gradually evaporates, causing the physical properties of the foam to change over time.

In method (3), when a urethane raw material is mixed with a bituminous material such as asphalt that is solid or semi-solid at room temperature and foamed, the temperature must be raised to a high temperature in order to make the bituminous material fluid. becomes.

Therefore, the method of controlling foaming characteristics by increasing or decreasing the amount of catalyst has the disadvantage that the reaction rate changes significantly. Furthermore, asphalt has very large variations in quality due to differences in quality depending on the country of origin of crude oil, and when a large amount of bituminous material is mixed in, there are many difficulties in controlling the foaming characteristics using conventional catalysts.

Purpose of the Invention The present invention has been made to overcome the drawbacks of conventional methods, and is a method of adding a bituminous material that is solid or semi-solid at room temperature to a polyurethane raw material, for which it has been difficult to obtain a polyurethane material with good foaming characteristics. A method of mixing and foaming to produce a bituminous-containing polyurethane foam, wherein the bituminous-containing polyurethane foam has good foaming properties, fine cells and excellent mechanical performance (e.g. strength, elongation). To provide a method for manufacturing the body.

Structure of the Invention In order to achieve the above-mentioned object, the present inventors have conducted intensive research, and as a result,
Polyurethane raw materials (polyol, blowing agent.

When foaming a bituminous material with polyisocyanate (such as polyisocyanate), if polymethylene polyphenylene isocyanate is used as the polyisocyanate and a foam stabilizer and foam-breaking agent are used in combination, foaming will occur even at high temperatures. A polyurethane foam with good properties, fine cells, low air permeability, and evenly dispersed bituminous material, excellent waterproof properties, and excellent mechanical properties such as strength and elongation can be obtained. I was able to find out what was going on. The present invention was completed based on this knowledge.

The gist of the present invention is a method for producing a flexible polyurethane foam containing a bituminous material that is solid or semi-solid at room temperature, in which the bituminous material is contained in the raw material, and polymethylene polyphenylene isocyanate is used as the polyisocyanate. A method for producing a polyurethane foam containing a bituminous material, characterized in that foaming is carried out using a foam stabilizer and a foam-breaking agent in combination.

Polymethylene polyphenylene isocyanate (hereinafter abbreviated as MDI) is used as a polyisocyanate as a raw material for the polyurethane foam used in the method of the present invention.
It is necessary to use

In the present invention, 101 includes 4,4'-diphenylmethane diisocyanate, which has been modified with carbodiimide and liquefied.

MDI may be used alone or in combination with other polyisocyanates, and may also be used as a prepolymer containing terminal isocyanate groups obtained by reacting it with a compound containing active hydrogen. For example, it is preferable to use a mixture of MDI and tolylene diisocyanate because it increases elongation and improves strength.The mixing ratio is such that 2.5% or more of the total polyisocyanate is M-old.

When MDI is mixed, Examples 2 to 5 and Comparative Examples 1 to 2
As can be seen from the comparison with Foaming Properties 1, mechanical performance is improved, reactivity (shorter curing time), air permeability is reduced, and sound absorption is improved.

As the polyol, in addition to general polyurethane polyols, polyether polyols, and polyester polyols, dimer acid polyols, castor oil polyols, and the like can be used alone or in mixtures.

Typical bituminous materials that are solid or semi-solid at room temperature include stray asphalt, door asphalt, and blown asphalt, each having a penetration of 10 to 200. In addition, in order to improve cold resistance, adhesion, and fluidity, process oils that are blended into general solid rubber, tars such as coal tar and petroleum oil tar, and 04 or higher fractions that are produced as by-products during naphtha cracking are used. , preferably C5”CIl
It is also possible to use residues of petroleum resins, various synthetic resins, or synthetic oils obtained by copolymerizing monomers in the fraction.

The amount of bituminous material added varies depending on the required performance such as waterproofness, vibration damping, sound absorption, etc., but it is preferably 10 to 80% by weight in the foam composition; if it exceeds 80%, the mechanical properties deteriorate and it is not practical. becomes difficult to serve.

The foam stabilizer used in the present invention may be one that is used in the production of general polyurethane foams, and includes, for example, silicone foam stabilizers, sorbitan monostearate, glycerin monooleate, and the like. As the silicone foam stabilizer, a polydimethylsiloxane-polyalkylene ether block copolymer is preferred, and a polydimethylsiloxane-polyalkylene ether block copolymer having a terminal OH group is particularly preferred.

Foam breakers used in the present invention include silicone-based, polybutene-based, paraffin-based, and wax-based. Examples of silicone-based foam breakers include dimethyl silicone oil, methylfer silicone oil, and the like. Further, modified versions of these materials, such as epoxy-modified or carboxy-modified ones, may also be used.

In general, the general formula %formula% C However, R is hydrogen, an alkyl group, or an aryl group.

Substituted alkyl group, substituted alkyl group, aralkyl group.

The substituted aralkyl group is preferably one in which n represents O or an integer.

Examples of polybutene-based foam breakers include polymers mainly composed of isobutylene, which are commercially available as liquid polybutene.

Examples of paraffin-based foam-breaking agents include liquid paraffin and chlorinated paraffin, and examples of wax-based foam-breaking agents include paraffin wax and carnauba wax.

Only when the foam-breaking agent is used in combination as a foam stabilizer in the presence of MDI will the foaming properties be good, the cells become fine, and the bituminous material evenly dispersed.

If a foam-breaking agent is not added, the foam cells will not be connected, and even if they are connected, the foaming properties will be poor and it cannot be applied to actual production.Also, if a foam-breaking agent is used in the absence of MDI,
The cell stability is poor, resulting in coarse cells, poor waterproofing properties, and poor foaming properties.

In addition to the above-mentioned foam raw materials, natural rosin is also used.

Plasticizers such as ester gum, polyisoprene, coumaron-indene resin, xylene resin, tertiary-butylphenol resin, and terpene resin, as well as calcium carbonate, barium sulfate, alumina, talc, diatomaceous earth, clay, etc., which are added to general plastics. Kaolin, mica,
Fillers or reinforcing materials such as asbestos, glass fiber, gypsum, silica gel, carvone, various fibers, etc. may be added.

The foam may be manufactured by any of the Wanchorat method, the prepolymer method, and the one-part prepolymer method (the foam may be in any form, such as a slab, a mold, a string, a plate, and a cylinder).

Example 1 OHH obtained from dimer acid and diethylene glycol
100 parts of CO2 polyol (parts indicate parts by weight, the same applies hereinafter), straight asphalt (penetration 80-100)
) 150 parts, aromatic process oil (CA8
5. Idemitsu Kosan) 50 parts, silicone foam stabilizer 1 part, Dab
Thoroughly mix 0.2 parts of co 33LV (manufactured by Sankyo Air Products Co., Ltd., amine catalyst), 0.2 parts of stannous octylate, and 0.05 parts of silicone foam-breaker (polydimethyl silicone oil), and heat at 75°C. To this, 3.0 parts MD of water was heated.
60 parts of I (MDI-CR manufactured by Mitsui Toatsu Co., Ltd.) were added and stirred rapidly to obtain a foam.

The resulting foam has extremely fine cells with a density of 0.121 g/cm3 and an air permeability of 1.2 cc/5ec-12,
The waterproof property at 50% compression was good for 24 hours or more at a water pressure of 10 cn.

Examples 2-5゜Hydroxyl value 28, ethylene oxide 30%, number of functional groups 3
100 parts of polyether polyol A, Dabco-3
3LV (manufactured by Sankyo Air Products, amine catalyst) 0
．． 2 parts, dibutyltin dilaurate 1.0 part, silicone foam stabilizer 1.0 part, silicone foam breaker (dimethyl silicone oil-KF96, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.14 part,
Straight asphalt (penetration 80-100) 240
parts were mixed and heated to 70°C. This at 600°rpm
While stirring, 4.3 parts of water was added, and a mixture of toluene diisocyanate (T-65) and crude polymethylene polyphenylene isocyanate (MDI-CR, manufactured by Mitsui Toatsu) was added at an NGO10H equivalent ratio of 1.3 parts. A foam was obtained by mixing at a ratio of 0.05 to 0.05. The performance of the obtained foam was as shown in Table-1.

Comparative Example 1゜By the method of Example 2, MDI-
All foaming was performed under the same conditions except for CR and T-65 being used alone. The performance of the obtained foam was as shown in Table-1.

Comparative Example 2 Foaming was carried out under the same conditions as in Example 2 except that the silicone foam-breaking agent KF96 was not used. The performance of the obtained foam was as shown in Table-1.

As is clear from the comparison between Example 2 and Comparative Examples 1 and 2,
The method of the present invention has excellent foaming properties and appearance, low air permeability with thin cells, excellent waterproofing properties, and excellent mechanical properties such as tensile strength and elongation.

Example 6 100 parts of a polyol obtained by addition polymerizing propylene oxide and ethylene oxide of glycerin with a hydroxyl value of 56 and a functional group of 3, 3.5 parts of water, Dabco-33LVO03
1 part, 0.2 parts of stannous octoate, 2 parts of silicone foam stabilizer
Part, silicone foam breaker (KP96) (same as above) 0
．． Thoroughly mix 1 part to prepare liquid A. On the other hand, 126 parts of strained asphalt (penetration 80-100), T-6540
1 part and 10 parts of H old-CR were mixed and heated to 50°C to obtain liquid B.

A foam was obtained by mixing liquids A and B. The resulting foam has good foaming properties, with a density of 0.065 g/cm3, fine cells and air permeability of 3.5 cc/5ec-cs, tensile strength of 0.6 kg/am, and elongation of 130%. It was a good value.

Water resistance was 8 hours at 5 cm water pressure.

Example 7゜Polyol A used in Example 2 and T-65 part MDI-
150 parts of NGO = 16.9% prepolymer obtained from CR (20/1), 3.8 parts of water, 2 parts of dibutyltin dilaurate, 1.0 part of silicone foam stabilizer, silicone foam breaker A premix was prepared by mixing 1 part of KFO60.

Add straight asphalt at 90℃ to this premix (
Penetration: 80-100) 245 parts and 3.8 parts of water were added, and the mixture was thoroughly stirred and foamed to obtain a foam. .

The obtained foam has excellent foaming properties and a density of 0.099 g/
cm", tensile strength 0.51 kg/cab", elongation 130%, air permeability 1.5 cc/see -C! 1" micro-cell foam, waterproofing is 7C at 50% compression.
Water pressure of 111 was good for 24 hours. The results of measuring the sound absorption coefficient of this foam are shown in FIG.

Note that the flexible foam shown in the figure is a commercially available foam that does not contain asphalt.

The air permeability in each example was measured using a woven fabric air permeability tester using a foam with a thickness of 10B, and the method was JISL-10.
Conforms to 04.

As shown in Fig. 2, the waterproof property was determined by compressing the sample by 50% by placing it in a U-shape on an acrylic plate, injecting water from above to a predetermined water pressure, and observing the time it took for water to leak.

Effects of the Invention According to the method of the present invention, the following excellent effects can be achieved.

(1) Even if the polyurethane raw material contains a bituminous material and is foamed, a foam with excellent mechanical performance can be obtained.

(2) Since the foam has fine cells, low air permeability, and bituminous substances are uniformly dispersed, it is possible to contain a large amount of bituminous substances and is not sticky.

(3) Since the foam has the above-mentioned excellent properties, it has excellent waterproof properties and excellent sound absorption coefficient at medium and low frequencies.

(4) Even if a large amount of bituminous material is mixed in, the foaming characteristics can be controlled stably.

[Brief explanation of the drawing]

FIG. 1 shows the measurement results of the sound absorption coefficient of the foam obtained in Example 7, and FIG. 2 shows a waterproof measuring device. Engraving of the drawings (no changes to the old version) Figure 1 JilVL (Hz) Figure 2 Procedural amendment dated August 1985 Kunio Ogawa, Commissioner of the Patent Office 1, Indication of the case 1988 Patent Application No. 107959 No. λ Name of the invention i! ! FF-containing polyurethane foam manufacturing method 3, relationship with the amended case Patent applicant address 1 Shinisogo-cho, Isogo-ku, Yokohama, Kanagawa Prefecture Name (
464) NHK Spring Co., Ltd. 4, Agent 160 Telephone: 356-6090 July 28, 1988 (shipment date) Engraving of the drawing originally attached to the application, as attached (no changes to the content)

Claims (1)

[Claims] In a method for producing a flexible polyurethane foam containing a bituminous material that is solid or semi-solid at room temperature, the bituminous material is contained in the raw material, polymethylene polyphenylene isocyanate is used as the polyisocyanate, and a foam stabilizer is used. A method for producing a polyurethane foam containing a bituminous material, characterized by foaming using a combination of a foam-breaking agent and a foam-breaking agent.