JPH0459882A - Adhesive for rubber powder - Google Patents

Abstract

PURPOSE:To obtain the subject adhesive having long pot-life, giving sufficiently high adhesive force between rubber powder particles and useful for elastic pavement material, a cushion material, a vibration damping material, etc., by using a specific compound and a terminal isocyanate urethane prepolymer as essential components. CONSTITUTION:The objective adhesive contains (A) a compound of formula ((n) is 2-4) (preferably terephthalyl chloride) and (B) a terminal isocyanate urethane prepolymer derived from (i) a polyol (preferably a polypropylene glycol having a molecular weight of 200-4,000 and an average number of functional groups of 2-2.5) and (ii) a stoichiometrically excessive polyisocyanate (preferably diphenylmethane-4,4'-diisocyanate) preferably at a ratio (A:B) of (0.005-0.1):1.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an adhesive for bonding rubber powder together.

[Prior art] A one-component moisture-curing urethane resin or a two-component urethane resin is used as an adhesive, and rubber powder is hardened into a sheet cane to be used as a base material for elastic paving materials, shoe sheen materials, single-floor vibration-proofing materials, etc. Its use is known. In order to improve the adhesive strength between rubber powders, a method is known in which the rubber powders are treated with a urethane resin curing catalyst (e.g.
85642).

[Problem II to be solved by the invention] However, although this method increases the adhesive strength of rubber powder,
The problem is that the viscosity increases quickly after mixing the rubber powder and urethane resin, which worsens workability during sheet production.

[Means for Solving the Problems] The present inventors have conducted intensive studies to find a rubber powder adhesive that improves the adhesiveness between rubber powders and has good workability, and as a result, the present invention has been developed. Reached.

(In the formula, n is either 2..3 or 4.) and (B) a terminal isocyanate urethane prepolymer made from a polyol and a stoichiometrically excess positive isocyanate. It is a rubber powder adhesive characterized by being a component.

Component (A) in the present invention includes terephthalyl chloride, isophthalyl chloride, phthalyl chloride, 1,2゜4-benzenetricarboxylic acid trichloride, 1,2゜3-benzenetricarboxylic acid trichloride, 1,3゜5-benzene. Tricarboxylic acid trichloride, 1,2°3.4-
Benzenetetracarboxylic acid tetrachloride and the like can be used. Among these, preferred is terephthalyl chloride.

The raw material polyol for the urethane prepolymer (B) in the present invention includes polymer polyols such as polyether polyols, polyester polyols, polymer polyols, polybutadiene polyols, and mixtures of two or more thereof.

As polyether polyols, low molecular polyols (
Ethylene glycol, propylene glycol, 1,4-
Trifunctional polyols such as butanediol and 1,3-butanediol; trifunctional or higher functional polyols such as glycerin, trimethylolpropane, pentaerythritol, and sucrose), amines (alkanolamines nolamine; aliphatic polyamines such as ethylenediamine) ; aromatic polyamines such as tolylene diamine, methylene dianiline, polymethylene polyphenylamine, etc.); oxide, butylene oxide, etc.), ring-opening polymers of alkylene oxides (ring-opening polymers of tetrahydrofuran,
Polyester polyols include polycarboxylic acids (aliphatic polycarboxylic acids such as adipic acid, maleic acid, dimerized sulfuric acid, aromatic polycarboxylic acids such as phthalic acid); Polyester polyols, lactone polyesters (polycaprolactone polyols, etc.) obtained by condensation with polyols (low-molecular polyols or polyether polyols as mentioned above); Polyols obtained by polymerizing vinyl monomers (acrylonitrile and/or styrene, etc.); polybutadiene polyols include those obtained by polymerizing butadiene with a hydroxyl group-containing radical initiator, and anionic polymers of sodium, lithium, etc. Examples include those obtained by adding a compound that becomes a hydroxyl group, such as ethylene oxide, to an active end polymer obtained by polymerizing butadiene using a catalyst.

Among these polymer polyols, polyether polyols are preferred, and polypropylene glycol is particularly preferred. The molecular weight of the high molecular weight polyol is usually 20'o=eo60, preferably 200 to 400.
It is 0. If a polymer polyol with a molecular weight greater than e6oo is used, the resin strength after curing will be weakened, making it impossible to obtain a tough paint film. The (average) number of functional groups of the polyol is usually 1.8 to 4.01, preferably 2.
-3, particularly preferably 2-2.5.

In the present invention, the polyisocyanates used as raw materials for the prepolymer component (B) include aromatic polyisocyanates, such as 2.4-) lylene diisocyanate, 2.8-) lylene diisocyanate, 2.
A mixture of 4-tolylene diisocyanate and 2-tolylene diamine anate, xylylene diisocyanate,
Diphenylmethane-4,4'-diisocyanate, diphenylmethane-4, which is liquid at room temperature.

Modified polyisocyanates based on 4'-diisocyanate (such as carposiimide modification), 1,3-bis(
phenylmethyl isocyanate, etc.; aliphatic polyisocyanates such as normal aliphatic polyisocyanates such as hexamethylene diisocyanate, araliphatic polyisocyanates such as xylylene diisocyanate; alicyclic polyisocyanates such as infron diisocyanate, cyclohexane-1, Examples include 4-diisocyanate, 1,4-methylenebis(cyclohexyl isocyanate), and mixtures of two or more thereof. Among these, aromatic polyisocyanates are preferred, and diphenylmethane-4,4'-diisocyanate is particularly preferred.

The prepolymer (B) in the present invention is obtained by reacting the above-mentioned polyol and polyisocyanate in a proportion that produces an incyanate-terminated prepolymer (a proportion that produces a stoichiometric excess of polyisocyanate), The equivalent ratio (NGO10H ratio) is usually 7 to 0.8,
Preferably it is 5-2.

Urethane prepolymer (B) is usually obtained by reacting the above polyol and polyisocyanate at 70 to 110°C for 1 to 20 hours. The isocyanate group content of the urethane prepolymer is usually 5 to 20% by weight, preferably 7 to 12% by weight.

The ratio of component (A) and component (B) is usually 0.0 by weight.
05:1 to 0.2:1, preferably 0,005
:1 to 0.1:1.

In addition to the components (A) and (B), a crosslinking agent, a catalyst, and an additive may be added to the components in the present invention as necessary. In addition to the above-mentioned low-molecular-weight polyols, 4
, 4'-methylenebis(2-chloroaniline), 4.4
'-methylenebis(2,3-dichloroaniline), 3,
Aromatic polyamines such as 5-diamino-4-chloro-methyl-Henschede can be used.

Among these, preferred are aromatic polyamines,
Particularly preferred is 4,4'-methylenebis(2-chloroaniline). The ratio of the component (B) prepolymer and crosslinking agent is the usual equivalent ratio! :0 to l:1.5,
Preferably it is 1:0 to 1:0.9.

Catalysts include amine catalysts such as triethylamine, triethylenediamine, N,N'-dimethylpiperazine and N-ethylmorpholine; acid catalysts such as octylic acid, adipic acid and azelaic acid; metal catalysts such as dibutyltin dilaurate, dibutyltin malate, Examples include stannath octoate, bismuth chloride, lead octylate, and ferric acetylacetonate; and combination systems of two or more of these. Among these, metal catalysts are preferred, and dibutyl tin malate is particularly preferred.

Additives include reinforcing agents (carbon black, white carbon, colloidal silica, etc.), inorganic fillers (calcium carbonate, barium sulfate, talc, clay, silica powder, etc.), and plasticizers (dibutyl phthalate, dioctyl phthalate, chlorinated normal paraffin). etc.), diluents (petroleum resins, xylene resins, etc.), solvents (toluene, xylene, methyl ethyl ketone, ethyl acetate, etc.), anti-aging agents, flame retardants, and colorants.

Rubbers to which the composition of the present invention can be applied include, for example, natural rubber, polyisobutylene rubber, styrene-butadiene rubber,
Polybutadiene rubber, butyl rubber, chloroprene rubber,
Examples include polyurethane rubber.

Examples of the rubber powder include rubber powder, rubber pieces (for example, rubber pieces from waste tires), and the like.

The amount of adhesive used is normally 15
It is 0-400g.

In the present invention, the order of application is completely arbitrary as long as components (A) and (B) are essential components. (A), (B
) and any optional ingredients added as necessary are simultaneously mixed with rubber powder, a sheet is created by pressure bonding if necessary, (A) or (A) diluted in a solvent is first mixed with rubber powder. Then, any method may be used, such as successive mixing of (B) or a mixture of (B) and an optional component added as necessary with the rubber powder, or, if necessary, forming a sheet by pressure bonding. In addition, there are no restrictions on the mixing method, including hand mixing and mixing by machines (hand mixer, mortar mixer, planetary mixer, etc.).
Optional. Furthermore, the sheet production method can be arbitrarily selected, such as press forming in a factory, spreading on site, and rolling.

After application, component (B) in the present invention reacts with moisture in the atmosphere or with an optionally added crosslinking agent to form a strong adhesive layer.

[The exact mechanism of action of the action co-component (A) is unknown, but by acting on the unsaturated bonds of rubber molecules and increasing the surface polarity, it increases the interaction between the rubber and urethane resin interface, and improves the adhesion of rubber pine. It is estimated that this contributes to improving the adhesion between the agent layers.

[Example] The present invention will be further explained with reference to Production Examples and Examples, but the present invention is not limited thereto. The parts described below indicate parts by weight.

Production Example I 725 parts of polypropylene glycol having a number average molecular weight of 3000 and a functional group number of 2 was placed in a four-bottle flask equipped with a stirring bar and a thermometer, and the mixture was heated to 110 parts under a reduced pressure of 3i+mHg.
The mixture was heated to ℃ and dehydrated for 1 hour. Next, 275 parts of diphenylmethane-4,4'-diisocyanate was added,
A prepolymer [B1] was obtained by reacting at 100° C. for 3 hours under a nitrogen stream. The incyanate content of prepolymer [B11] was 7.2%.

Production Example 2 550 parts of polypropylene glycol with a number average molecular weight of 2,000 and a functional group number of 2 and 5 parts of polypropylene glycol B with a number average molecular weight of 100 and a functional group number of 3 were placed in a four-bottle flask equipped with a stirring bar and a thermometer, and 3 m
Dehydration was carried out for 1 hour by heating to 110° C. under a reduced pressure of 1.5 dg. Next, 275 parts of diphenylmethane-4,4#-diisocyanate was added and reacted at 100° C. for 5 hours under a nitrogen stream to obtain prepolymer [B11]. Prepolymer [
The incyanate content of B11 was 9.8%.

Production Example 3 3.5 parts of terephthalyl chloride was dissolved in 100 parts of ethyl acetate to obtain a treatment liquid [A].

Production Example 4 1 part of triethylenediamine was dissolved in 100 parts of ethyl acetate to obtain a treatment liquid [C].

Example 1 - Production of adhesive 1 part of terephthalyl chloride was added to too much of the prepolymer [B 1] and thoroughly stirred and mixed to obtain an adhesive [B1'].

Further, 1 part of phthalyl chloride was added to 100 parts of prepolymer [821] and thoroughly stirred and mixed to obtain adhesive [B2'].

Example 2 - Workability and rubber powder adhesive strength measurement test A Mu 1. 80 parts of waste tire rubber powder (particle size 2-5) consisting of natural rubber and styrene-butadiene rubber and adhesive [B
1' were sufficiently stirred and mixed. Of this formulation, 200 g was transferred to another container, and the time when stirring became impossible (pot life) was measured. In addition, 72g of the conjugate was added to 10. Oc Peng X 10. 81 in the formwork of Oc■
The material was spread to a thickness of 100 ml and kept at 20° C. for 7 days. By measuring the tensile strength of the sheet according to JIS K6301 (dumbbell No. 1, tensile speed 40 mm/in),
The adhesive strength between rubber powders was measured.

Mu 2. A similar test was conducted by replacing the adhesive [B1'] with [B2'].

Example 3 - Workability and rubber powder adhesive strength measurement test B B-1. Processing liquid [A] was added to 80 parts of the same rubber powder as in Example I.
After adding 3 parts, the mixture was stirred and mixed, and then dried at room temperature for 30 minutes.

Next, 8,120 parts of the prepolymer was added to the treated rubber powder and thoroughly stirred and mixed. Of this formulation, 200
g was transferred to another container, and the time when stirring became impossible (pot life) was measured. In addition, 172 g of the mixture was added to 10.0 c Peng X ]0. It was spread on an Oc layer formwork to a thickness of 8 mm and cured at 20° C. for 7 days. JI the sheet
The adhesive strength between rubber powders was measured by keeping the tensile strength (dumbbell No. 1, tensile speed 40 vs/s+in) constant with oil according to SKIi301.

B-2, prepolymer [B1 was replaced with [B11], and the same test as in Example 2 was conducted.

Comparative Example 1 Workability and Rubber Powder Adhesive Strength Measurement Test C C-1. The same test as in Example 2 was conducted except that the adhesive [B1'] was replaced with the prepolymer [BI Co].

C-2, the same test as in Example 3 was conducted except that the treatment liquid [A] was replaced with [C].

The test results of Examples and Comparative Examples are shown in Table-■ and Table-2.

Table 1: Provides good workability such as maintaining a long pot life after the example, and provides sufficient adhesive strength between rubber powders. Because it has such an effect, the adhesive of the present invention hardens rubber powder into a sheet shape.
It can be applied to elastic paving materials, cushioning materials, vibration-proofing materials, floor base materials, etc.

The adhesive of the present invention is also useful as a paint for rubber Table 2 Comparative example [Effect of the invention]

Claims (1)

[Claims] 1. (A) A compound represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (I) (wherein, n is any one of 2, 3, or 4) and ( B) A rubber powder adhesive characterized in that it comprises as an essential component a terminal isocyanate urethane prepolymer made from a polyol and a stoichiometric excess of polyisocyanate. 2. The composition according to claim 1, wherein (A) is terephthalyl chloride. 3. The weight ratio of component (A) and component (B) is 0.005:1
3. Adhesive according to claim 1 or 2, wherein the ratio is ˜0.1:1.