JPH01146921A - Polyisocyanate dispersion composition - Google Patents

Abstract

PURPOSE:To obtain the title composition comprising an isocyanate component which gives a polyurethane polyurea product having excellent strength and toughness, by dispersing a reactive metallic carboxylate in a polyisocyanate compound in the specified proportion. CONSTITUTION:A caustic alkali is added to an aqueous suspension of a carboxylic acid having a group containing active hydrogen atoms to form a neutralized solution, which is mixed an aqueous solution of a chloride of a desired metal, thus giving a reactive metallic carboxylate (B) of formula I (wherein X is a group having active hydrogen atoms, such as amino, OH or COOH; m is 1-2; M is a polyvalent metal such as Al, Ca, Ti, Cr, Fe, Co, Ni, Cu, Zn, Cd, Sn, Ba or Pb; f is a number equal to the valence of metal M; n is 1-f). Component B is dispersed in a polyisocyanate compound (A) having a number-average molecular weight of 250-8,000 and at least two NCO groups in the molecule in the proportion of A to B to provide an isocyanate index of formula II of 100-2,000, preferably 200-1,000, thus giving the title composition in which the mean particle diameter of the dispersoid is 0.01-20mum, preferably 0.01-5mum.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a polyisocyanate dispersion composition useful as an isocyanate component for polyurethane and polyurea, and more particularly to a polyisocyanate dispersion composition useful as an isocyanate component for polyurethane and polyurea, and more specifically, for imparting strength and toughness to polyurethane and polyurea products produced by reaction injection molding. This invention relates to a new incyanate dispersion composition.

Conventional technology A technique for producing an article made of polyurethane or polyurea elastomer by reacting a polymer compound having an active hydrogen atom, a chain extender, and a polyisocyanate compound in a closed mold using a reaction injection molding (RIM) method. It is attracting attention especially in the automobile industry and other fields. As such technology, for example, US Patent No. No. 4,254°069, US Pat. No. 4,272,618; U.S. Pat. No. 3,523,918 disclosing the use of amine chain extenders for the production of skin layered foams: polymeric polyols, certain aromatic diamines and U.S. Pat. No. 4,218,543 using isocyanate compounds; other U.S. Pat. No. 4,2
46,363, 4,269.945, European Patent Application No. 92,672, 93,861, 93,86
A large number of studies have been reported, such as No. 2, No. 81,701, and JP-A-60-4516.

In the conventional RIM method, the so-called he-component is a pure polyisocyanate, or a polyisocyanate is partially reacted with a polyol or a polyamine.

It should be noted that any isocyanate of the pseudoprebolymer in which isocyanate groups remain is contained, and the B-component contains a polymer compound having an active hydrogen atom and a chain extender for forming a skin layer, and optionally It contains catalysts, plasticizers, flame retardants, stabilizers, colorants, fillers such as glass fiber or milled glass, mold release agents, etc., and these components are injected into a closed mold and allowed to react. Molded products are obtained, and are divided into RIM molded products that do not use reinforcing fillers and R-RIM molded products that use fillers.

However, even in the system where a filler is added as described above,
Glass surfaces generally have poor compatibility with polyols, and even if compatibility is improved by treatment with a silane coupling agent, the strength improvement effect is no more than a simple filler filling effect, and RIM, R-RIM It is desired to further improve the mechanical properties of products.

Problems to be Solved by the InventionTherefore, there is a need for a method to further improve the strength, toughness, and mechanical properties of polyurethane and polyurea products by reaction injection molding compared to conventional techniques, and to find a simple and reliable method for this purpose. This is the main purpose of the present invention.

Means for Solving the Problems According to the present invention, the above-mentioned object of the invention is to provide a polyisocyanate compound having a number average molecular weight of 250 to 8,000 and having two or more isocyanate groups in the molecule with the formula (wherein X is an amino group,
A group having an active hydrogen atom selected from the group consisting of a hydroxyl group and a carboxyl group; m is 1 or 2; M is ^1, C
a, Ti, Cr, Fe, Co, Ni, Cu, Z
n, a polyvalent metal selected from the group consisting of Cd, Sn, Ba and Pb; f is a number equal to the valence of metal M; n is a positive integer from 1 to r). The average particle size of the dispersoid obtained by dispersing the isocyanate index expressed by the following formula at a blending ratio such that the isocyanate index is greater than 100 and is within the range of 2000 or less is 0.01 to 2.
This can be achieved by using a polyisocyanate dispersion composition for polyurethane and polyurea that has a particle diameter of 0μ.

The polyisocyanate component for polyurethane or polyurea is a compound that has two or more extremely reactive incyanate groups in its molecule, so traditionally fillers, catalysts, stabilizers, and other additives are the other reaction raw materials. It is added to the polyol or polyamine component, but no consideration has been given to adding it to the polyisocyanate component.

Further, the filler used in the R-RIM method was only used in anticipation of its filler filling effect (volume effect, shape effect). However, the present inventors added a certain particulate material to the polyisocyanate component, chemically bonded it to the polyisocyanate, and reacted with the polyol or polyamine component to form the particulate material into an intramolecularly bonded form. It was discovered that when introduced into polyurethane or polyurea, it imparts mechanical properties such as strength and toughness that are far superior to a mere filler filling effect, and this is the basis of the present invention. That is, according to the present invention, a specific amount of a specific carboxylic acid metal salt is added to a polyisocyanate compound, and these reactants are dispersed and contained in the polyisocyanate compound as a dispersoid to produce an isocyanate for polyurethane or polyurea. Novel dispersion compositions useful as components are provided.

The polyisocyanate compound used in the preparation of the dispersion composition of the present invention is any liquid organic polyisocyanate that contains two or more isocyanate groups in the molecule and has an average molecular weight of 250 to 8,000 and is used in the production of ordinary polyurethane or polyurea. Alternatively, it is a partially reacted prepolymer of organic polyisocyanate and polyether or polyamine, known as a pseudo-prepolymer. A wide variety of aromatic polyisocyanates may be used in the present invention. Typical aromatic polyisocyanates include P-phenylene diisocyanate, polymethylene polyphenylisocyanate, 2,6-toluene diisocyanate, dianisidine diisocyanate, bitolylene diisocyanate, naphthalene-1,4-diisocyanate, bis(4
-incyanatophenyl)methane, bis(3-methyl-3-isocyanatophenyl)methane, bis(3-methyl-4-isocyanatophenyl)methane and 4.
4'-diphenylpropane diisocyanate is mentioned.

Other aromatic polyisocyanates used in the practice of this invention are methylene-bridged polyphenyl polyisocyanate mixtures having a functionality of 2 to 4. These latter isocyanate compounds are generally combined with formaldehyde and
They are prepared by phosgenation of the corresponding methylene-bridged polyphenylpolyamines prepared by reacting aromatic amines such as aniline in the presence of hydrochloric acid and/or other acidic catalysts. Known processes for the production of polyamines and correspondingly for the production of methylene-crosslinked polyphenyl polyisocyanates are described not only in the literature but also in numerous patents (e.g. U.S. Pat. No. 2,683,730;
No. 950,263, No. 3,012,008, No. 3
．． 344,162 and 3,362.979).

Generally methylene-crosslinked polyphenylbolyisocyanane I.
The mixture contains from 20 to 100% by weight of methylene diphenyl diisocyanate isomers; the remainder is polymethylene polyphenyl diisocyanate with higher functionality and higher molecular weight.

These typically contain 20 to 100% by weight of methylene diphenyl diisocyanate isomers.
5% by weight of the 4.4°-isomer) and the remainder a polymethylene polyphenyl polyisocyanate having a higher molecular weight and an average functionality of 2.1 to 3.5. It is an isocyanate mixture. These isocyanate mixtures are known and commercially available materials and are prepared by the method described in US Pat. No. 3,362,979.

Particularly preferred aromatic polyisocyanates are pure MD
methylene bis(4-phenylisocyanate) in the form I, or MDI, pseudo-prepolymers of MDI, modified pure MDI, etc. These types of materials can be used to make suitable RIM elastomers. Since pure MDI is a solid and therefore often inconvenient to use, liquid products based on MDI are often used, which is the term used in this case:
It falls within the scope of MDI or methylene bis(4-phenylisocyanate). U.S. Patent No. 3,394,
No. 164 discloses examples of liquid MDI products.

Furthermore - for boat fishing, uretonimine modified MDI is also included in the above definition. This product is produced in the presence of a catalyst in pure distilled M
Manufactured by heating DI. The liquid product is a mixture of pure MDI and modified MDI. Commercially available products of this type include Isocyanate 125M and 143L from Abjon.

As described above, in the present invention, any compound used as an isocyanate component for polyurethane or polyurea and a pseudo-prepolymer obtained by reacting them with an active hydrogen atom-containing substance are used. It is called "polyisocyanate". The average molecular weight of such polyisocyanate is usually 250 to 80.
It is within the range of 00. This is because anything less than this has not been put to practical use, and anything above 8,000 tends to lose its liquid form suitable for use for the purpose of the present invention.

In the present invention, the polyisocyanate has the following formula (where X is a group having an active hydrogen atom selected from the group consisting of an amino group, a hydroxyl group, and a carboxyl group; m is 1 or 2; M is A!, Ca, Ti , Cr, Fe, C
o, Ni, Cu, Xn, Cd, Sn, Ba and p
a polyvalent metal carried from the group consisting of b; f is a number equal to the valence of metal M; n is a positive integer from 1 to f). A specific amount of a reactive carboxylic acid metal salt is blended. Such reactive carboxylic acid metal salts are described, for example, in Journal of the Japan Rubber Association, Vol. 56, No. 1θ, 613-620 (+911
As described in 3), caustic alkali is added to an aqueous suspension of a carboxylic acid having a group having an active hydrogen atom to obtain a neutralized solution, and then an aqueous chloride solution of the desired metal is added. Manufactured by Since such compounds have good affinity with rubber and dispersibility, they are blended into NBR etc. in the form of fine particles of about 0.5 to several microns, and are used as rubber modifiers for improving tensile strength and reinforcing purposes. However, there have been no reports on its application to elastic materials such as polyurethane and polyurea. The present inventors continued research into the application of the above-mentioned reactive carboxylic acid metal salts to polyurethane elastomers, and surprisingly found that when added to the polyisocyanate component rather than to the polyol component, the elastomer's rupture occurred. It was discovered that the initial Young's modulus, tensile strength, etc. can be significantly improved without affecting the offshore modulus, and this discovery is an important basis for the present invention.

The above-mentioned reactive carboxylic acid metal salt contains a group having an active hydrogen atom represented by X with or without an OH group, and such an active group easily reacts with the isocyanate group of the polyisocyanate compound at room temperature. , urethane, urea, acyl urethane bonds, etc., and can be easily linked to polyisocyanate compounds. The present inventors have discovered that the combined product of the reactive carboxylic acid metal salt and the polyisocyanate compound produced in this reaction has an average particle size of 0. O1~20
It is dispersed and contained in the polyisocyanate compound as micro-sized particles, and as long as a sufficient amount of isocyanate groups involved in the reaction with the polyol or polyamine component remain in the particles, it is extremely useful as an incyanate component for R-RIM or RIM. It was discovered that this gives an elastic product with significantly improved mechanical properties.

Reactive carboxylic acid metal salts exist in the form of particles in which many molecules are bonded or aggregated, and polyisocyanate compounds also usually exist in the form of a composition rather than a compound represented by a single formula. Regarding the blending ratio of the two, it is more convenient to use the incyanate index rather than the equivalent ratio. The present inventors found that when the incyanate index expressed by the amount of the reactive carboxylic acid metal salt is greater than 100, it is 2.
It is convenient for the purpose of the invention that j1 is selected to have a value of 000 or less, preferably 200 to 1000, and the reactant produced by the reaction of both is dispersed and contained in the polyisocyanate dispersion medium as a dispersoid. However, the average particle size of the dispersoid is o, oi ~ 20μ, preferably 0.0
It has been found that it is convenient for the purpose of the invention to prepare the particles to have a particle size of 1 to 5 μm. Isocyanate index is 1
If it is less than 00, no reactive isocyanate group remains and is not incorporated into polyurethane or polyurea molecules.
Moreover, when it exceeds 2000, the strength due to carboxylic acid metal salt,
This is because the effect of improving toughness cannot be sufficiently obtained, and particles having an average particle size of more than 20 μm or smaller than 0.01 μm are also disadvantageous for the intended purpose. Therefore, a predetermined amount of the above-mentioned reactive carboxylic acid metal salt is added to the polyisocyanate, and the average particle size of the dispersoid is adjusted to 0, O1 by known means such as high-speed stirring and dispersion using glass beads.
It is necessary to control it within the range of ~20μ.

The thus obtained incyanate dispersion according to the present invention is composed of a reaction product of a polyisocyanate and a reactive carboxylic acid metal salt of the above formula in a liquid polyisocyanate compound, and has an average particle size of 0. This is a composition in which particles of O1 to 20μ are dispersed, with isocyanate groups remaining on the surface and sufficiently retaining reactivity with polyols or polyamines, and can be used as is or together with other polyisocyanate compounds in RIM or An elastic molded product with significantly improved mechanical properties such as initial Young's modulus and tensile strength when used in combination with a composition containing a polymer compound having active hydrogen atoms, a chain extender, etc. for R-RIM. It is extremely useful as a raw material for polyurethane and polyurea in the automobile industry and other fields.

The present invention will be explained below with reference to Examples.

Example 1 Literature (Japan Rubber Association Journal Vol, 56. PP, 613
620 (1983)), P-amine benzoic acid aluminum salt (hereinafter abbreviated as PAIAL) was prepared according to the following procedure.

After suspending 137 g of para-aminobenzoic acid in 500+nj' ion-exchanged water, it is slowly neutralized with 200 cal of a 20% aqueous sodium hydroxide solution to obtain a sodium para-aminobenzoate aqueous solution. Separately, put 10 g of crystalline aluminum chloride in a reaction vessel equipped with a stirrer and add 200 g of ion-exchanged water! Dissolve with. To this solution, the previously prepared sodium para-aminobenzoate aqueous solution was added dropwise at room temperature with vigorous stirring. After the completion of 8 dropwise additions, the mixture was heated to about 50° C. with stirring and allowed to react for 3 hours.

The generated precipitate was filtered, thoroughly washed with distilled water to remove sodium chloride, and finally washed with methanol. After washing, the precipitate is dried at 50'C under reduced pressure until it reaches a constant weight, resulting in solid crystalline PABAL (functional group equivalent lθ6).
I got it.

10' parts by weight of PABAl was added to commercially available crude diphenylmethane-4,4'-diisocyanate (trade name Nimillionate MTL, manufactured by Nippon Polyurethane Industries, Ltd., number average molecular weight 29).
0, isocyanate equivalent = approximately 145 > 83 parts by weight (isocyanate index -6 (IQ)), and was dispersed with high speed stirring using glass beads as a medium to obtain a dispersion composition with an average particle size of 2μ. 93 parts by weight of polyether polyol (
Product name: ^M-505, manufactured by Asahi Denka Kogyo ■, hydroxyl group equivalent -
1560>71 parts by weight, and ethylene glycol (
Manufactured by Wako Tsumugi Kogyo ■, reagent 1st class, hydroxyl group equivalent = 31) 1
RI at a ratio of 3 parts by weight (isocyanate index = 105>
M molding was performed to obtain a cured product. Raw material temperature and mold temperature are each 4
The temperatures were 0°C and 60°C. The initial Young's modulus, tensile strength, and elongation at break of the cured product were measured according to STMD638, and the heat resistance was tested according to STMD 3769 at a test temperature of 160°C.The results are shown in Table 1. It was shown to.

Example 2 4 parts by weight of crude diphenylmethane to 3Q parts by weight of solid crystalline 2,4-hydroxybenzoic acid iron salt (functional group equivalent: 76)
,4'-diisocyanate (Product name: Millionate MT
114 parts by weight (L, manufactured by Nippon Polyurethane Industry ■, isocyanate equivalent = 145) were added and dispersed using glass beads as a medium to obtain a composition with an average particle size of 3 μm.

To 114 parts by weight of the above composition, 84 parts by weight of polyether polyol (trade name: AM-505, manufactured by Asahi Denka Kogyo ■, hydroxyl equivalent = 1560) and ethylene glycol (manufactured by Wako Tsumugi Kogyo ■, reagent grade 1, Hydroxyl group equivalent = 3
Ratio of 1 > 9 parts by weight (isocyanate index = 11
0> to obtain a cured product. The raw material temperature and mold temperature were 40°C and 60°C, respectively.

This cured product was tested for initial Young's modulus, tensile strength, elongation at break, and heat resistance in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 Literature (Journal of Japan Rubber Association VQl, 56. PP, 613
~620 (1983)), PABA according to the following steps.
L was prepared.

After suspending 137q of para-aminobenzoic acid in 5(lI]mJ' of ion-exchanged water, it was slowly neutralized with 200J of 20% sodium hydroxide aqueous solution to obtain a sodium para-aminobenzoate aqueous solution. Separately equipped with a stirrer. Place 80 g of crystalline aluminum chloride in a reaction container and add 2 ml of ion-exchanged water.
Dissolve at 00 mJ. To this solution, the previously prepared aqueous solution of para-amino ammonia and sodium fragrant is added dropwise at room temperature with vigorous stirring. After the dropwise addition was completed, the mixture was heated to about 50° C. with stirring and allowed to react for 3 hours.

The formed precipitate was filtered and thoroughly washed with distilled water to remove the arsenic salt, and then washed with methanol after i.

After washing, the precipitate is dried at 50°C under reduced pressure until it reaches a constant weight, resulting in solid crystalline PABAL (functional group equivalent: 106).
I got it.

1'ABAL 10 parts by weight of polyether polyol (
Product name: AM-505, manufactured by Asahi Denka Kogyo ■, hydroxyl equivalent = 1560) 71 parts by weight and ethylene glycol (
Manufactured by Wako Pure Chemical Industries, 1st grade reagent, hydroxyl equivalent = 31) 1
It was mixed into 3 parts by weight of a mixed solution and dispersed with high speed stirring using glass beads as a medium to obtain a dispersion having an average particle size of 2 μm.

Commercially available crude diphenylmethane was added to 94 parts by weight of this dispersion.
4,4°-Diisocyanate (Product name: Millionate M
TL, manufactured by Nippon Polyurethane Kogyo f-toko, Isocyaner I.
equivalent weight = 145) 83 parts by weight ratio (isocyanate index =
105> to obtain a cured product, the raw material temperature and mold temperature were 40°C and CIOoC, respectively.

Comparative Example 2 In solid crystal form, 2.4 to hydroxybenzoic acid iron salt (functional group superimposition ≠ 76) 3 (+ parts by weight and polyether) (trade name: AM-505, Asahi Den f Hiegyo 1' body) Made by
114 parts by weight of hydroxyl equivalent = +560) and 9 parts by weight of ethylene glycol (manufactured by Aiko Pure Chemical Industries, 1st grade reagent, hydroxyl equivalent: -31) were mixed in a solution, and dispersed using glass beads as a medium. , a composition with an average particle size of 211 was obtained.

Ratio of 114 parts by weight of crude diphenylmethane-4,4'-diizocyanate-1 (trade name: Millionate MT, manufactured by Nippon Polyurethane Industries (1), isocyanate equivalent = 145) to 123 parts by weight of the dispersion. (Isocyanate index = 110), the material temperature and mold temperature were 40° C. and 160° C., respectively.

The cured products of each comparative example were tested for initial Young's modulus, tensile strength, elongation at break, and heat resistance in the same manner as in Example 1, and the results are shown in Table 1.

(Margin below)

Claims (3)

[Claims] (1) Polyisocyanate compounds with a number average molecular weight of 250 to 8,000 and having two or more isocyanate groups in the molecule include formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ (in the formula, X consists of an amino group, a hydroxyl group, and a carboxyl group) A group having an active hydrogen atom selected from the group; m is 1 or 2; M is Al, Ca, Ti, Cr, Fe, Co, N
a polyvalent metal selected from the group consisting of i, Cu, Zn, Cd, Sn, Ba and Pb; f is a number equal to the valence of metal M; n is a positive integer from 1 to f). The carboxylic acid metal salt is expressed by the following formula: isocyanate index isocyanate index = (number of isocyanate group equivalents/number of active functional group equivalents of carboxylic acid metal salt) x 100 at a blending ratio of greater than 100 and within the range of 2000 or less A polyisocyanate dispersion composition for polyurethane and polyurea, in which the average particle size of the dispersoid obtained by dispersion is 0.01 to 20μ. (2) The composition according to claim 1, wherein the average particle diameter of the dispersoid is 0.01 to 5 μm. (3) The composition according to claim 1, having an isocyanate index of 200 to 1000.