JPH0723419B2 - Polyether-based polyisocyanate composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a novel polyether-based polyisocyanate composition used as a raw material for the production of polyurethane-based foaming materials, coating materials, adhesives, casting resins and the like. It is a thing.

[Conventional technology]

Heretofore, it has been known that aliphatic polyisocyanate can be used as a raw material for a non-yellowing type polyurethane resin having excellent weather resistance. Typical products of these non-yellowing polyisocyanates include hexamethylene diisocyanate (hereinafter referred to as HMDI), 2,2,4- (or 2,4,4-) trimethylhexamethylene diisocyanate, isophorone diisocyanate (hereinafter referred to as IPDI), etc. There are such diisocyanate monomers, but since these have a relatively high vapor pressure at room temperature, their irritation and toxicity due to inhalation pose problems. Therefore, commonly used aliphatic polyisocyanates are HMDI and
Trimerization of IPDI, etc. with an adduct obtained by reacting with a diol such as butanediol or a triol such as trimethylolpropane, or with a burette obtained by reacting with a buretizing agent such as water or tertiary butanol, or a catalyst. The resulting isocyanurate body is oligomerized and unreacted monomers are removed to reduce the vapor pressure.

These aliphatic polyisocyanate oligomers generally have an average molecular weight of about 600 to 1500 and an NCO content of about 11 to 24% by weight, and are used as a curing agent for paints in combination with a main agent such as bulk polyols. There is.

On the other hand, in the polyurethane resin field, it is not limited to such a curing agent for paints, and for example, in the fields of foaming materials, adhesives, moisture-curing paints, etc., those with a larger average molecular weight, compatibility and workability (for example, with other resins). Often, NCO-terminated polyether urethane prepolymers with improved physical properties such as the mixing characteristics of, the mixing ratio with polyhole, etc. are required,
In addition, the demand for non-yellowing is increasing in such fields.

As such a polyether-based polyisocyanate, one obtained by reacting a diisocyanate monomer such as HMDI or IPDI with a polyetherdiol or triol having a relatively large molecular weight, or an oligomer of the diisocyanate and a polyetherdiol are reacted. There is something.

[Problems to be solved by the invention]

However, in the combination of diisocyanate monomer, diol and triol, it is possible to freely obtain the desired viscosity, physical properties such as NCO content, number of functional groups, molecular weight, etc., depending on the purpose, but the diisocyanate monomer in the reaction product. Inevitably remains, and its use is restricted due to its irritation and toxicity.

On the other hand, reaction products of oligomers such as adducts, burettes, and isocyanurates with polymeric diols alleviate the above-mentioned problem of toxicity of diisocyanate monomers, but oligomers contain 4 or more molecules per molecule. NCO
It is difficult to obtain a polyisocyanate with physical properties according to the purpose because it is very easy to gel during the production of polyisocyanate, and the viscosity is too high even if it does not cause gelation because there are many multimers having groups. Has the drawback that

Therefore, in the art, the appearance of a non-yellowing polyisocyanate having no problem of irritation and toxicity of diisocyanate monomer and capable of freely selecting physical properties according to the purpose has been awaited.

It is an object of the present invention to provide a novel polyether polyisocyanate that can meet such requirements.

[Means for solving problems]

As a result of earnest research to solve the above problems, the present inventors have
It has been found that the object can be achieved by a polyether-based polyisocyanate composition containing a reaction product of 1,8-diisocyanato-4-isocyanatomethyloctane and a bifunctional polyether diol, and the present invention has been completed. .

That is, the present invention comprises 1,8-diisocyanato-4-isocyanatomethylocta and a bifunctional polyether diol having a number average molecular weight of 200 to 10,000 in an NCO / OH equivalent ratio of 3 to
The following general formula (I) obtained by reacting at 20
The present invention relates to a polyether type polyisocyanate composition containing a compound represented by

[In the general formula (I), R ¹ , R ² and R ³ each independently represent the following general formula (2) or —NCO, and at least one of R ¹ , R ² and R ³ is a general formula ( It has the structure of 2), (In the general formula (2), R ⁴ and R ⁵ each independently represent the following general formula (3) or —NCO, Further, Z in the general formulas (2) and (3) is a formula Q is a number average molecular weight of 200 to 10,000
It represents a residue obtained by removing both terminal hydroxyl groups from the polyether diol of 0. ] The polyether-based polyisocyanate composition of the present invention,
It is produced by reacting 1,8-diisocyanato-4-isocyanatomethyloctane with a bifunctional polyether diol having a number average molecular weight of 200 to 10,000.

1,8-diisocyanato-4-isocyanatomethyloctane is used as disclosed in, for example, JP-A-56-127341.
It can be obtained by reacting 8-diamino-4-aminomethyloctane or a salt thereof with phosgene.

As the bifunctional polyether diol, for example, ordinary polypropylene glycol, polyethylene glycol, polytetramethylene glycol or polypropylene glycol to which ethylene oxide is added to the terminal, and further, a special diol such as bisphenol A is used as an initiator to improve physical properties. An improved polypropylene glycol or polyethylene glycol having a number average molecular weight of 200 to 10,000 can be mentioned. These may be used as a mixture if necessary.

If the number average molecular weight of the polyether diol is less than 200, gelation is likely to occur in the polyisocyanate production process, and if it is greater than 10,000, defects in the viscosity of the product and compatibility with other resins may occur. Not preferable.

The reaction is generally carried out at room temperature to 180 ° C, preferably 60 to 140 ° C. If the reaction temperature is too low, it will take a long time to complete the reaction, and if the reaction temperature is too high, side reactions will be generated, which is not preferable. During the reaction, if necessary, aromatic hydrocarbons such as benzene, toluene, xylene, butyl acetate, ethyl acetate, esters such as ethylene glycol monoethyl ether acetate, 2-butanone,
An inert solvent such as ketones such as 4-methyl-2-pentanone or a reaction accelerating catalyst such as a tin compound or a tertiary amine compound can be used.

The charging ratio of 1,8-diisocyanato-4-isocyanatomethyloctane and polyether diol used in the reaction has a great influence on the physical properties of the polyether-based polyisocyanate composition to be formed, and thus it is necessary to carefully select it according to the purpose. However, the equivalent ratio of NCO / OH is selected from 3 to 20.
The smaller the NCO / OH equivalent ratio, the higher the average molecular weight and viscosity of the prepolymer produced, and the lower the NCO content. When this molar ratio is less than 3, gelation is likely to occur in the production process, and when it exceeds 20, the effect of modifying 1,8-diisocyanato-4-isocyanatomethyloctane is poor.

The polyether-based polyisocyanate composition thus obtained is composed of the compound group represented by the general formula (1) and optionally a further polymerized compound and unreacted 1,8-diisocyanato-4-isocyanate. A polyisocyanate mixture that may include natomethyloctane. Further, if desired, it can be used by mixing with an existing polyisocyanate compound such as the above-mentioned adduct body such as HMDI or IPDI, burette body, isocyanurate body or the like.

Although the polyether-based polyisocyanate composition in the present invention is a non-yellowing type that is stable against heat and light, since it does not contain a relatively high diisocyanate monomer such as HMDI or IPDI, it has a pungent odor or There is no risk of toxicity by inhalation, and the molecular weight, viscosity, NCO content, compatibility with other resins, mixing characteristics, and blending can be achieved by selecting the structure and molecular weight of the polyether diol and the NCO / OH equivalent ratio during production. It is possible to freely express the physical properties such as ratio, curing characteristics, etc., and hardness, strength / elongation, flexibility, adhesion to the base material, etc. of the polyurethane resin after compounding with the polyol according to the purpose. .

The polyether-based polyisocyanate composition of the present invention is used as an isocyanate component of a two-component curable non-yellowing polyurethane resin and as a one-component non-yellowing moisture-curable resin.

When used as an isocyanate component of a two-component polyurethane resin, for example, an acrylic polyol, a polyester polyol, a polyether polyol, a terminal hydroxylated polyolefin polyol and a hydrogenated product thereof,
Resins with two or more hydroxyl groups in one molecule such as epoxy-based polyols and polycarbonate-based polyols, and 3,3 '
-Curing in combination with polyvalent active hydrogen compounds such as polyamines such as dichloro-4,4'-diaminodiphenylmethane and its modifications. The resulting polyurethane resin can be used in a wide variety of applications such as foams, casting resins, adhesives, paints, sealants, flooring materials, elastomers and coating agents.

NC when using the polyether-based polyisocyanate composition part of the present invention as a one-pack yellow-free moisture curable resin
A relatively low O content of 12% by weight or less is effective. Such a polyether polyisocyanate composition having a low NCO content comprises 1,8-diisocyanato-4-isocyanatomethyloctane and a polyether polyol having a molecular weight of 200 to 10,000 at an NCO / OH equivalent ratio of about 3 to 4.25. Obtained by reacting.

The obtained polyisocyanate composition is used in the field of paints, adhesives, flooring materials, sealants, coating agents, etc. by adding a catalyst, a pigment and other additives as needed in a solventless system or a solvent dilution system. It is useful as a one-pack type moisture curable resin.

The present invention will be specifically described below with reference to examples. The measuring instruments and measuring methods used in the examples are as follows.

(Measurement equipment) Viscosity: Emila rotational viscometer Infrared absorption spectrum (IR): JASCO Corporation IR-
1 Gel Permeation Chromatography (GPC): Shimadzu LC-3A (Column HSG-40 + HSG-20)
+ HSG-15) (Measurement method) NCO content: Performed according to JIS K-1556.

Average molecular weight: Calculated from the GPC calibration curve based on polystyrene standards.

Physical properties of coating film: Performed according to JIS K-5400.

Example 1 200 g of bifunctional polypropylene glycol having a molecular weight of 1000
To 100 g of 1,8-diisocyanato-4-isocyanatomethyloctane was added 0.002 g of dibutyltin dilaurate as a catalyst, and the mixture was reacted at 100 ° C. for 4 hours. (NCO / OH equivalent ratio = 3) 25 of the obtained polyether-based polyisocyanate composition
The viscosity at ℃ was 7,000 cps and the NCO content was 11.2% by weight.

According to GPC analysis, this was composed of 9% by weight of 1,8-diisocyanato-4-isocyanatomethyloctane and 91% by weight of a high molecular weight substance having a molecular weight of 1000 or more, and the weight average molecular weight of the entire polyisocyanate composition was 7,000, Average molecular weight is 12
It was 00.

Among the high molecular weight compounds, the one with the lowest molecular weight has a molecular weight of about 1500 from the GPC calibration curve, and R ¹ in the general formula (1)
Two are -N = C = O groups of R ^2, R ^3, 1 single but a general formula (2), and R ^4, R ⁵ is -N = C = O group, Q is a polypropylene glycol having a molecular weight of 1000 The molecular weight of something
It showed a good agreement with 1502.

The obtained from infrared absorption spectrum analysis of the polyether-based polyisocyanate composition NCO groups absorption at 2240 cm ^-1, a urethane group absorption at 1710 cm ^-1, characteristic absorption of ether absorption in 1100 cm ^-1 is observed, GPC Together with the result of
It was confirmed to have the structure of the general formula (1).

This product had no odor at room temperature and could be safely handled.

FIG. 1 shows the GPC elution curve of this polyether polyisocyanate composition, and FIG. 2 shows the infrared absorption spectrum.

Examples 2 to 7 The results of the reaction and analysis performed in the same manner as in Example 1 are shown below.
Shown in the table.

The resulting polyether-based polyisocyanate composition,
As in Example 1, it contained a high molecular weight compound by GPC analysis. The molecular weight of the lowest molecular weight compound among the high molecular weight compounds was 1,8-diisocyanato-4-isocyanatomethyloctane at both ends of the polyether diol used. Shows a good agreement with the ones added by urethane bond one by one,
And 2240 cm ^-1 , 1710 cm ^-1 , 1100 cm by IR spectrum
^Since the absorption of ^-1 was observed, it was confirmed that the polyether-based polyisocyanate composition corresponds to the general formula (1).

Comparative Example 1 In place of 100 g of 1,8-diisocyanato-4-isocyanatomethyloctane, HMDI burette (NCO content = 23.3
%, The viscosity at 25 ° C. was 1900 cp) and the reaction was performed in the same manner as in Example 1 except that 216 g was used.

This system has an NCO / OH equivalent ratio = 3 as in Example 1, but 100
When heated at 0 ° C for 1 hour, gelation occurred.

Comparative Example 2 Example 1 except that 100 g of HMDI was used in place of 100 g of 1,8-diisocyanato-4-isocyanatomethyloctane.
The reaction was performed in the same manner as in.

The polyisocyanate obtained had a viscosity of 2800 at 25 ° C.
The cp and NCO contents were 11.1% by weight. This product contained 14.2% by weight of free HMDI and had a strong pungent odor.

Application Example 1 The polyether-based polyisocyanate composition obtained in Example 2 and an acrylic polyol (Acridic A-801:
(Manufactured by Dainippon Ink and Chemicals, Inc.) was blended in an NCO / OH equivalent ratio of 1.0 (A-801 / polyisocyanate weight ratio = 4.3 / 1), and as a thinner, ethyl acetate / toluene / butyl acetate / xylene / cello-solute acetate Ratio = 30/30/20/15 /
Add the mixed solution of 5) and use Ford Cup # 4 for 20 seconds / 20 ℃.
Was prepared. Apply the resulting coating solution with an air spray gun to a dry film thickness of 50μ and apply 10 ° C at 20 ° C / 65% RH.
The physical properties after leaving for a day were measured.

The obtained polyurethane resin coating material had excellent performance as shown in Table 2.

Application Example 2 To 100 g of the polyether type polyisocyanate composition obtained in Example 4, 0.1 g of dibutyltin dilaurate was added, diluted with a thinner and coated. The coating film obtained is 20 ℃ / 65RH%
The composition was moisture-cured within 20 hours under the following conditions, and the physical properties after standing for 10 days under the same conditions were excellent as shown in Table 2.

Comparative Application Example 1 1,8-Diisocyanato-4-isocyanatomethyloctane and acrylic polyol (Acridic A-801) were mixed with N
A CO / OH equivalent ratio of 1.0 was compounded (A-801 / polyisocyanate weight ratio = 13.3 / 1), and coating was performed in the same manner as in Application Example 1 below, and the physical properties were measured.

The obtained polyurethane resin coating film had a defect in flexibility as shown in Table 2.

Application Example 3 The polyether-based polyisocyanate composition obtained in Example 3 and polypropylene glycol having a molecular weight of 2000 and a hydroxyl value of 56 were blended in an NCO / OH equivalent ratio of 1.0, and the mixture was placed in an upper open mold at 80 ° C. for 20 minutes. The polyurethane resin was molded by heating and curing. The polyisocyanate composition and polypropylene glycol were uniformly compatible with each other, and the obtained polyurea resin was also colorless and transparent.

Comparative Application Example 2 A polyurethane resin was obtained in the same manner as in Application Example 3, except that the HMDI burette used in Comparative Example 1 was used in place of the polyether-based polyisocyanate composition of Example 3. The HMDI burette body and polypropylene glycol were not uniformly compatible, and the obtained polyurethane resin was also cloudy and opaque.

[Brief description of drawings]

FIG. 1 shows the infrared absorption spectrum of the polyether polyisocyanate composition obtained in Example 1, and FIG. 2 shows its GPC elution curve.

Claims (1)

[Claims] 1. Obtained by reacting 1,8-diisocyanato-4-isocyanatomethylocta with a bifunctional polyether diol having a number average molecular weight of 200 to 10,000 at an NCO / OH equivalent ratio of 3 to 20. And a compound represented by the following general formula (I). [In the general formula (I), R ¹ , R ² and R ³ each independently represent the following general formula (2) or —NCO, and at least one of R ¹ , R ² and R ³ is a general formula ( It has the structure of 2), (In the general formula (2), R ⁴ and R ⁵ each independently represent the following general formula (3) or —NCO, Further, Z in the general formulas (2) and (3) is a formula Q is a number average molecular weight of 200 to 10,000
It shows a residue obtained by removing both unterminated hydroxyl groups from the polyether diol of 0. ]