JPH10195161A - Molded polyurethaneurea product and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-modulus high-tensile-strength segmented polyurethane urea(SPU) product and a method for preparing this product. SOLUTION: This product is made from a segmented polyurethaneurea(SPU) composed of a segment (1) consisting of a reaction product of an at least difunctional isocyanate compound with a polyol compound having a number- average molecular weight of 800-6,000 and a segment (2) consisting of an isocyanate compound and a diamine compound and having a purity of 80mol% or above and a branching density of 15-50mmol/kg and having such a morphological structure that 10-80%, based on the total area, relatively high-modulus island-like domains are distributed per 9(μm)<2> when an arbitrary surface or cross-section of the product is measured with the viscoelastic mode of a scanning probe microscope with a single-crystal silicon antilever (125μm in length, at a frequency of 7-8kHz and a horizontal resolution of 0.2-1nm) having a spring constant of 0.1-1N/m.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a segmented polyurethane urea molded product having excellent properties (hereinafter referred to as SP).
U-shaped body) and a method for producing the same.
More specifically, the present invention relates to an SPU molding which can exhibit high elongation and high strength without impairing the modulus, while the relationship between the high elongation and the modulus of the SPU molded product obtained by the conventional method was contrary. The present invention relates to a body and a method for producing the same.

[0002]

2. Description of the Related Art Generally, an SPU molded product is prepared by synthesizing a terminal isocyanate prepolymer from a polymer diol and a diisocyanate in a solvent such as N, N-dimethylformamide (DMF) or N, N-dimethylacetamide (DMAc). This is reacted with a diamine compound as a chain extender to increase the molecular weight, and the obtained polymer solution is obtained by desolvation by dry molding or wet molding.

[0003] The main reasons for the need for a solvent are: (1) Since the SPU molded body does not exhibit thermoplasticity, it must be molded from the SPU solution using a method such as dry spinning or wet spinning; 2) The reaction between the terminal isocyanate prepolymer and the diamine compound is very fast, and unless a solvent is used, the reactive groups react before they are uniformly dispersed in the solution, so that only a polymer having a nonuniform polymerization degree can be obtained. Not that. Since a molded product such as a film or a filament is produced using this SPU solution, the primary structure of the SPU is often limited to a solvent-soluble one. On the other hand, attempts have been made to directly obtain SPU without a solvent or with a small amount of a solvent by slowing the reaction between the terminal isocyanate prepolymer and the diamine compound.

For example, it has long been known that the capping of an amine compound with a ketone compound can delay the reaction with an isocyanate group in the terminal isocyanate prepolymer. Use cases exist. For example, JP-A-60-161417 discloses a moisture-curable composition comprising a ketoimine compound, which is a reaction product of an amine compound and a ketone compound, and an isocyanate compound. It has a curing time (pot life), but absorbs moisture by painting to form a cured film. Also, JP-A-53-2439
Japanese Patent Application Laid-Open No. 6-26131 discloses a method for controlling the reaction between a ketoimine compound or an aldimine compound and an isocyanate group at a rate suitable for coating by actively adding water to the reaction system.

In any of these cases, when a ketoimine compound or an aldimine compound is actively formed and an amino group is regenerated from the compound, the amino group is removed by water in the air or aggressively adding water. A method of adjusting the apparent reaction rate with an isocyanate group is employed. However, in these methods, a ketoimine compound or an aldimine compound (also called a Schiff base) is present throughout the reaction, thereby promoting not only the reaction between the isocyanate group and water but also an unknown side reaction. I understood that. Although the cause has not been fully elucidated,
According to common knowledge in the polyurethane chemistry, it is presumed that these basic substances probably act as side reaction promoting catalysts.

[0006] Even more unfavorably, these side reactions accelerate the apparent reaction rate between the isocyanate groups and the amino groups, and the viscosity of the liquid mixture increases rapidly in the mixer. Unevenness of the reaction is caused, and thus, the physical properties of the obtained molded product are liable to fluctuate due to either of these by-products themselves or non-uniformity of polymerization, and their average physical property values are low and continuous. However, it was not satisfactory as a method for manufacturing a compact.

On the other hand, JP-A-63-154719 and JP-A-1-210416 disclose that by adding a polymer diol to a mixture of ethylenediamine and acetone, the viscosity of the compound is reduced to that of a terminal isocyanate prepolymer. A method has been shown in which the temperature of the mixing is reduced to 35 ° C. or lower to delay and suppress the reaction during the mixing, thereby facilitating the mixing of the two and continuously forming a thick filament or the like without a solvent. . However, the terminal isocyanate prepolymers described in these examples coagulate at about 20 ° C., so there is a limit to lowering the mixing temperature, and the reaction of the mixed solution cannot be sufficiently suppressed. Stable mixed molding is difficult. In addition, unevenness in the physical properties of the molded article caused by a decrease in the mixing property cannot be avoided. Furthermore, the poor compatibility of the thickener added to the ketoimine compound with the ketoimine compound also causes a decrease in the miscibility with the terminal isocyanate prepolymer, leading to uneven physical properties.

Further, a method of molding a thermosetting polyurethane and / or polyurethane urea sheet without using a solvent is disclosed in JP-A-62-191119. That is, when a thermosetting polyurethane and / or polyurethane urea sheet is produced by an extrusion coating method, the raw material is cast while the extrusion head is cooled to 30 ° C. or lower, and then heated and cured to produce a sheet. . However, with a method that only cools the extrusion head,
It is effective for molding a polyurethane elastic body obtained by reacting a compound having a hydroxyl group, but for the reaction between an amino compound and an isocyanate compound as in the present invention,
Since the reaction between the two is remarkably fast, it is insufficient to perform uniform curing and obtain a homogeneous molded product. In addition, the adhesion of the raw material and the molded product to the inside of the die cannot be prevented, and the adhered raw material and the molded product cause a curing reaction, gradually closing the inside of the die and increasing the pressure, making it difficult to manufacture for a long time. .

Further, the present inventors have disclosed a Japanese Patent Application No. 6-160.
No. 763 proposes a reaction molding method for a continuous SPU molded article using an amine compound having an asymmetric structure. However, even when this method was used, the viscosity difference between the diamine composition and the terminal isocyanate prepolymer was large, so that the mixing at the time of mixing the two liquids was insufficient, and it was found that unevenness in the physical properties of the molded article was inevitable. . In the method described above, it is difficult to adjust the viscosity of the two liquids to be mixed, and if the cooling is performed so that the coagulation of the terminal isocyanate prepolymer does not start, the viscosity of the mixed liquid in the mixer rapidly increases. Only the SPU molded article having the variance in physical properties was obtained.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a conventional SPU molded article produced without a solvent (or in a small amount of a solvent) and an SPU molded article obtained by solution polymerization which is a general SPU molding method. It is an object of the present invention to provide an SPU molded article exhibiting a high modulus in spite of high elongation and high strength and having significantly improved unevenness in physical properties, and a method for producing the same.

[0011]

That is, the present invention relates to a bifunctional or more functional isocyanate compound and a compound having a number average molecular weight of 800.
Of a segmented polyurethane urea molded product comprising a segment (1) having a reaction product of a polyol compound of from 6000 to 6000 as a component and a segment (2) having a reaction product of the isocyanate compound and a diamine compound as a component. Among them, the purity X (the ratio of the segment (2) to the total urea groups) of the segment (2) in the polymer shown in the following formula is 80 mol% or more, and 15 to 5
A segmented polyurethane urea molded article having a branch density of 0 mmol / kg, wherein any surface or cross section of the molded article is subjected to viscoelastic mode of a scanning probe microscope,
When measured with a single-crystal silicon cantilever (length: 125 μm, frequency: 7 to 8 kHz, horizontal resolution: 0.2 to 1 nm) having a spring constant of 0.1 to 1 N / m, it is relatively within 9 (μm) ^2. 10 high-modulus island domains in total area
This is achieved by a segmented polyurethane urea molding having a high strength elongation and a high modulus characterized by having a morphological structure distributed at a rate of 〜80%.

X = ｛[Urea (1)] / ([Urea (1)
(1)] + [Urea (2)]) × 100 where [Urea (1)] is the integral intensity of ureacarbonyl carbon of segment (2) determined by ¹³ C-NMR method, and [Urea ( 2)] represents the integrated intensity of the carbonyl carbon of the urea group generated by the reaction between the isocyanate group and water. That is, X represents the mole fraction of urea groups resulting from the main reaction relative to the total amount of urea groups resulting from the main reaction and side reactions.

When the purity X of the segment (2) is less than 80 mol%, bubbles of carbon dioxide generated by the reaction between the isocyanate group and water, which are side reactions, remain in the molded product,
Not only the breaking elongation at break is remarkably reduced, but also the step (2) of the production method as described below, that is, a composition (A) comprising a diamine compound / ketone compound or an aldehyde compound and a terminal isocyanate prepolymer composition (B) When the precursor (I) is mixed with the precursor (I), blockage is caused in the mixer, which causes uneven mixing and consequently causes unevenness of physical properties.

The unevenness of the physical properties of the SPU molded product obtained in the present invention is remarkably improved because side reactions are suppressed and the polymerization rate is controlled. In addition, although the SPU is insoluble in a solvent, it cannot be polymerized by the conventional solution method, although the primary composition (chemical structure) is expected to have higher physical properties (improvement of elastic properties, etc.). In addition, a segment (2) high-content SPU molded article and the like are also included.

The SPU molded article of the present invention additionally has the following three features. That is, (A) high segment (2) content, (B) moderate branch density, and (C)
The main feature is a sea-island-like phase-separated solid structure. Surprisingly, due to these characteristic structures, the physical properties of the SPU molded body exhibit high elongation, high strength, and high stress, and exhibit well-balanced physical properties. This can dispel the common sense up to now, that is, the trade-off relationship between high elongation and modulus.

If the branch density is less than 15 mmol / kg, the modulus of elasticity of the molded article is extremely reduced. On the other hand, 50mmo
If it exceeds 1 / kg, the elongation of the molded body may be reduced, and the frequency of branch formation in the mixer may increase, resulting in blockage in the mixer. The SPU molded article of the present invention is characterized in that the surface or cross section of the molded article exhibits a viscoelastic sea-island-like phase-separated solid structure. The existence of such a unique phase-separated solid structure can be known by observing the surface or cross section of the molded body in a viscoelastic mode of a scanning probe microscope. The observation principle and analytical considerations are described in Biophysics Journal.
1, 64 volumes, p. 735 (1993).

The SPU molded article of the present invention is a single-crystal silicon cantilever having a spring constant of 0.1 to 1 N / m (length: 125 μm, frequency: viscoelastic mode of a scanning probe microscope). (7-8 kHz, horizontal resolution 0.2-1 nm), the molding selected by paying attention to the correlation between the ratio of the domain having a relatively high elastic modulus in the observed viscoelastic distribution structure and the mechanical properties. Body. That is, the SPU molded article of the present invention has a sea-island-like phase-separated solid structure, and has a total area ratio of relatively high elastic islands per 9 (μm) ² of 10 to 80%. is there. If this value is less than 10%, the breaking strength of the molded article is sharply reduced, while if it exceeds 80%, the elastic function is significantly reduced, and the breaking elongation is also extremely reduced, which is not preferable.

The SPU film of the present invention has a thickness of 1
0 to 1000 microns, and the fiber has a single yarn fineness of 10
0 to 6000d. The mechanical properties of the fiber are 300
% Stress is 0.05 to 0.50 g / d and breaking strength is 1.4.
-1.6 g / d, elongation at break of 780-950%, and excellent balance of physical properties that have never existed before. The SPU molded article having a high modulus of the present invention is:
Basically, it can be manufactured by a method including the following steps.

(1) A diamine compound represented by the following general formula [1] and at least one compound selected from the group consisting of a ketone compound and an aldehyde compound represented by the following general formula [2] have a molar ratio of 1/1. React at ~ 1/10,
The imidazolidine compound represented by the following general formula [3] is added in an amount of 40 to the charged molar amount (M _DA ) of the diamine compound.
Preparing a composition (A) containing at least 30 mol% and 30 to 2000 mol% of water; (2) a viscosity at 25 ° C. of 0.5 to 1000 Pa with the composition (A);
The ratio (R) of the molar amount of isocyanate groups of the composition (B) / the molar amount of amino groups of the diamine (2M _DA ) (R) is 1 <R. as a ≦ 1.5, yet mixed in the presence of 0.001 to 10 mol% of the acid compound relative to M _DA, molded into precursor molded bodies (I) step,
(4) a step of polymerizing the precursor molded article (I) in a heated atmosphere to obtain a precursor molded article (II); and (5) an annealing treatment of the precursor molded article (II).

[0020]

Embedded image (However, R represents a group selected from an aliphatic or alicyclic hydrocarbon having 1 to 10 carbon atoms.)

[0021]

Embedded image (However, R ₁ and R ₂ are selected from hydrogen or a hydrocarbon group having 1 to 10 carbon atoms and may be different from each other, except that both are hydrogen. In addition, R ₁ and R ₂ are linked to each other. Including those forming a cyclic group.)

[0022]

Embedded image (However, R represents a group selected from an aliphatic or alicyclic hydrocarbon having 1 to 10 carbon atoms. R ₁ and R ₂ are selected from hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and They may be different, except that both are hydrogen, and also include those in which R ₁ and R ₂ are linked to form a cyclic group.) The molded article can be a film or a fiber.

In the present invention, the reaction mixture of the diamine compound and the carbonyl compound (composition (A)) is not a product containing a ketoimine (aldoimine) compound as a main product as in the conventional method, but is an isomer, imidazo. Based on the finding that the lysine compound is extremely stably present in the reaction system, a certain molar amount of the imidazolidine compound is used to adjust the viscosity of the terminal isocyanate prepolymer (composition (B)). By mixing the molar amount of the isocyanate group contained in B) in a slightly excessive state with respect to the molar amount of the amino group (2M _DA ) of the charged diamine compound contained in the composition (A), uniform mixing with the diamine compound is achieved. Sex became possible for the first time. As a result, since there are few side reactions and an optimal reaction rate and viscosity for performing continuous polymerization molding, mixing unevenness is unlikely to occur, and thus it is possible to make the fluctuation of the physical properties of the obtained SPU molded article extremely small. did it. Further, the physical properties of the molded product are further improved by the branching reaction during the polymerization reaction by the reactive isocyanate group and / or during the annealing treatment after the completion of the polymerization reaction, as compared with the conventional method.

The diamine compound used in the present invention is a diamine compound represented by the general formula [1].

As specific examples, ethylenediamine,
1,2-propylenediamine, 1,3-propylenediamine, 1,2-butylenediamine, 1,3-butylenediamine, 1,4-butylenediamine, 1,5-hexanediamine, isobutylenediamine, 1,6-hexane Diamine, cyclohexanediamine, isophoronediamine and the like can be mentioned. A diamine compound having high symmetry, such as ethylenediamine, is more preferable from the viewpoints of securing an optimal polymerization reaction rate for reaction molding and mechanical properties of the obtained SPU molded article.

Specific examples of the ketone compound and / or aldehyde compound represented by the general formula [2] used in the present invention include acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, acetophenone. Benzophenone, acetaldehyde, butyraldehyde, benzaldehyde and the like. Of these, aliphatic ketones are preferred, and specific compounds include acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, and the like.

Next, the composition (A) obtained by reacting the diamine compound with the carbonyl compound will be described. The composition (A) contains the imidazolidine compound represented by the general formula [3] in a molar fraction of 40 mol% or more based on the molar amount (M _DA ) of the diamine compound used.

As described above, the content of the imidazolidine compound represented by the general formula [3] in the reaction composition (A) is determined for the purpose of exhibiting the high physical properties of the SPU molded product and for the urea formation reaction by the isocyanate group and the amino group. It is important to control the speed and needs to be within the above range. When the amount of the imidazolidine compound is less than 40 mol% (relative to M _DA ), it means that the amount of the diamine compound or ketoimine and / or aldimine is large. Only coalescence is obtained, and if the amount of ketoimine is too large, the amount of by-products increases as described above, and the apparent polymerization rate is also accelerated, which is not preferable.

As can be seen from the results of the examples described later, in the present invention, in a system in which the imidazolidine compound, which is an isomer, is present in an amount larger than a certain amount, the amount of by-products in the obtained SPU molded product is less than a certain amount. It has been found that the physical property values of the SPU molded product and their balance are much better than those of the SPU molded product obtained by the conventional method.
From this, although there is no particular problem even if the amount of the imidazolidine compound is too large, the range of 40 to 95 mol% (relative to M _DA ) is preferable.

In order for the imidazolidine compound to be present in the above-mentioned range, the molar ratio of the diamine compound and the carbonyl compound depends on the chemical structure of the diamine compound and the carbonyl compound and the reaction temperature and the reaction time. The reaction must be carried out in a range of ratios, and the preferred molar ratio for producing more imidazolidine compound is in the range of 1 / 1.5 to 1/5. The reaction temperature and time also depend on the chemical structure of both, but the conditions under which the composition (A) falls within the range of the present invention are respectively 0 to 80 ° C and 10 minutes to 10 hours, preferably 30 to 60 ° C, respectively. And 1-3 hours.

Water is formed simultaneously with the imidazolidine and ketoimine (or aldimine) compounds by the condensation reaction of the aliphatic diamine compound and the carbonyl compound in the composition (A). In order to control the amount of the diamine compound and the imine compound, that is, to control the polymerization rate and suppress the side reaction, it is essential in the present invention that the compound is further intentionally added to the system. 30 for the preferred amount of water is M _DA for the
~ 200 mol%. More or less than this, the content of the imidazolidine compound does not satisfy the desired value. When water is intentionally added in this way, it may be added at any time during or after the reaction of the aliphatic diamine compound and the carbonyl compound, but in the latter case, the equilibrium composition is reached. It is necessary to further react until.

The composition (B) mixed with the composition (A) in the step (2) in the present invention is a terminal isocyanate prepolymer having two or more functional groups (hereinafter referred to as a terminal isocyanate prepolymer). The terminal isocyanate prepolymer is synthesized by a conventional method by reacting a polyol compound with a difunctional or higher functional isocyanate compound. The polyol compound is a polyether polyol, a polyester polyol, a polylactone polyol, or a polycarbonate polyol having a number average molecular weight in the range of 800 to 6000, preferably 1,000 to 3,000, and a melting point of 60 ° C. or less. Further, a polyol compound such as polydimethylsiloxane diol is also included. With a polyol having a number-average molecular weight of less than 800, the resulting SPU molded article has low elongation, the characteristics of high elongation and high recovery as an SPU molded article cannot be utilized, and structural destruction at the time of elongation is remarkable. The permanent set increases. Conversely, in a polyol having a number average molecular weight exceeding 6000, the resulting SPU
The molded article has a low elastic modulus. The use of a polyol having a high melting point is not preferred because the recovery of the molded article is low and the viscosity of the terminal isocyanate prepolymer increases.

Examples of the polyether polyol include polyoxytetramethylene glycol (PTMG), poly (1,5-pentanediol), polyethylene glycol and the like. As the polyester polyol, oxalic acid, succinic acid, glutaric acid, fumaric acid, sebacic acid, maleic acid, itaconic acid, adipic acid, a mixture of two or more dibasic acids such as malonic acid, ethylene glycol, propylene Glycol, butanediol, hexamethylene glycol, those obtained from one or more diols such as cyclohexane dimethanol, and polyesters having a carboxyl group at the terminal obtained by such a method, for example, It is also possible to use those obtained by further reacting polyether diols such as polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol and polyoxypentamethylene glycol.

Examples of the polylactone polyol include those obtained by reacting a hydroxycarboxylic acid obtained by ring-opening polymerization of ε-caprolactone with a diol such as propylene glycol or butanediol, or polyoxytetramethylene glycol. Examples thereof include those obtained by reacting a polymer diol such as polyoxypentamethylene glycol.

As the polycarbonate polyol, alkylene carbonates and 1,4-butanediol,
Poly (butane-1,4-carbonatediol), poly (pentane-1,3-carbonatediol) obtained by reaction with 1,3-pentanediol, 1,5-pentanediol, 1,6-hexanediol and the like , Poly (pentane-1,5-carbonate diol), poly (hexane-1,6-carbonate diol) and polycarbonate diols obtained from copolymers and mixtures thereof. Among these polyols, polyester polyols and polylactone polyols are easily embrittled, and polycarbonate polyols have high melt viscosity and are difficult to handle. Therefore, polyether polyols are preferable. Among them, polyoxytetramethylene glycol (PTMG) is preferable. Is particularly preferred.

The isocyanate compound includes aliphatic di- and triisocyanates, aromatic di- and triisocyanates. Specific examples of the aliphatic isocyanate include 1,4-tetramethylene diisocyanate,
6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, 1,6,11-undecane triisocyanate, 4-methyl-1,8-octane diisocyanate, 1,3,6-hexamethylene triisocyanate, 3,3-dimethyl Pentane-1,5-diisocyanate and the like. 1,3- and 1,4-
It is also possible to use cycloaliphatic diisocyanates such as cyclohexane diisocyanate.

As the aromatic di- and triisocyanates, it is preferable that the isocyanate group is directly bonded to the benzene nucleus and the two isocyanate groups are bonded to each other at the para position. Even when an aromatic diisocyanate in which two isocyanate groups are bonded at asymmetric positions, for example, 2,4-tolylene diisocyanate or 1,3-phenylene diisocyanate, a uniform SPU molded product can be obtained. However, it is not preferable because the physical properties of the molded article are inferior to those of the para-linked aromatic diisocyanate. Such aromatic diisocyanates include 1,4-
Phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diphenyl ether diisocyanate, 1,5-naphthalene diisocyanate, 2,6-naphthalene diisocyanate,
Trizine diisocyanate, m- and p-xylylene diisocyanate, and α, α, α ′, α′-tetramethyl-p-xylylene diisocyanate. Among these aromatic diisocyanates, 4,4′-diphenylmethane diisocyanate (MDI) is particularly preferred in view of the balance between uniform mixing and physical properties of the SPU molded product. As the aromatic triisocyanate, triphenylmethane triisocyanate, tris (isocyanatephenyl) thiophosphate and the like can be used.

In the present invention, when mixing the composition (A) and the composition (B), it is necessary to add water and an acid compound. Water may be added to the composition (A) in advance, or may be added when both are mixed. The amount of acid added is M _DA
It is 0.001 to 10 mol%, and may be added to the composition (B) in advance, but is preferably added when both are mixed.

As the acid compound, any of an organic acid and an inorganic acid can be used. For example, aliphatic and aromatic carboxylic acids, phosphoric acid, sulfonic acid, boric acid, phosphoric acid ester, borate ester, phosphite ester, sulfurous acid gas, hydrochloric acid, sulfuric acid, nitric acid and the like, especially alkyl phosphoric acid, acetic acid And at least one acid selected from p-toluenesulfonic acid and the like. The addition of the acid accelerates the hydrolysis of the ketoimine or aldoimine compound, thereby suppressing side reactions and controlling the polymerization rate. However, since the acid compound also promotes the hydrolysis reaction of the imidazolidine compound to the diamine compound to a considerable extent,
When it is necessary to obtain an SPU molded article relatively quickly during polymerization, for example, when obtaining a filament by continuous reaction spinning, the range of 0.1 mol% to 5 mol% is preferable.
For curing at a slower rate, for example for films, coatings and lacquers, 0.01
The range of 0.5 mol% is preferable.

In the mixing of the present invention, the polymerization reaction is controlled at a desired rate, but the reaction between the supplied composition (A) and the supplied composition (B) is very small even in the mixer. Inevitably occur. In this case, if the viscosity difference between the compositions (A) and (B) is large, the reaction proceeds before the uniform mixing, and the mixture is discharged as a mixture having uneven viscosity, and the uneven S
It becomes a PU molded body. As a result of intensive studies to improve the unevenness of the physical properties of the SPU molded article caused by this, the viscosity of the composition (B) was adjusted to 0.5 to 5000 Pa · s, and the viscosity difference with the composition (A) was reduced. Uniform mixing was facilitated, and an SPU molded product with significantly improved unevenness in physical properties was obtained. As means for adjusting the viscosity of the composition (B) to a desired viscosity range, (1) reduction of the molecular weight of the terminal isocyanate prepolymer, (2) use of an isocyanate compound having little intermolecular interaction, and (3) composition ( Addition of a viscosity modifier to B).

In order to utilize the method (1), the composition (B)
The object can be achieved by further increasing the equivalent ratio (n value) between the polyisocyanate compound and the polyol compound when synthesizing the polyisocyanate compound, which is higher than 1.4 to 1.8 performed in the usual spandex fiber production. When the isocyanate prepolymer is synthesized with a high n value, the content of the segment (2) in the SPU molded article can be increased, so that a molded article excellent in modulus, breaking strength, and the like can be obtained (Examples). However, if this ratio is too high, the molecular weight of the terminal isocyanate prepolymer is too small, and it takes too much time for heat curing, which is not preferable. Accordingly, the n value is usually preferably in the range of 1.8 to 10, although it depends on the types of the polyol compound and the polyisocyanate compound used.

Incidentally, the content of the segment (2) in the SPU molded article can be increased by further adding an isocyanate compound after the synthesis of the terminal isocyanate prepolymer. The equivalent ratio of the isocyanate compound and the polyol compound to be formed, that is, the n value is preferably in the range of 1.8 to 10. The method (2) is enabled by a combination of raw materials for synthesizing a terminal isocyanate prepolymer. For example, by using dimethylsiloxane diol as a polyol compound, the viscosity of the composition (B) can be adjusted to a desired viscosity as described in Examples.

As the viscosity modifier used for carrying out the method (3), a low-boiling compound capable of dissolving the terminal isocyanate prepolymer can be used. By adding the viscosity modifier, the viscosity of the composition (B) can be reduced to an appropriate value, and it is easy to maintain the mixing property of the compositions (A) and (B) well for a long time. Become. Specifically, ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone,
N, N-dimethylacetamide, tetrahydrofuran,
Dimethyl sulfoxide or the like is used. Of these, acetone is particularly preferred because of its ease of removal during molding.

As a method of further reducing the difference in viscosity between the compositions (A) and (B), the viscosity of the composition (B) is reduced to 10 to 2
After adjusting the pressure to 000 Pa · s,
As disclosed in JP-A-154719 and JP-A-1-210416, it is also possible to add a reaction-inactive oligomer or the like to the composition (A) to reduce the difference in viscosity between the two.

The rapid polymerization reaction in the mixer causes a sudden increase in the viscosity of the reaction solution, and deteriorates the mixing properties of the compositions (A) and (B). Therefore, in order to control the polymerization reaction rate, it is necessary to keep the polymerization reaction temperature low. Preferred polymerization temperatures are in the range of -20 to 80C, with 0 to 35C being particularly preferred. If the temperature is higher than 80 ° C., a side reaction proceeds and the viscosity of the mixed solution further increases, which is not preferable. If the temperature is lower than −20 ° C., even if a viscosity modifier is added, the composition (B) is coagulated and may cause uneven mixing, which is not preferable. Usually, an appropriate cooling means such as circulating cooling water around the mixer is provided to adjust the temperature to an appropriate temperature.

As a method for preventing thickening in the mixer, the amount of amino group (2 M) of the charged diamine compound in the composition (A) is used.
_DA ) or an amount of isocyanate groups in the composition (B). As the amino groups of the composition (A) and the isocyanate groups of the composition (B) approach stoichiometric equivalents, the time required for the discharged mixture, that is, the precursor molded article (I), to become tack-free (hereinafter referred to as non- Adhesion time) is shortened. In the case of mixing exceeding the equivalent amount and excess amount of amino group, even if the amount is increased to about 1.5 times the equivalent amount, the non-adhesion time does not largely change, but desired physical properties of the molded article cannot be obtained. On the other hand, when the mixing ratio is such that the isocyanate group is increased, the non-adhesion time of the precursor (I) becomes longer, but a branching reaction occurs during annealing due to the isocyanate group remaining in the precursor molded article (II) after the polymerization reaction. S to do
It was found that the physical properties of the PU molded body were further improved than before. After giving utmost priority to mixing properties and then taking into account the physical properties of the molded product, the amount of isocyanate groups was determined to be the amount of amino groups (2
It is appropriate to mix them within 1.5 times the molar amount with respect to (M _DA ), and preferably 1.1 to 1.3 times. If it is more than 1.5 times, the molecular weight of the SPU molded article does not increase and desired physical properties cannot be obtained.

The compositions (A) and (B) can be mixed with usual additives such as stabilizers and modifiers as long as the effects of the present invention are not impaired. For example, antioxidants such as hindered phenols and hindered amines, pigments, internal release agents such as silicones and fluorines, molecular weight regulators such as diethylamine, surfactants for improving the mixing property, oils, dyeing And the like.

The mixer according to the present invention is a device having a capacity having a supply port for a supply liquid and a discharge port for discharging the mixture, and a device in which mixing is performed in the volume part. As a mixing means, there are mechanical mixing by a stirrer, filling and mixing by a filler known as a static mixer, collision mixing by a jet stream of a supply liquid, and the like.

When a static mixer is used, ultrasonic waves are preferably transmitted to the mixer to prevent the reaction mixture from blocking the mixer. Means for transmitting ultrasonic waves to the mixer include a direct method in which an ultrasonic vibrator is directly attached to the mixing device, and a method in which the vibrator is placed in a medium such as water, silicone oil, lower alcohol, lower glycol, etc. Indirect method of generating ultrasonic waves and propagating ultrasonic waves to the mixer through the medium is possible, but it is necessary to cool the vibrator because it generates heat with vibration. It is desirable to use the latter indirect method in which a mixer is provided to simultaneously cool the mixing device and the vibrator, and furthermore, ultrasonic waves can be transmitted to the mixer with a simple structure.

The frequency of the ultrasonic vibrator used to apply ultrasonic vibration to the mixer varies depending on the type and size of the mixer, the method of transmitting ultrasonic waves to the mixer, and the like.
Usually, the range of 10 to 100 KHz is practical, and if the frequency is less than 10 KHz, it is not preferable in terms of noise. On the other hand, the use of an ultrasonic vibrator having a frequency exceeding 100 KHz requires the use of a mixer in the indirect method via a medium. The transmission of ultrasonic waves to the mixer is weak, a high output is required to prevent clogging by the reaction mixture in the mixer, and electric energy costs increase, which is not preferable. 15 commonly used for emulsification, dispersion, and washing
It is preferable to use an ultrasonic vibrator that generates a high frequency of a frequency of about 50 KHz because it can be obtained at low cost.

FIG. 1 schematically shows an example of a molding process when the SPU molded article of the present invention is a filament. The liquid compositions (A) and (B) are each transferred to a mixer with a stirrer by a pump, mixed in the mixer while being cooled, and discharged in a filament form from a spinning hole (precursor molded body (I)). . The precursor molded article (I) is polymerized while passing through the heating tube, is wound up (precursor molded article (II)), and is subjected to appropriate annealing to obtain the SPU molded article of the present invention. An example describes a method of forming a filament by this process. Alternatively, the precursor (II) can be produced using a dry spinning cylinder for producing spandex as described in, for example, Japanese Patent Publication No. 39-166672. When the precursor (II) is prepared by a wet method, the precursor molded product (I) is prepared by using an apparatus described in JP-B-42-19595.
Is discharged into a heating coagulation bath and reacted to form a precursor (I
Obtain I). If there is no viscosity modifier, the mixture can be discharged directly into the mold. Since the precursor molded article (I) immediately after discharge still has adhesiveness, it is preferable that the surface of the support is release-treated with a release agent such as a silicon-based or fluorine-based substance. Next, heat curing treatment is performed (in some cases, the viscosity modifier is simultaneously removed). As a heating source, heating methods such as infrared rays and far infrared rays other than the above-mentioned hot air or heating coagulation bath can be employed. However, if the heating temperature is too high, the obtained precursor molded body (II) is softened and continuously heated. A molded article cannot be obtained. Conversely, if it is too low, it takes time for polymerization,
Although it depends on the heating method, it is usually preferable to perform the heating in the range of 50 to 250 ° C. The heating time varies depending on the type and composition of the raw materials of the compositions (A) and (B), the mixing conditions, the heating method, the temperature, and the like, and can be determined by measuring the degree of polymerization and physical properties of the SPU molded article.

In the subsequent step (4), in order to obtain an SPU molded article as a final product, an annealing treatment is carried out to carry out a branched crosslinking reaction with unreacted isocyanate groups to deactivate the isocyanate groups in the molded article. The annealing temperature is 70 to 15 as a condition for adjusting the branch density.
0 ° C. and the time are preferably 5 to 50 hours. If the annealing temperature is lower than this, the branching reaction hardly occurs, and
If the temperature is higher than 0 ° C., decomposition of the polymer occurs, which is not preferable.

The SP thus obtained according to the present invention
As described above, the U-shaped body has excellent characteristics that have not been seen before, and can be applied not only to fibers and tapes, but also to films, paints, coatings, and the like.
Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited by these.

[0054]

BEST MODE FOR CARRYING OUT THE INVENTION In the molding method shown in the following examples, mixing unevenness during reaction molding caused by a sudden increase in viscosity due to polymerization or side reaction during mixing of the composition (A) and the composition (B). Mainly adopted a filament forming (reactive spinning) method which can be observed with high sensitivity as unevenness of physical properties, and also tried to partially form a film. In the examples, the chemical composition and physical properties of the SPU molded body were measured according to the methods described below.

(1) Quantification of chemical species contained in composition (A) obtained from diamine compound and carbonyl compound: ¹
It was determined by the H-NMR method. (2) A molar amount (2M _DA ) in terms of amino group of the charged diamine compound in the composition (A) and a molar amount of isocyanate group in the composition (B): A predetermined amount of each of the two compositions was weighed, and 0.1
It was determined by titration using a standard aqueous solution of N hydrochloric acid (indicator: phenolphthalein). The amount of isocyanate groups in the isocyanate prepolymer is determined by S.I. Sigma and
J. G. FIG. Hanna, Anal. Chem. , 20 volumes,
It was determined according to the titration method described on page 1084 (1948).

(3) Number average molecular weight (Mn) of terminal isocyanate prepolymer: After reacting the synthesized terminal isocyanate prepolymer with ethanol, the molecular weight was determined in terms of polystyrene using GPC (gel permeation chromatography). (4) 300% stress, breaking strength, breaking elongation: Using Tensilon UTM-III (manufactured by Toyo Baldwin),
Sample length 50mm, tensile speed 500mm / min, temperature 20 ° C
Was measured.

(5) Segment in SPU molded article (2)
Purity X: The urea group generated from the reaction between the isocyanate group and the amino group is Urea (1), the urea group generated from the reaction between the isocyanate group and water is Urea (2), and Urea (1) and Urea (2) U) in the total amount of
The ratio of the area (1) is defined as the purity X of the segment (2),
^It was determined from the integrated intensity of both ureacarbonyl carbons in ¹³ C-NMR. (6) Unevenness of physical properties: The coefficient of variation of the breaking strength value of the obtained monofilament was defined as unevenness of physical properties, and was obtained as a standard deviation / average value of the breaking strength measured 10 times.

(7) Morphological analysis method of SPU molded body surface by scanning probe microscope (SPM) method: SP
Scan the cross section of the U filament (diameter: 0.5 mm) or the film with a scanning probe microscope (SPM) manufactured by Digital Instruments.
Control station, model Nano Sco
Measured by force modulation using pe III.

The material of the cantilever is single crystal silicon (spring constant 0.18 N / m, length 125 μm, frequency 7 to
8kHz, 20 ° cone angle at tip, radius of curvature about 10n
m), using a scan range of 3000 nm,
The measurement was performed in the atmosphere at a measurement temperature of 298K. The amplitude of the cantilever is a voltage value reflecting the viscoelasticity, and FIGS. 2 and 3 are obtained by imaging the voltage value with light and dark colors. Calculation of the size of the island domain (high elastic modulus domain) having a relatively high elastic modulus and the occupied area in this image is performed by an image analyzer, model I, manufactured by Asahi Kasei Corporation.
Performed using P-1000PC. However, the calculation was performed in the tissue analysis mode by dividing the light and dark portions in the image into 10 equal contrasts and recognizing the portions from the darkest portion to the four contrast portions as high elastic modulus domains.
The average value after five measurements was taken as the final value.

(8) Measurement of branch density of SPU molded article: A 30% by weight N, N-dimethylacetamide solution of the obtained SPU molded article was prepared, and 1% by weight of n-butylamine N, N-dimethylacetamide was added thereto. Add the solution and add 50
C., heat treatment was performed for 4 hours. The remaining n-butylamine was titrated with a 0.1N aqueous hydrochloric acid solution, and the number of moles of n-butylamine consumed per 1 kg of the SPU molded body was expressed as a branch density. When a polyfunctional isocyanate compound was used, the value obtained by subtracting the concentration of the bifunctional isocyanate (ρ) was determined by the following equation, and the value converted to 1 kg of the SPU molded product was added to the branch density determined by the above method.

Ρ = {(f−2) N ₀ } / (fN ₀ + 2L ₀ ) (where f is the number of isocyanate groups of the polyfunctional isocyanate compound, N ₀ is the mole fraction of the polyfunctional isocyanate,
L ₀ is the molar fraction of the bifunctional isocyanate. The measurement method is Polymer Internationala
1, Vol. 31, P131 (1993). )

Example 1 (1) Preparation of Composition (A) by Reaction of Diamine Compound / Carbonyl Compound Diamine compound and carbonyl compound at predetermined molar ratios shown in Table 1 were weighed and mixed at 30 ° C. And stirred for 3 hours. Subsequently, the amount of water shown in Table 1 was added to the amount of amino group (2M _DA ) of the charged diamine compound, and the reaction was further performed for 1 hour. The imidazolidine content (mol%) in the composition (A) was calculated from the methylene peak intensities of unreacted diamine, imidazolidine, and ketoimine compounds in the ¹ H-NMR spectrum.

(2) Preparation of terminal isocyanate prepolymer (composition (B)) 18.0 kg of polyoxytetramethylene glycol (PTMG; number average molecular weight (Mn) 1800) and 4.6
3 kg of 4,4'-diphenylmethane diisocyanate (MDI) was placed in a reactor equipped with a stirrer, and at 80 ° C.
The reaction was performed for 5 hours. Thereafter, 0.88 kg of MDI, the amount of acetic acid (relative to M _DA ) shown in Table 2 and 10 kg of a viscosity modifier (acetone) were added, and after an additional hour of reaction, the amount of isocyanate groups was determined by titration. .72 mol /
kg. Mn was determined by the method described above, and the results are shown in Table 2.

(3) Mixing and molding As shown in FIG. 1, the number of moles of amino groups (2M _DA ) of the amino group of the charged diamine compound in the composition (A) obtained by the reaction of the diamine compound / carbonyl compound and the terminal isocyanate prepolymer The molar ratio of isocyanate groups in the polymer (composition (B)) is 1: 1.2, and the compositions (A) and (B)
Was set so as to be 30 to 70 g / min, and the mixture was continuously and quantitatively supplied to the mixer by a gear pump and extruded from a spinneret having a diameter of 0.5 mm. 10 ° C in the mixing machine
The filament (precursor molded body (I)) cooled and extruded below passes through a heating cylinder having a diameter of 40 cm and a length of 250 cm set at an ambient temperature of 220 ° C.
/ Min at a speed of winder. The temperature of the wound filament (precursor molded body (II)) is 80 ° C
For 10 hours in an oven maintained in a nitrogen atmosphere. The ejection stability of the precursor molded article (I) was determined by the number of yarn breaks per unit time as described in the margin of Table 2. Tables 2 and 3 show the mixing, molding conditions, filament properties and physical properties, respectively.

(4) Surface Morphology of Molded Yarn by SPM Method FIG. 2 shows a typical example of the surface morphology of SPU molded yarn measured in the force modulation mode of the SPM method. A dark part on the image corresponds to a part having a relatively high elastic modulus. The light and dark areas are divided into 10 equal parts by image analysis, and the high elasticity domain is defined from the darkest part to the four contrast parts. Although the high elasticity domain has a wide distribution, the average minor axis is 80 nm and the average major axis is 140 nm.
The total area of the high modulus domain of the ellipse is 22% of the observation range
Occupy.

(Embodiment 2) As shown in (2) of Embodiment 1,
MD added after the first stage reaction of PTMG and MDI
The amounts of I and the viscosity modifier (acetone) were 5 kg and 1 respectively.
Molding was performed in the same manner as in Example 1 in accordance with the composition shown in Table 1, except that the amount was changed to 1.8 kg. The compositions of each composition and the results of the molding conditions are summarized in Tables 1, 2, and 3.

(Embodiment 3) The ejected material is received on a Teflon-coated belt moving at a speed of 20 m / min.
It is formed into a film having a uniform thickness with a blade. The procedure was the same as in Example 1 except that the adhesive was removed after the adhesion was removed. Tables 1, 2, and 3 collectively show the composition of each composition, mixing and molding conditions, and physical properties of the film.

Example 4 (1) Preparation of Composition (A) According to the composition shown in Table 1, the composition was prepared in the same manner as in Example 1. (2) Preparation of multifunctional terminal isocyanate prepolymer (composition (B)) 15.2 kg of PTMG (Mn = 1800) and 4.25
kg of MDI was put into a reactor equipped with a stirrer and reacted at 80 ° C. for 2.5 hours. Further, 0.06 kg of trimethylolpropane (TMP) was added, and 1.5
The reaction was allowed to proceed for a period of time, followed by the addition of 8.39 kg of a viscosity modifier (acetone). (3) Mixing and molding The same method as in Example 1 was followed. Tables 1 and 2 show the composition of each composition, mixing, molding conditions, and physical properties of the filaments.
3 collectively.

(Examples 5 to 8) Compositions (A) were prepared at the molar ratios shown in Table 1. On the other hand, a terminal isocyanate prepolymer was prepared under the conditions shown in Table 2, and after mixing both, the same treatment as in Example 1 was performed to obtain a molded article. The content of the imidazolidine compound shown in Table 1 was determined in the same manner as in Example 1. However, the polyester diol used in Example 8 had a Mn of 2,000 obtained from adipic acid and ethylene glycol / propylene glycol (7: 3, molar ratio). Tables 1, 2, and 3 show the composition of the composition, mixing, molding, and physical properties of the filaments in each example.

Example 9 (1) Preparation of Composition (A) According to the composition shown in Table 1, the composition was prepared in the same manner as in Example 1. However, in the case of this example, the composition was added with 20% by weight of a viscosity modifier (PTMG having both ends blocked with phenyl isocyanate) to increase the viscosity. (2) Preparation of terminal isocyanate prepolymer (composition (B)) Example 1 was followed except that the two-stage addition of MDI (0.88 kg) and the addition of a viscosity modifier (acetone) (10 kg) were not performed. In this case, the amount of isocyanate groups in the terminal prepolymer was 0.71 mol / kg. (3) Mixing and molding The same method as in Example 1 was followed. Tables 1 and 2 show the composition of each composition, mixing, molding conditions, and physical properties of the filaments.
3 collectively.

Example 10 (1) Preparation of Composition (A) The reaction composition having the composition shown in Table 1 was prepared. (2) Preparation of terminal isocyanate prepolymer (composition (B)) Adipic acid and ethylene glycol / glycerin (8:
15.2 kg of polyester triol (Mn = 1800) and 3.17 kg of MDI
Was placed in a reactor equipped with a stirrer and reacted at 80 ° C. for 3 hours under a nitrogen atmosphere. (3) Mixing and Forming Filaments were formed by mixing in the same manner as in Example 1.
Tables 1 and 2 show the composition, mixing molding conditions, and physical properties of the molded body.
3 is shown.

(Example 11) With the compositions shown in Tables 1 and 2,
Compositions (A) and (B) were prepared in the same manner as in Example 1 (provided that polydimethylsiloxane diol was used as the diol component).
The filament was obtained through annealing. Tables 1, 2, and 3 show the composition, mixing molding conditions, and physical properties of the molded body.

(Comparative Example 1) A filament was prepared according to the method described in JP-A-63-154719. As the composition (A) obtained from the diamine compound / carbonyl compound, ethylenediamine / acetone = 1
/1.5 (molar ratio) at 50 ° C. for 10 hours was used. The imidazolidine content of this composition is ¹ H-
The result of NMR measurement was 28 mol% (vs. M _DA ).
Further, there was no compound in which only one of ethylenediamine was a ketoimine group. The terminal isocyanate prepolymer used was the same as in Example 1 herein, and the preparation and addition amount of the oligomer diol used to bring the viscosity of the reaction composition close to that of the terminal isocyanate prepolymer depended on the raw materials. Mn of a PTMG is 1
Other than 800, the method described in the publication was followed. Tables 1, 2, and 3 show the preparation conditions, molding conditions, and results of the composition.

[0074]

[Table 1]

[0075]

[Table 2]

[0076]

[Table 3]

[0077]

As described above, according to the present invention,
By molding at the same time as the polymerization reaction, fluctuations in physical properties were remarkably improved, and a segmented polyurethane urea molded article excellent in unprecedented balance of physical properties between breaking strength, breaking elongation and stress was obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one example of a method for producing a polyurethane urea molded article of the present invention.

FIG. 2 shows a viscoelastic distribution state of a cross section of the SPU filament obtained in Example 1 observed by a viscoelastic mode of a scanning probe microscope.

FIG. 3 shows a viscoelastic distribution state of a cross section of an SPU filament obtained by a dry spinning method from an SPU solution prepared by a solution polymerization method as a control.

Claims (6)

[Claims] 1. A segment (1) comprising a reaction product of a bifunctional or higher-functional isocyanate compound and a polyol compound having a number average molecular weight of 800 to 6000, and a reaction product of the isocyanate compound and a diamine compound. The segment (2) has a purity of 80 mol% or more and 15 to 50 m.
A segmented polyurethane urea molded product having a branch density of mol / kg, and a single crystal having a spring constant of 0.1 to 1 N / m in a viscoelastic mode of a scanning probe microscope in an arbitrary surface or cross section of the molded product. When measured with a silicon cantilever (length: 125 μm, frequency: 7 to 8 kHz, horizontal resolution: 0.2 to 1 nm), 9 (μm) ² per 10 μm of island domains having a relatively high elastic modulus in the total area
A segmented polyurethane urea molded article having high strength and high elongation characterized by having a morphological structure distributed at a rate of ８０80%. 2. The segmented polyurethane urea molded article according to claim 1, wherein the molded article is a film. 3. The segmented polyurethane urea molded article according to claim 1, wherein the molded article is a fiber. 4. A method for producing a segmented polyurethane urea molded article having a high modulus by a method comprising the following steps: (1) a diamine compound represented by the following general formula [1] and a general formula [2]: At least one compound selected from the group consisting of a ketone compound and an aldehyde compound represented by the following general formula [3]:
The imidazolidine compound represented by the following formula and water were added to the diamine compound in a molar amount (M _DA ) of 40, respectively.
Preparing a composition (A) containing at least 30 mol% and at least 30 to 2000 mol%, (2) a composition (A) having a viscosity of 10 to 2 at 25 ° C.
The isocyanate-terminated prepolymer composition (B) prepared at 000 Pa · s was prepared by mixing the molar amount of isocyanate groups of the composition (B) / the molar amount of the diamine in terms of amino groups (2 M
_DA ) in the presence of 0.001 to 10 mol% of an acid compound with respect to M _DA so that the ratio (R) of 1 <R ≦ 1.5 is obtained, and molded into a precursor molded article (I). (3) polymerizing the precursor molded article (I) in a heated atmosphere to obtain a precursor molded article (II); and (4) annealing the precursor molded article (II). Embedded image (Where R represents a group selected from aliphatic or alicyclic hydrocarbons having 1 to 10 carbon atoms). (However, R ₁ and R ₂ are selected from hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and may be different from each other, except when both are hydrogen. Further, R ₁ and R ₂ are linked to each other. Including those forming a cyclic group by the following formula). (However, R represents a group selected from an aliphatic or alicyclic hydrocarbon having 1 to 10 carbon atoms. R ₁ and R ₂ are selected from hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, and Although they may be different, they exclude the case where both are hydrogen, and also include those in which R ₁ and R ₂ are linked to form a cyclic group.) 5. The method according to claim 4, wherein the molded article is a film. 6. The method according to claim 4, wherein the steps of preparing the composition (A) and preparing the mixture are continuously combined, and subsequently forming the fibers continuously without interruption.