JPH02311561A - Polyurethane composition - Google Patents

Abstract

PURPOSE:To prepare a polyurethane compsn. excellent in the hydrophilicity and elasticity and useful for producing a molded article used in applications such as clothing, medical treatment, and cosmetics by dissolving chitin in a polyurethane soln. CONSTITUTION:Chitin pref. having a mol.wt. of 10,000 to 1,000,000 is dissolved in a polyurethane soln. (e.g. a soln. of a polyurethane obtd. by reacting ethylene diisocyanate with polyoxypropylene glycol in dimethylformamide).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to polyurethane compositions containing chitin, particularly as various molded articles.

The present invention relates to polyurethane compositions that can be used in a wide range of fields such as clothing, medicine, cosmetics, agriculture, and food.

(Prior art) Polyurethane is a highly elastic and excellent structural material, so
It is widely used as molded objects such as films, sponges, and fibers. On the other hand, chitin is used in the medical field in the form of fibers, films, etc. due to its biocompatibility.

For example, JP-A-60-215855 describes a nonwoven fabric made of chitin.

Further, JP-A-61-108631 describes films made of chitin, and these molded products have excellent hydrophilicity and good biocompatibility.

As a mixture of chitin and polyurethane, JP-A-63-301273 describes a mixture of chitosan or quaternized chitosan and water-dispersed urethane.
The purpose of this is to prevent shellfish and algae from adhering to underwater structures such as fishing nets and ship bottoms by coating them with this mixture. and.

This mixture is simply a mixture of granular urethane and chitin, and the physical properties of the resulting mixture do not retain those of the original urethane.

(Problems to be Solved by the Invention) Conventional polyurethanes have poor hydrophilicity and are difficult to use in fields that require affinity with water. Furthermore, nonwoven fabrics and films made of chitin do not necessarily have sufficient mechanical properties such as 9 strength, and have the disadvantage of being easily destroyed when subjected to strong external force.

As mentioned above, there is no composition that can be used in fields that require affinity with water and that can provide excellent mechanical properties such as strength, and the emergence of such a composition is strongly desired. was.

An object of the present invention is to provide a polyurethane composition that has excellent hydrophilicity and good biocompatibility, and can yield a molded article with high elasticity.

(Means for Solving the Problems) As a result of intensive research to solve the above problems, the present inventor has discovered that molded products obtained from a composition obtained by mixing chitin and a polyurethane solution have the inherent properties of polyurethane. The present invention was achieved by discovering that it does not impair the properties and also has hydrophilic properties.

That is, the first invention of the present invention is a polyurethane composition characterized by containing chitin in a polyurethane solution, and the second invention is a polyurethane composition characterized by containing chitin in a polyurethane solution. The gist of this invention is a polyurethane composition characterized by containing chitin.

The present invention will be explained in detail below.

The polyurethane compositions of the first invention and the second invention have chitin uniformly mixed in polyurethane.

In general, chitin is the residue of the exoskeleton of crustaceans, insects, etc. treated with hydrochloric acid and hydrochloric acid to remove ash and protein. Although J-(N-acetylglucosamine)1, chitin used in the polyurethane composition of the present invention also includes deacetylated products of various degrees in which aminoacetyl groups are deacetylated9, such as chitosan, Furthermore, -DH group of glycoside residue, -CH,01
Also included are chitin derivatives in which one group or -N82 group is esterified, etherified, carboxymethylated, hydroxyethylated, or low-ethylated.

The molecular weight of chitin used in the present invention is as follows.

Although not particularly limited, preferably 1 to 100
10,000, more preferably 50,000 to 300,000.

Further, the degree of deacetylation of chitin used in the present invention is not particularly limited, but is preferably 0 to 6.
0%, more preferably 0 to 40%. Deacetylation of chitin can be carried out by the well-known method of treating chitin with an alkali, and at this time, the alkali concentration used.

By appropriately changing the treatment temperature, treatment time, etc., the degree of deacetylation can be easily adjusted.

Polyurethane refers to one having a urethane bond -NHCOO- in the repeating unit of the main chain.9 In the present invention, polyurethane which is a polymer adduct of diisocyanate and glycol is particularly preferably used. The diisocyanate mentioned here has the general formula: 0CN-R, -NCO
[R, is (CH2) n (n=1-12).

There is something to be expressed. Also, as a glycol.

General formula: HOR20HCH2 is (CH2)-
(n=1~12), -(CH,), 0(CI(2
)2-, -C)12cmiCCH,-.

-cH2CH=CHCH2-, =(D-, etc.).

Alternatively, polyoxypropylene glycol, polyoxyethylene glycol, and copolymers of propylene oxide and ethylene oxide may be mentioned.

The first invention is a polyurethane composition characterized by containing chitin in a polyurethane solution.

The polyurethane solution referred to herein is a polyurethane solution in which the above-mentioned polyurethane is dissolved in a solvent. The polyurethane solvent used here.

Dimethylformamide, dimethylsulfamide.

Dimethylacetamide, N-methylpyrrolidone.

There are phenols, etc. The concentration of the polyurethane solution is preferably 0.1 to 15% by weight, more preferably 0.5 to 10% by weight.

Furthermore, chitin as used herein includes both solid and liquid chitin described above. Namely.

Examples of solid chitin include chitin powder. Furthermore, examples of liquid chitin include a chitin solution obtained by dissolving chitin in a solvent. As a solvent for chitin used here.

In the case of chitin, which has a relatively low degree of deacetylation.

Examples include dimethylacetamide or a mixture of N-methylpyrrolidone and lithium chloride, and a mixture of dichloroacetic acid or trichloroacetic acid and a chlorinated hydrocarbon. In the case of chitin with a relatively high degree of deacetylation (e.g., chitosan), Examples include aqueous solutions of acetic acid. As for the concentration of such chitin solution.

It is preferably 0.2 to 15% by weight, more preferably 0.5 to 10% by weight.

The solid content concentration in the polyurethane composition of the first invention is
Preferably 1 to 30% by weight, more preferably 2 to 20% by weight, most preferably 5 to 15% by weight.
It is. If it is outside the above range, it is not preferable because good performance cannot be obtained.

Further, the chitin content in the solid content of the polyurethane composition of the first invention varies depending on the purpose of use, etc.
．． It is preferably 5 to 80% by weight.

More preferably 5 to 70% by weight, most preferably
It is 10 to 60% by weight. If the content of chitin in the solid content of the polyurethane composition is less than the above range, the hydrophilicity will be insufficient, which is undesirable, and if it is larger than the above range, the mechanical strength will be weakened, which is undesirable.

In the first invention, the method for incorporating chitin into the polyurethane solution is not particularly limited, and the chitin powder or solution described above may be added to the polyurethane solution and mixed uniformly. Specifically, 1. For example, in order to incorporate chitin powder into the polyurethane solution described above, add chitin powder to the polyurethane solution in an amount of 0.5
-80% by weight is sufficient. In addition, in order to incorporate the chitin solution described above into the polyurethane solution described above, polyurethane solution: chitin solution = 0.5:9.5 to 9.5:0
．． 5 (weight ratio) is preferable.

In this way, the polyurethane composition of the first invention can be obtained.

Furthermore, from the composition of the invention thus obtained.

Various molded products can be molded. for that purpose,
A coagulating liquid common to the resulting solution 1, for example water.

A wet molding method in which a coagulating liquid such as methanol or ethanol is added and coagulated may be performed. In this way, fibers, fibrils, films, sponges.

A hydrophilic polyurethane molded product in the shape of a sheet or the like can be manufactured. It is also possible to coat other textiles such as polyester, nylon, acrylic, etc. with the compositions of the present invention.

The second invention of the present invention is a polyurethane composition characterized by containing solid chitin in polyurethane that does not contain a solvent.

What is the solvent-free polyurethane mentioned here?

This is a polyurethane melt obtained by heating and melting the above-mentioned polyurethane itself.

Furthermore, solid chitin includes powdered chitin and the like.

The content of chitin in the polyurethane composition of the second invention varies depending on the purpose of use, etc., but is preferably 0.5 to 80% by weight, more preferably 5 to 70% by weight.
, most preferably 10 to 60% by weight. If the chitin content in the polyurethane composition is less than the above range, the hydrophilicity will be undesirably low, and if it is larger than the above range, the mechanical strength will be undesirably low.

In the second invention, the method for incorporating chitin into polyurethane that does not contain a solvent is not particularly limited, and the chitin described above may be added to the polyurethane melt described above and mixed uniformly.

Specifically, 9. For example, to incorporate chitin powder into the polyurethane melt described above, add chitin powder.

0.5-80% by weight based on polyurethane melt
Good pillar.

In this way, the polyurethane composition of the second invention can be obtained.

Furthermore, from the composition of the invention thus obtained.

Various molded products can be molded. for that purpose,
A method such as cooling the obtained composition may be performed. In this way, hydrophilic polyurethane molded articles in the shape of fibers, fibrils, films, sponges, sheets, etc. can be produced. It is also possible to coat other textiles such as polyester, nylon, acrylic, etc. with the compositions of the present invention.

(Example) Hereinafter, the present invention will be specifically explained with reference to Examples.

The physical properties of the various molded products obtained in the examples were measured as follows.

The strength and elongation were measured using Tensilon UPM-3 (manufactured by Toyo Baldwin), and the bending strength and bending modulus were measured using a precision universal material testing machine 2020 (manufactured by Intesco). The water content was determined by a linear equation by immersing the sample in water for 30 minutes, removing water from the surface layer, and measuring the weight.

Example 1. Comparative Example 1 Chitin powder (manufactured by Shin Nippon Chemical, molecular weight approximately 100,000) was dissolved at 6% by weight in a mixed solution of dimethylacetamide and lithium chloride, and filtered to obtain a transparent chitin dope. On the other hand, a polyurethane prepared by a polyaddition reaction of 20 parts by weight of ethylene diisocyanate and 100 parts by weight of polyoxypropylene glycol (molecular weight 2000) was dissolved in dimethylformamide to obtain a 10% by weight transparent solution. These chitin solutions and polyurethane solutions were mixed at 1:2 (weight ratio).
A polyurethane composition according to the first invention could be obtained by mixing the polyurethane compositions in the following ratio. Subsequently, this composition was spun in a spinning bath containing hydrazine hydrate.

Before winding, the fiber was cold-stretched approximately 5 times to produce a 210-denier 60-filament fiber.

For comparison, a 10% by weight solution was prepared by dissolving only polyurethane in dimethylformamide.

A fiber similar to that in Example 1 was produced under the same conditions as in Example 1 (Comparative Example 1).

Table 10 shows the results of measuring the physical properties of these fibers.

As is clear from Table 1, the fibers obtained from the composition of the present invention have a degree of insertion approximately equal to that of conventional polyurethane fibers, and also have a high water content not found in conventional polyurethane fibers. Understood. This was an epoch-making product that could be used as a material for clothing that comes into direct contact with the human skin.

Example 2. Comparative Example 2 Polyaddition reaction of 30 parts by weight of tolylene diisocyanate (a mixture of (2,4-)lylene diisocyanate and 2,6-)lylene diisocyanate) and 100 parts by weight of polyoxypropylene glycol (molecular weight 2000) A polyurethane solution was obtained by dissolving 10% by weight of the polyurethane prepared above in dimethylformamide. The chitin dope used in Example 1 and the polyurethane solution obtained here were mixed in 1:1 ratio.
The polyurethane composition of the first invention could be obtained by mixing at a ratio of 4 (weight ratio). Next, this composition.

After pouring into a mold with a thickness of 10 I [11], water was added to solidify it, causing foaming inside the sheet, and when it solidified sufficiently over time, a polyurethane-like sponge was completed.

On the other hand, only the polyurethane solution was poured into the same mold as above and coagulated with water to produce a polyurethane sponge (Comparative Example 2).

The physical properties of both sponges were measured and were as shown in Table 2.

As is clear from Table 2, Example 2 had strength and bending strength comparable to those of Comparative Example 2, and had sufficient elongation. Moreover, it had a high moisture content and was easily compatible with water. Therefore, even when used in cosmetic puffs, etc., it blended well with cosmetic liquids, was very easy to use, and had sufficient durability.

Example 3. Comparative Example 3 60 parts by weight of hexamethylene diisocyanate and 1.4-
Polyurethane was produced by polyaddition reaction with 40 parts by weight of butanediol. This polyurethane was melted at 190°C, and chitin powder (particle size: 100 mesh bath, molecular weight: about 100,000, degree of deacetylation: 8%) was mixed thereto to give a concentration of 6% by weight to form the polyurethane composition of the second invention. Obtained. Next, while cooling this composition, the inner diameter is 3 mm and the thickness is lI.
! A 1ffl tube was molded.

For comparison, a tube of the same size was produced using polyurethane without chitin powder added (Comparative Example 3).

An indwelling vascular catheter was made from these tubes and placed in the dog's vein. When the tube was pulled out after 6 hours and the thrombus generated inside and outside the tube was observed, it was found that Example 3
There was less thrombus formation in Comparative Example 3.
Occlusion was observed at the tip of the tube, and a large amount of thrombus was generated. This effect is thought to be due to the addition of chitin, which made the surface layer of the tube hydrophilic.

Example 4. Comparative Example 4 Polyurethane, which is a polyadduct of 30 parts by weight of methylene diisocyanate and 70 parts by weight of polymethylene glycol (molecular weight 3000), was dissolved in dimethylformamide at a concentration of 5% by weight. on the other hand.

A solution was prepared by dissolving 5% by weight of chitosan (molecular weight approximately 80,000), which is chitin with a degree of deacetylation of 85%, in a 3% by weight acetic acid aqueous solution. This chitin solution and polyurethane solution are 1=1
(weight ratio) to obtain a polyurethane composition of the first invention. Next, this composition was coated on a nylon fabric and dried by dry heat (80° C.), and the nylon fabric was coated with a uniform composite of polyurethane and chitin.

For comparison, a nylon fabric coated only with polyurethane without chitin was produced (Comparative Example 4).

When the two were compared, Example 4 had better flexibility than Comparative Example 4, easily adsorbed water, and had a texture similar to that of natural fibers.

(Effect of the invention) Various molded articles obtainable from the composition of the present invention.

Shows excellent elastic modulus and elongation unique to polyurethane.

In addition, it is highly hydrophilic due to its high water content. Therefore, the composition of the present invention is suitable for use in clothing.

It is very effective as a material for various molded products used in fields such as medicine and cosmetics.

Claims (2)

[Claims] (1) A polyurethane composition characterized by containing chitin in a polyurethane solution. (2) A polyurethane composition characterized by containing solid chitin in polyurethane that does not contain a solvent.