JPH10292037A - Polycarbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polycarbonate desirable as a material for polyurethanes, polyamide elastomers, etc., excellent in hydrolysis resistance, low-temperature characteristics, low-temperature resistance, flexiblity and mechanical properties or a material for coating materials, etc., by transesterifying a polyol component with a carbonate compound and polycondensing the product of transesterification. SOLUTION: This polycarbonate comprises repeating units of formula I. Diol unit A constituting the repeating unit comprises diol residues of formulas II and III, and the molar ratio of diol residues II/diol residues of formula III is in the range of 5/95 to 45/55. It is desirable that the polycarbonate has a molecular weight of 300-30,000 and is terminated with hydroxyl. Formula II is a diol residue derived from 1,6-hexanediol, formula III is a diol residue derived from neopentyl glycol, and the manner of polymerization of the diol and the glycol may be random copolymerization or block copolymerization.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel polycarbonate, and more particularly to polyurethane, polyamide elastomer and polyester elastomer having excellent hydrolysis resistance, low temperature properties, cold resistance, flexibility and mechanical properties. The present invention relates to a novel polycarbonate having suitable characteristics as a raw material for forming a resin, and a constituent material such as a paint and an adhesive.

[0002]

2. Description of the Related Art As a conventional raw material for producing polyurethane, a combination of a polyol such as a polyester polyol or a polyether polyol and a polyisocyanate is generally used, and if necessary, a low molecular weight compound having an active hydrogen. Polyurethanes have been produced by adding and reacting compounds.

However, polyurethanes using a polyester polyol as a polyether component are relatively inadequate in resistance to hydrolysis, so that the surface of the molded product becomes tacky or cracks on the surface of the molded product in a relatively short time. There is a disadvantage that the use conditions are considerably limited.

Polyurethanes using a polyether polyol instead of a polyester polyol as the polyether component have improved hydrolysis resistance, but are extremely poor in oxidation-deterioration resistance,
There is a problem that properties such as abrasion resistance, oil resistance and solvent resistance are also inferior.

[0005] Further, as a polyurethane which has solved the above problems, a polycarbonate polyol having excellent hydrolysis resistance as a polyol component, specifically, 1,6 or 1
Polyurethanes using 1,6-hexanediol polycarbonate obtained by transesterification of -hexanediol and diphenyl carbonate are known, and this polyurethane has hydrolysis resistance, oxidation deterioration resistance, abrasion resistance, Although the oil resistance and the solvent resistance are improved, the solidification point is as high as about 46 ° C., so that they have a drawback that they are hard and have poor low-temperature characteristics and cold resistance.

[0006] That is, 1,6-
Polyurethane using hexanediol polycarbonate has a large tendency to crystallize, so that the soft segment component is liable to be crystallized and the elasticity thereof is likely to be impaired.

[0007] Therefore, it has been desired to realize a polyurethane-forming raw material, particularly polycarbonate, capable of giving a polyurethane excellent in flexibility, low-temperature characteristics and cold resistance while maintaining excellent properties such as hydrolysis resistance. I was

[0008]

SUMMARY OF THE INVENTION The present invention has been achieved as a result of studying to solve the problems in the prior art described above.

Accordingly, an object of the present invention is to provide a raw material for forming polyurethane, polyamide elastomer and polyester elastomer having excellent hydrolysis resistance, low temperature properties, cold resistance, flexibility and mechanical properties, as well as paints, adhesives and the like. An object of the present invention is to provide a novel polycarbonate having suitable properties as a constituent material such as an agent.

[0010]

In order to achieve the above object, the polycarbonate of the present invention has the following general formula (I)
Wherein the diol unit A constituting the repeating unit comprises diol residues represented by the following general formulas (II) and (III), and the diol residue (III) / ( II) molar ratio of 5
/ 95 to 45/55.

[0011]

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Embedded image The polycarbonate of the present invention has a molecular weight of 300 to 300.
Being in the range of 3,000, having a hydroxyl group at the molecular end, being used as a raw material for polyurethane, being used as a raw material for polyamide elastomer, being used as a raw material for polyester elastomer, being used as a constituent material of paint It is a condition that is desirably used as a constituent material of the adhesive and the adhesive, and when these conditions are satisfied, a special effect corresponding to each condition can be expected.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The polycarbonate of the present invention is produced by using a mixture of 1,6-hexanediol and neopentyl glycol as a polyol component and subjecting the polyol component and a carbonate compound to a transesterification reaction and polycondensation. And comprising a repeating unit represented by the above general formula (I).

Here, among the diol units A in the general formula (I), the general formula (II) represents a diol residue derived from 1,6-hexanediol, and the general formula (III) represents a diol residue. It indicates a diol residue derived from neopentyl glycol. The polymerization form of a mixture of 1,6-hexanediol and neopentyl glycol may be any of random copolymerization and block copolymerization. .

The diol residue (III) / (I
The molar ratio of I) is 5/95 to 45/55, especially 10/95.
It is preferably in the range of 90 to 30/70, and within this range, the low-temperature properties and flexibility of the polycarbonate itself are excellent, and the hydrolysis resistance and mechanical strength can be suitably secured. However, if it is out of the above range, one or both of the low-temperature property and the flexibility are impaired, which is not preferable.

The polyol component may be, for example, 1,5 other than 1,6-hexanediol and neopentyl glycol as long as the object of the present invention is not impaired.
-Pentanediol, caprolactonediol, 1,7
-Heptanediol, 1,8-octanediol, 2-
Ethyl-1,6-hexanediol, 2-methyl-1,
3-propanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, diethylene glycol, triethylene glycol, 2-methyl-1,8
Other polyol components such as -octanediol and 1,9-nonanediol can be included.

As the carbonate compound, aromatic carbonate compounds and aliphatic carbonate compounds can be used without particular limitation. Among them, diphenyl carbonate, diethyl carbonate,
Preference is given to using ethylene carbonate and propylene carbonate.

The method for producing the polycarbonate of the present invention is not particularly limited, and known methods can be applied.
For example, for n moles of a carbonate compound, (n + 1)
A typical example is a method of adding a mole of a polyol compound mixture, subjecting it to a transesterification reaction and polycondensation in the presence of heat and a catalyst, and continuously removing the alcohol generated under reflux conditions.

In this case, it is also desirable to add phosgene or chloroformate for the reaction.

Although a wide range of polycondensation catalysts can be used, preferred ones include titanium such as tetramethoxytitanium, tetraethoxytitanium, tetra-n-propoxytitanium, tetraisopropoxytitanium and tetrabutoxytitanium. Compounds, tin compounds such as di-n-butyltin oxide, di-n-butyltin dilaurate, dibutyltin diacetate, and magnesium;
Combinations of acetate such as calcium and zinc with antimony oxide or the above-mentioned titanium compound can be given.

The amount of these catalysts used is preferably in the range of 5 to 500 ppm based on the total polycarbonate produced. In addition, when polycarbonate is polycondensed using diphenyl carbonate, the use of a catalyst can be omitted.

According to such a production method, a polycarbonate having a desired molecular weight can be produced. And the molecular weight of polycarbonate is 300-3000.
It is desirable to be in the range of 0, especially 600 to 20,000, but of course, an appropriate molecular weight should be set according to the use of the obtained polycarbonate. However, if the molecular weight is less than 300, cold resistance and low-temperature properties become poor,
If it exceeds 30,000, the mechanical properties tend to decrease, which is not preferable.

Further, in consideration of using the obtained polycarbonate as a raw material for polyurethane, it is preferable that the molecular terminal is a hydroxyl group. The number of hydroxyl groups present in the polycarbonate depends on the use of the polycarbonate and cannot be unconditionally determined.
More than two pieces, especially those in the range of two to three pieces, are suitable because they can be applied to most uses.

The polycarbonate of the present invention can be applied to raw materials such as polyurethane, polyamide elastomer and polyester elastomer, constituent materials of paints and adhesives and various other uses. Because of its excellent performance of excellent low temperature properties, cold resistance, flexibility, and mechanical properties, it can be expected to be used as a new high-performance material.

[0024]

EXAMPLES The structure and effects of the present invention will be further described with reference to examples, but the present invention is not limited to these examples.

Example 1 A 2 liter round bottom flask equipped with a stirrer, a thermometer and a ten-stage plate distillation column was charged with 903 g of dimethyl carbonate, 509 g of 1,6-hexanediol, and 62.4 g of neopentyl glycol. , And 0.1 g of tetrabutyl titanate as a catalyst were charged, and the reaction was carried out under normal pressure under boiling conditions of dimethyl carbonate, and methanol distilled off was distilled off. After the reaction was continued until the distillation of methanol was completed, excess dimethyl carbonate was distilled off under a reduced pressure of 30 mmHg to obtain a reaction product.

514 g of the reaction product obtained above, 1,6-
127.4 g of hexanediol was placed in a 1 liter round bottom flask equipped with a stirrer, a thermometer and a distilling tube.
The reaction was carried out at 00 ° C. In this case, a large amount of methanol was distilled off at the beginning of the reaction. When the distillation of methanol was almost completed, the reaction was terminated by further distilling off methanol under reduced pressure of 10 mmHg.

The obtained polycarbonate had a molecular weight of about 10,000, a hydroxyl value of 57, and a hue (APHA) of 80.
Met. Proton NMR was measured in a heavy chloroform solvent using hexamethyldicyclohexane as a control compound. The hydrogen of the methyl group of neopentyl glycol was 0.9 ppm, which was adjacent to the oxygen atom of neopentyl glycol and 1,6-hexanediol. A resonance peak was shown at 4.1 ppm of hydrogen of the methylene group, and the molar ratio of neopentyl glycol residue / 1,6-hexanediol residue was calculated from these integrated values to be 7/93.

The polyurethane obtained by using this polycarbonate as a polyol component and reacting with a polyisocyanate has excellent balance of hydrolysis resistance, low-temperature properties, cold resistance, flexibility and mechanical properties. there were.

Example 2 954 g of dimethyl carbonate, 343 g of 1,6-hexanediol and 202 g of neopentyl glycol were placed in a 2 liter round bottom flask equipped with a stirrer, a thermometer and a ten-stage plate distillation column. The reaction was carried out at 190 ° C., and methanol distilled off was distilled off. The temperature was gradually raised from 210 ° C to 220 ° C.
Under a reduced pressure of 0 mmHg, methanol was further distilled at a temperature of 210 to 220 ° C. to terminate the reaction.

The obtained polycarbonate had a molecular weight of about 12,000, a hydroxyl value of 56, and a hue (APHA) of 60.
Met. Proton NMR was measured in a heavy chloroform solvent using hexamethyldicyclohexane as a control compound. The hydrogen of the methyl group of neopentyl glycol was 0.9 ppm, which was adjacent to the oxygen atom of neopentyl glycol and 1,6-hexanediol. A resonance peak was shown at 4.1 ppm of hydrogen of the methylene group, and the molar ratio of neopentyl glycol residue / 1,6-hexanediol residue was calculated from these integrated values to be 33/67.

The polyurethane obtained by using this polycarbonate as a polyol component and reacting with a polyisocyanate has excellent balance of hydrolysis resistance, low-temperature properties, cold resistance, flexibility and mechanical properties. there were.

[0032]

The polycarbonate of the present invention can be applied to raw materials such as polyurethane, polyamide elastomer and polyester elastomer, constituent materials of paints and adhesives, and various other uses. Because of its excellent performance of excellent properties, low temperature properties, cold resistance, flexibility, and mechanical properties, it can be expected to be used as a new high-performance material.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 169/00 C09D 169/00 C09J 169/00 C09J 169/00

Claims (8)

[Claims] 1. A polycarbonate comprising a repeating unit represented by the following general formula (I), wherein a diol unit A constituting the repeating unit is formed from a diol residue represented by the following general formulas (II) and (III): And the molar ratio of the diol residue (III) / (II) is 5/95 to 45/5.
5. Polycarbonate characterized by being in the range of 5. Embedded image Embedded image Embedded image 2. The polycarbonate according to claim 1, wherein the molecular weight is in the range of 300 to 30,000. 3. The polycarbonate according to claim 1, wherein the molecular terminal is a hydroxyl group. 4. The polycarbonate according to claim 1, which is used as a polyurethane raw material. 5. The polycarbonate according to claim 1, which is used as a raw material of a polyamide elastomer. 6. The method according to claim 1, which is used as a raw material for a polyester elastomer.
Polycarbonate according to item. 7. The polycarbonate according to claim 1, which is used as a constituent material of a paint. 8. The polycarbonate according to claim 1, which is used as a constituent material of an adhesive.